Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 00:13:03 -0700 From: phclark, phclark To: teres@aiko.com I may have to do up a spreadsheet on what everyone's projected first shot setup is going to be... Just so I have a frame of reference. My present first shot is massive plinth with separate motor pod, platter and arm board assembly, three discrete assemblies on a massive base. BTW, I have concrete floors, so I don't anticipate some of the isolation problems others may have. I don't follow Thom's reasoning here. Given a sufficiently massive armboard assembly and same with the platter, with both on the same plinth, how would The relationship between the arm and >the bearing would be compromised. ??? Am I missing something conceptually? At some level, it is impractical to damp *all* resonances, and considering that the arm itself has resonance problems to be addressed, how does the potential interaction of arm and bearing become more problematic? Puzzled in Phoenix, Peter C -----Original Message----- From: Thom Mackris To: teres@aiko.com Date: Wednesday, March 08, 2000 8:32 PM Subject: Re: [teres] Armboard >Hi Steve, > >A while back there was a question about the benefits of a completely >detached pod / armboard. At the time, I expressed concern that this might >be a problem because the separate pod would most likely resonate >differently from the turntable base. The relationship between the arm and >the bearing would be compromised. > >I think this reasoning is correct, and following this line of thought, I >*think* we'd want the basic structure of the armboard to be the same as that >of the base. Notice the word "think" in the prior sentence :-) My current >philosophy for chassis/arm board is rigid first, damp later. Jon L & Chris >B are also advocates of this approach, but then again, we may all be full of >it. > >Cheers, >Thom > > >----- Original Message ----- >From: steve brooks >To: >Sent: Wednesday, March 08, 2000 9:07 PM >Subject: [teres] Armboard > > >> >> Has anyone given thought to building an armboard out of one of the >hardwoods >> that have a reputation for good sound...is it Gabon Ebony? >> Steve Brooks > > >__________________________________________________ >Do You Yahoo!? >Talk to your friends online with Yahoo! Messenger. >http://im.yahoo.com > > Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 03:07:38 -0700 From: Steve Zettel, Steve Zettel To: teres@aiko.com on 3/8/00 20:33, Thom Mackris at thom_mackris@yahoo.com wrote: > Hi Steve, > > A while back there was a question about the benefits of a completely > detached pod / armboard. At the time, I expressed concern that this might > be a problem because the separate pod would most likely resonate > differently from the turntable base. The relationship between the arm and > the bearing would be compromised. > > I think this reasoning is correct, and following this line of thought, I > *think* we'd want the basic structure of the armboard to be the same as that > of the base. Notice the word "think" in the prior sentence :-) My current > philosophy for chassis/arm board is rigid first, damp later. Jon L & Chris > B are also advocates of this approach, but then again, we may all be full of > it. > > Cheers, > Thom > I know you were addressing this to Steve Brooks, but I too am of the stiff, rigid structure camp. I am thinking now of a sandwich of aluminum-MDF-aluminum, or ss-mdf-ss. The question now is to constrain damping or not. I have heard compelling arguments either way. As far as the armboards, I am considering building up to the necessary height with the same metal-MDF sandwich, through bolted to the chassis by means of socket-head cap screws (bolts). With the metal left natural in a brushed finish it will be the mondo-industrial look. I'd like to hear others' thoughts and arguments pro/con for the contrained damping or none. Without constrained damping, I assume the mass-coupling is accomplished by means of tiptoes to a slab of some more inert substance? Is this where the damped Corian or some such occurs, further coupled to a sandbox for instance? Last question (for now): The slab of "stuff" resting on the sand -- suggestions and reasoning for either having the whole underside resting on the sand, or for having only large conical tiptoes sunk partway into the sand. Sorry about hijacking the armboard thread; all of a sudden I am bubbling over with ideas. Steve Z Subject: RE: [teres] Motor Pod Date: Thu, 9 Mar 2000 09:16:12 -0700 From: Schei, Kenneth, Schei, Kenneth To: 'teres@aiko.com' The arguements presented below for a hard "ringing" chassis with constrained-layer damping sound impressive, but I'm not sure I buy it, and I won't be convinced unless I hear the results. Please don't be offended because these are only my opinions. Correct me if I'm misconstruing it, but the type of sound you describe sounds a lot like the classic "high-end" sound, with lots of alleged high-frequency extension, detail, imaging, etc. The problem I have with that type of sound is that I just don't hear it when I listen to live, unamplified music. That leads me to believe that those qualities are not "preserved" but are added. The fact that you like to see a short, sharp ringing on your scope rather than a lower amplitude (e.g. better damped), longer duration trace, reinforces that belief. We're definitely describing two ways to skin a cat, and the resultant sound will probably be different with the two, but I'll stick to my way until I can hear results that would convince me otherwise. Cheers, Ken Ken Schei, P.E. Project Engineer Antarctic Support Associates Email address: scheike@asa.org Phone: 303-643-0163 > -----Original Message----- > From: Ivan Anderson [SMTP:ivan@win.co.nz] > Sent: Wednesday, March 08, 2000 3:31 AM > To: teres@aiko.com > Subject: Re: [teres] Motor Pod > > > > A hard metallic chassis is perhaps the closest thing to > > perfect mechanical grounding - you're only left with damping > > it. OTOH, losses built into the chassis through the use of > > the materials you mentioned, excepting to a degree marble, > > while certainly "quieter", could loose information through > > the interruption of this coupling. This loss is not > > recoverable. Lossy chassis seem to blur the signal and > > loose the fine detail so prized by advocates of permalloy, > > triodes, and sensitive cones, IMHO. Perhaps this occurs by > > the minute internal bending of lossy materials - I'm > > certainly no official expert in the subject. > > This aggrees with my own experience, when I had a business designing > and fabricating high end supports, tables, and shelves. > > I found that in order to control vibration, a system must first accept > it... and therfore will ring 'alarmingly' until grounded in some way. > Any vibration presented to, but not found in the damping system, must > be reflected back into the turntable, where it interferes with the > information we wish to retreive, cancelling, adding to and smearing > it. > > The best supports and vibration control sytems IMO show a trace on a > scope, as presented by an accelerometer (following a short pink noise > pulse), which has a large amplitude and fast decay. The systems which > present as a low amplitude trace (also tend to have longer decay) > smear and veil the information retrieved. Such systems based on > Corrian or mdf etc. as the primary layer display this characteristic. > > I have found that a light and rigid primary layer coupled to a massive > secondary layer to provide good control, with minimal information > loss. > > The rigid layer needs to be able to vibrate in order to damp this > vibration, or pass it on to further dampening layers. I acheived this > in different ways, thin wall steel tube welded to heavy wall large > cross section steel, formica - pvc foam - granite slabs and so on. > > I am undecided how to construct my table, but I am leaning towards a > chassis made from say, 50 x 20 x 2mm rectangular steel or s/steel tube > welded on the flat, coupled to some massive platform. > > BTW I found in my experiments, that filling the tube with dampening > material negated, to varying degrees, the dissipation abilities of the > plain tube. > > ... > > I'll follow my own suggestion to go with the ultra rigid > > chassis only to ensure that I get all the stuff out of the > > groove that I can. From _there_, the task is clearly to > > damp this chassis to critical. But I fear that losing the > > sonic goods, so to speak, by excessively decoupling is to > > risk irretrievable loss of information. > > Yes, I think this to be a 'sound' approach. > > Ivan > Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 10:04:55 -0700 From: Thom Mackris, Thom Mackris To: teres@aiko.com Steve, Igor contends that by having the tiptoes sink into the sandbox, you are better coupling the base/subchassis to the sand and therefor sinking vibrations into it than if the base merely rested on the sand. By not having the tip toes sink all of the way down so that they come to rest on the base, you are not coupled to the base of the sandbox so there is still isolation from the base and the floor. Audible differences? Beats me ... Thom --- Steve Zettel wrote: [snip] > Last question (for now): The slab of "stuff" resting > on the sand -- > suggestions and reasoning for either having the > whole underside resting on > the sand, or for having only large conical tiptoes > sunk partway into the > sand. > Steve Z __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 10:53:08 -0700 From: Ron Welborne, Ron Welborne To: teres@aiko.com It seems to me that one would be defeating the purpose of tiptoes if the point was not making contact with the base. When tiptoes first hit the market, me and my buddies had numerous discussions as to how they really work, but then we were all Sparkies so we were unable to reach a concensus. Any of you MEs care to enlighten me as to the detailed mechanics of tiptoes? Ron (a mechanically challenge EE) Welborne Labs wlabs@ix.netcom.com ph: 303.470.6585 fax: 303.791.5783 website --------------- www.welbornelabs.com ----------------- ----- Original Message ----- From: Thom Mackris To: Sent: Thursday, March 09, 2000 9:03 AM Subject: Re: [teres] Armboard > Steve, > > Igor contends that by having the tiptoes sink into the > sandbox, you are better coupling the base/subchassis > to the sand and therefor sinking vibrations into it > than if the base merely rested on the sand. > > By not having the tip toes sink all of the way down so > that they come to rest on the base, you are not > coupled to the base of the sandbox so there is still > isolation from the base and the floor. > > Audible differences? Beats me ... > > Thom > > --- Steve Zettel wrote: > > [snip] > > > Last question (for now): The slab of "stuff" resting > > on the sand -- > > suggestions and reasoning for either having the > > whole underside resting on > > the sand, or for having only large conical tiptoes > > sunk partway into the > > sand. > > Steve Z > > __________________________________________________ > Do You Yahoo!? > Talk to your friends online with Yahoo! Messenger. > http://im.yahoo.com Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 11:33:28 -0700 From: Thom Mackris, Thom Mackris To: teres@aiko.com Ron, all ... My take is that I want both motor pod and armboard to spike to the *same* hard surface so that the relationship between motor and bearing is constant. Even if the sitting on or in sand approach is superior from a vibrational standpoint, I think that it is compromised from the perspective of maintaining the motor/bearing relationship. I'm not sure if this means (a) spiking to a floating top plate or (b) spiking to the bottom of the sandbox, but this should be relatively easy to try. Cuurrently, I'm gravitating to option (a) Certainly if I'm using any kind of moving motor pod which many of us have been obsessing about, then submerging is not an option. How tip toes work? Ken? Gordon? Something about being mechanically analagous to a diode. I believe Igor's "point" was not so much about using tip toes as tip toes per se, but more one of getting the subchassis to settle into the sand more effectively. Cheers, Thom --- Ron Welborne wrote: > > It seems to me that one would be defeating the > purpose of tiptoes if the > point was not making contact with the base. > > When tiptoes first hit the market, me and my buddies > had numerous > discussions as to how they really work, but then we > were all Sparkies so we > were unable to reach a concensus. Any of you MEs > care to enlighten me as to > the detailed mechanics of tiptoes? > > > Ron (a mechanically challenge EE) > > Welborne Labs > wlabs@ix.netcom.com > ph: 303.470.6585 > fax: 303.791.5783 > website > www.welbornelabs.com __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 11:45:49 -0700 From: Jeremy Epstein, Jeremy Epstein To: teres@aiko.com Thom Mackris wrote: > I believe Igor's "point" was not so much about using > tip toes as tip toes per se, but more one of getting > the subchassis to settle into the sand more > effectively. Not to speak for Igor but as I remember his explanation, vibration is able to enter the sand more effectively (never to return) off the inserted exterior of the cone than off the flat planar bottom of the plate only. I think. -j -- ========================================= Jeremy Epstein .........jepstein@shwd.com ========================================= Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 11:54:50 -0700 From: Igor Kuznetsoff, Igor Kuznetsoff To: teres@aiko.com FWIW, Harmonix bases their voodoo on cherry, which they they won't admit unless pressed, but swear by after that. Igor --- steve brooks wrote: > > Has anyone given thought to building an armboard out > of one of the hardwoods > that have a reputation for good sound...is it Gabon > Ebony? > Steve Brooks > __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 12:00:50 -0700 From: Thom Mackris, Thom Mackris To: teres@aiko.com If that's true, and I suspect your are remembering this correctly Jeremy, then we are indeed using tiptoes as tiptoes (i.e. as a mechanical analog to a diode). Thom --- Jeremy Epstein wrote: > Thom Mackris wrote: > > > I believe Igor's "point" was not so much about > using > > tip toes as tip toes per se, but more one of > getting > > the subchassis to settle into the sand more > > effectively. > > Not to speak for Igor but as I remember his > explanation, vibration is > able to enter the sand more effectively (never to > return) off the > inserted exterior of the cone than off the flat > planar bottom of the > plate only. I think. > > -j > > -- > ========================================= > Jeremy Epstein .........jepstein@shwd.com > ========================================= > __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 13:03:06 -0700 From: Igor Kuznetsoff, Igor Kuznetsoff To: teres@aiko.com Folks, I don't believe that tiptoes are mechanical diodes. They are pointy, and *look* like they have a "directionality", but can pass vibration either way. What they do is concentrate force enormously at a very small area, the point, amplifying the intimacy of the contact, like as if a clamp was forcing the two things together. You've probably heard that a stylus exerts *tons* (IIRC) of force- generatated by only *grams* of downforce- at the (tiny) point of contact. The same amplification of pressure on a weight per square inch basis occurs with a cone or any pointed shape. A cone is mechanically stable & resistant/stiff to sub-modal vibration patterns, and is therefore particularly good at transmitting vibrations. It is a triangle from all lateral perspectives, after all. What a "tiptoe" shape really does best for us is to tightly couple whatever is *attached* to *it* (presumably firmly) to what it is standing on, without permanent means of attachment, or added mechanical clamping of any sort. This, then allows superior transmittal/grounding of vibration into whatever the rest is standing on. This does *not* guarantee that the vibration cannot return. That depends on what the supportive material does with it. The idea here would be that the noise should be "sunk", that is, *dissipated*/ made too diffuse to return to the cone with sufficient concentration to travel back with enough amplitude to do harm/ or even damped to death by superior mass/ internal damping characteristics. Regardless of what happens to the energy, the idea is to trap it *away* from where you want it not. When this works properly, the false impression made can suggest that the cone has acted as a "diode", because the noise is gone, seemingly one way, but the fact is that it was just trapped/dissipated in a harmless place, and sand is very good at doing just that. The reason for my suggesting coupling with cones, rather that laying a flat plate directly on sand is to take advantage of the tight coupling the cones give, having sunk into the sand until the constantly increasing area of support/contact (as the shape of the cone sinks into the sand) reaches supportive equilibrium. Laying a flat surface on sand will result in haphazard points of contact here and there with the sand, no matter how we try to bed the piece down. Additionally, the resulting height would be difficult to control/change incrementally, where the cones should be easy to reposition. Igor --- Thom Mackris wrote: > If that's true, and I suspect your are remembering > this correctly Jeremy, then we are indeed using > tiptoes as tiptoes (i.e. as a mechanical analog to a > diode). > > Thom > > --- Jeremy Epstein wrote: > > Thom Mackris wrote: > > > > > I believe Igor's "point" was not so much about > > using > > > tip toes as tip toes per se, but more one of > > getting > > > the subchassis to settle into the sand more > > > effectively. > > > > Not to speak for Igor but as I remember his > > explanation, vibration is > > able to enter the sand more effectively (never to > > return) off the > > inserted exterior of the cone than off the flat > > planar bottom of the > > plate only. I think. > > > > -j > > > > -- > > ========================================= > > Jeremy Epstein .........jepstein@shwd.com > > ========================================= > > > __________________________________________________ > Do You Yahoo!? > Talk to your friends online with Yahoo! Messenger. > http://im.yahoo.com > __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 13:31:35 -0700 From: Jeremy Epstein, Jeremy Epstein To: teres@aiko.com Igor Kuznetsoff wrote: > The reason for my suggesting coupling with cones, > rather that laying a flat plate directly on sand is to > take advantage of the tight coupling the cones give, > having sunk into the sand until the constantly > increasing area of support/contact (as the shape of > the cone sinks into the sand) reaches supportive > equilibrium. Laying a flat surface on sand will > result in haphazard points of contact here and there > with the sand, no matter how we try to bed the piece > down. Is any additional benfit gained by the shape of the cone as it radiates the vibration into the sand? In other words, does a flat plate radiate a planar wave into the sand and a cone radiate a 3-dimensional wave? As I pondered this, it occurred to me that perhaps a hemispherical foot would be even better than a cone with respect to the shape of the wave as it propagates into the sand. Inherent in this is an assumption that a more "scattered" wave pattern would be easier for the sand's internal friction to damp than a more coherent wave. -j -- ========================================= Jeremy Epstein .........jepstein@shwd.com ========================================= Subject: Re: [teres] Motor Pod Date: Thu, 9 Mar 2000 16:10:22 -0700 From: Steve Zettel, Steve Zettel To: teres@aiko.com on 3/9/00 08:16, Schei, Kenneth at SCHEIKE@asa.org wrote: > The arguements presented below for a hard "ringing" chassis with > constrained-layer damping sound impressive, but I'm not sure I buy it, and I > won't be convinced unless I hear the results. Please don't be offended > because these are only my opinions. Correct me if I'm misconstruing it, but > the type of sound you describe sounds a lot like the classic "high-end" > sound, with lots of alleged high-frequency extension, detail, imaging, etc. > The problem I have with that type of sound is that I just don't hear it when > I listen to live, unamplified music. That leads me to believe that those > qualities are not "preserved" but are added. The fact that you like to see > a short, sharp ringing on your scope rather than a lower amplitude (e.g. > better damped), longer duration trace, reinforces that belief. We're > definitely describing two ways to skin a cat, and the resultant sound will > probably be different with the two, but I'll stick to my way until I can > hear results that would convince me otherwise. > > Cheers, Ken > Yo, Thom! Any room for me on that "three sided fence" you're sitting on? Nice counterpoint to the stiff, rigid chassis argument, Ken. I can forsee that before this is all over, I may have two complete chassis of radically different audio philosophy to play with. . . Steve Z Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 16:37:31 -0700 From: Steve Zettel, Steve Zettel To: teres@aiko.com on 3/9/00 09:03, Thom Mackris at thom_mackris@yahoo.com wrote: > Steve, > > Igor contends that by having the tiptoes sink into the > sandbox, you are better coupling the base/subchassis > to the sand and therefor sinking vibrations into it > than if the base merely rested on the sand. > > By not having the tip toes sink all of the way down so > that they come to rest on the base, you are not > coupled to the base of the sandbox so there is still > isolation from the base and the floor. > > Audible differences? Beats me ... > > Thom Hmmm. The "easy to see" mechanism at work for the entire slab resting on the sand is the intimate damping contact with the lossy sand over the entire surface of the slab. Almost another "contrained" layer, if you will. It is not as clear to me how smaller "point contact" areas with the sand via cones accomplishes damping of the slab. However, it may be much more effective at providing isolation from vibrations trying to get from the stand, through the sandbox, to the turntable. . . If my understanding of the sandbox's function is to provide lossy isolation of the turntable from structure-borne vibrations, and some mass-loading of the system, if the sandbox is resting on innertubes then I guess I have answered my own question: rest the foundation slab (that the turntable and motor pod rest on) on cones, partway sunk into the sand. Address damping the slab in another manner. Thanks for letting me think out loud! Steve Z Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 17:36:31 -0700 From: Igor Kuznetsoff, Igor Kuznetsoff To: teres@aiko.com Don't know the answer to that one, it's a try-and-see, it might. Unfortunately, I suspect that it will be considerably harder to bed a hemisphere into the sand, or fine-position it. Finding suitable hemispherical feet is easy, I already have some that were intended as non-gouging temporary (as in 'til the position is tuned) feet for a speaker. Just go to the knobs & pulls section of any well stocked h'ware store, and look for the round knobs. They'll actually be about 3/4 of a full sphere & threaded with a common pitch, making them very easy to adapt. Just be sure to choose some solidly made metal ones, some are plastic. Igor --- Jeremy Epstein wrote: > Igor Kuznetsoff wrote: > > > The reason for my suggesting coupling with > cones, > > rather that laying a flat plate directly on sand > is to > > take advantage of the tight coupling the cones > give, > > having sunk into the sand until the constantly > > increasing area of support/contact (as the shape > of > > the cone sinks into the sand) reaches supportive > > equilibrium. Laying a flat surface on sand will > > result in haphazard points of contact here and > there > > with the sand, no matter how we try to bed the > piece > > down. > > Is any additional benfit gained by the shape of the > cone as it radiates > the vibration into the sand? In other words, does a > flat plate radiate a > planar wave into the sand and a cone radiate a > 3-dimensional wave? > > As I pondered this, it occurred to me that perhaps a > hemispherical foot > would be even better than a cone with respect to the > shape of the wave > as it propagates into the sand. Inherent in this is > an assumption that a > more "scattered" wave pattern would be easier for > the sand's internal > friction to damp than a more coherent wave. > > -j > -- > ========================================= > Jeremy Epstein .........jepstein@shwd.com > ========================================= > __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 18:50:12 -0700 From: Igor Kuznetsoff, Igor Kuznetsoff To: teres@aiko.com Thom, All, Actually, I expect the 'toes to do both. For starters, siting whatever is above them on the sand reliably & controllably. They also have to do a good job of transmitting vibration into the sand, in order to "sink" it. The sand(box) is meant to do more than one thing. From above, it is to provide a mass with good internal damping characteristics (especially if the recycled tire rubber chips I've been championing are mixed in to amplify this quality) in order to provide a place to dissipate whatever vibration we want to sink. From below, it is to provide a enough of a mass that any vibration traveling *up* the stand, and making it past whatever decoupling/isolation is applied (such as my long time favorite,the inner tube), cannot easily influence/move that mass, providing another barrier or filtration. To improve on that still further, I had suggested also lining the sandbox with a 1/2" or so of closed cell neoprene foam rubber (usually black, conveniently), and dividing the box into 2 sections-one for the main chassis, the other for the motor. This would create two decoupled sections, both good for sinking noise, but unable to link motor noise to the platter/arm. This last item would not be accomplished if there was only one section, or if the sections were bridged with a common plate. Of course, the two section idea is optional to this theme, but I really don't see why the motor & armboard need to be "spiked together". The sand will be plenty massive enough to stay put, and keep everything on it more than stable enough on a moment to moment basis, even if semiannual or so adjustment may be necessary. Between the arm & platter we obviously need a super stable link. But why would you want to go out your way to make a direct noise-transmitting connection between the motor pod and the arm? The benefit I *can* see to using such a plate would be in making easier (I expect) the initial alignment of the pulley with the platter, though in all the banter about the "geometric challenges" of pod systems, it was never mentioned that there is no exact position on the platter that the belt must use. We have a fair amount of latitude in that regard. Only the "azimuth", if you will, of the pulley is of importance, and that is really not all that much of a challenge. In the "drunk & crutch" system, one axis is easily adjusted simply by using the bubble level we talked about, and the other by adjusting the height of the 'toes relative to each other, or, in my case, anyway, just wiggle it into position on the sand (and isn't that simple enough - sounding, anyway - in practice this may prove to be less easy). With the mondo-mech linear bearing system, unless the vibration-sinking limited three screw system is used, the fine adjustments & mechanisms necessary to acomplish this will probably be more complex & difficult to realize. --- Thom Mackris wrote: > Ron, all ... > > My take is that I want both motor pod and armboard > to > spike to the *same* hard surface so that the > relationship between motor and bearing is constant. > > > Even if the sitting on or in sand approach is > superior > from a vibrational standpoint, I think that it is > compromised from the perspective of maintaining the > motor/bearing relationship. > > I'm not sure if this means (a) spiking to a floating > top plate or (b) spiking to the bottom of the > sandbox, > but this should be relatively easy to try. > Cuurrently, I'm gravitating to option (a) > > Certainly if I'm using any kind of moving motor pod > which many of us have been obsessing about, then > submerging is not an option. > > How tip toes work? Ken? Gordon? Something about > being mechanically analagous to a diode. > > I believe Igor's "point" was not so much about using > tip toes as tip toes per se, but more one of getting > the subchassis to settle into the sand more > effectively. > > Cheers, > Thom > > --- Ron Welborne wrote: > > > > It seems to me that one would be defeating the > > purpose of tiptoes if the > > point was not making contact with the base. > > > > When tiptoes first hit the market, me and my > buddies > > had numerous > > discussions as to how they really work, but then > we > > were all Sparkies so we > > were unable to reach a concensus. Any of you MEs > > care to enlighten me as to > > the detailed mechanics of tiptoes? > > > > > > Ron (a mechanically challenge EE) > > > > Welborne Labs > > wlabs@ix.netcom.com > > ph: 303.470.6585 > > fax: 303.791.5783 > > website > > www.welbornelabs.com > > __________________________________________________ > Do You Yahoo!? > Talk to your friends online with Yahoo! Messenger. > http://im.yahoo.com > __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 19:25:54 -0700 From: Thom Mackris, Thom Mackris To: Teres_List This is good stuff, Igor. It seems as if given the options we're considering for our motor mounting, we'll be using a top plate on the sandbox & experimenting with coupling this plate to the sand via tip toes (we know Ken will be using hockey pucks in place of tip toes - he's an Avalanche fan ). The base/subchassis can then be spiked to this plate. This will give us the flexibility to play with various motor configurations: drunk on crutches, inclined planes, linear bearings, whatever. Cheers, Thom ----- Original Message ----- From: Igor Kuznetsoff To: Sent: Thursday, March 09, 2000 12:01 PM Subject: Re: [teres] Armboard Folks, I don't believe that tiptoes are mechanical diodes. They are pointy, and *look* like they have a "directionality", but can pass vibration either way. What they do is concentrate force enormously at a very small area, the point, amplifying the intimacy of the contact, like as if a clamp was forcing the two things together. You've probably heard that a stylus exerts *tons* (IIRC) of force- generatated by only *grams* of downforce- at the (tiny) point of contact. The same amplification of pressure on a weight per square inch basis occurs with a cone or any pointed shape. A cone is mechanically stable & resistant/stiff to sub-modal vibration patterns, and is therefore particularly good at transmitting vibrations. It is a triangle from all lateral perspectives, after all. What a "tiptoe" shape really does best for us is to tightly couple whatever is *attached* to *it* (presumably firmly) to what it is standing on, without permanent means of attachment, or added mechanical clamping of any sort. This, then allows superior transmittal/grounding of vibration into whatever the rest is standing on. This does *not* guarantee that the vibration cannot return. That depends on what the supportive material does with it. The idea here would be that the noise should be "sunk", that is, *dissipated*/ made too diffuse to return to the cone with sufficient concentration to travel back with enough amplitude to do harm/ or even damped to death by superior mass/ internal damping characteristics. Regardless of what happens to the energy, the idea is to trap it *away* from where you want it not. When this works properly, the false impression made can suggest that the cone has acted as a "diode", because the noise is gone, seemingly one way, but the fact is that it was just trapped/dissipated in a harmless place, and sand is very good at doing just that. The reason for my suggesting coupling with cones, rather that laying a flat plate directly on sand is to take advantage of the tight coupling the cones give, having sunk into the sand until the constantly increasing area of support/contact (as the shape of the cone sinks into the sand) reaches supportive equilibrium. Laying a flat surface on sand will result in haphazard points of contact here and there with the sand, no matter how we try to bed the piece down. Additionally, the resulting height would be difficult to control/change incrementally, where the cones should be easy to reposition. Igor --- Thom Mackris wrote: > If that's true, and I suspect your are remembering > this correctly Jeremy, then we are indeed using > tiptoes as tiptoes (i.e. as a mechanical analog to a > diode). > > Thom > > --- Jeremy Epstein wrote: > > Thom Mackris wrote: > > > > > I believe Igor's "point" was not so much about > > using > > > tip toes as tip toes per se, but more one of > > getting > > > the subchassis to settle into the sand more > > > effectively. > > > > Not to speak for Igor but as I remember his > > explanation, vibration is > > able to enter the sand more effectively (never to > > return) off the > > inserted exterior of the cone than off the flat > > planar bottom of the > > plate only. I think. > > > > -j > > > > -- > > ========================================= > > Jeremy Epstein .........jepstein@shwd.com > > ========================================= > > > __________________________________________________ > Do You Yahoo!? > Talk to your friends online with Yahoo! Messenger. > http://im.yahoo.com > __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 19:26:08 -0700 From: Thom Mackris, Thom Mackris To: Teres_List Hi Peter, Treat my thoughts as partially educated guesses at best. You made one comment which is consistent with my reason for advocating an armboard being rigidly connected to the base/subchassis - that it's impossible to damp all resonances. My thinking (angels on the head of a pin again) is that a fixed armboard is more likely to maintain a fixed distance between arm and bearing. On a practical level, I'd hate to bump into the armboard and have to re-adjust my overhang. I realize that you'd probably spike the armboard block & there would be little dimples which would allow you to reposition it if you had a fit of clumsiness. OTOH, maybe you're onto something. Don't let me discourage you. Cheers, Thom ----- Original Message ----- From: phclark To: Sent: Wednesday, March 08, 2000 11:06 PM Subject: Re: [teres] Armboard > I may have to do up a spreadsheet on what everyone's projected first shot > setup is going to be... Just so I have a frame of reference. > > My present first shot is massive plinth with separate motor pod, platter and > arm board assembly, three discrete assemblies on a massive base. BTW, I > have concrete floors, so I don't anticipate some of the isolation problems > others may have. > > I don't follow Thom's reasoning here. Given a sufficiently massive armboard > assembly and same with the platter, with both on the same plinth, how would > > The relationship between the arm and > >the bearing would be compromised. ??? > > Am I missing something conceptually? At some level, it is impractical to > damp *all* resonances, and considering that the arm itself has resonance > problems to be addressed, how does the potential interaction of arm and > bearing become more problematic? > > Puzzled in Phoenix, > > Peter C > > > > -----Original Message----- > From: Thom Mackris > To: teres@aiko.com > Date: Wednesday, March 08, 2000 8:32 PM > Subject: Re: [teres] Armboard > > > >Hi Steve, > > > >A while back there was a question about the benefits of a completely > >detached pod / armboard. At the time, I expressed concern that this might > >be a problem because the separate pod would most likely resonate > >differently from the turntable base. The relationship between the arm and > >the bearing would be compromised. > > > >I think this reasoning is correct, and following this line of thought, I > >*think* we'd want the basic structure of the armboard to be the same as > that > >of the base. Notice the word "think" in the prior sentence :-) My > current > >philosophy for chassis/arm board is rigid first, damp later. Jon L & Chris > >B are also advocates of this approach, but then again, we may all be full > of > >it. > > > >Cheers, > >Thom > > > > > >----- Original Message ----- > >From: steve brooks > >To: > >Sent: Wednesday, March 08, 2000 9:07 PM > >Subject: [teres] Armboard > > > > > >> > >> Has anyone given thought to building an armboard out of one of the > >hardwoods > >> that have a reputation for good sound...is it Gabon Ebony? > >> Steve Brooks > > > > > >__________________________________________________ > >Do You Yahoo!? > >Talk to your friends online with Yahoo! Messenger. > >http://im.yahoo.com > > > > > __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: [teres] teres tt project Date: Thu, 9 Mar 2000 19:35:27 -0700 From: JERROLD GORSKI, JERROLD GORSKI To: teres@aiko.com Hi I'd like to make a suggestion regarding isolation, dampening and leveling. I have used four small mylar balloons under my sandbox with great success for about two years. These 4 inch diameter balloons have an inner tube's cut out air valve inserted in the neck of the balloon, glued inside and sealed outside with wire twists. each balloon is independently inflated with a air pump in order to precisely level the platter. I have had no problem with leakage at all. if you use an inner tube it will be dangerously unstable, rocking and rolling, but this is inherently stable. I even have a balloon underneath my stand alone motor inside the sandbox. I can adjust the level of the pulley, if needed. so the balloons support the weight of the sandbox and my VPI. The cost is negligible. It looks kind of cool. I use these balloons under everything else except my speakers. give it a try. regards Jerry I just found this site referenced in phonogram digest. Sorry, but I have not read the back archives if this is irrelevent. Subject: Re: [teres] Armboard Date: Thu, 9 Mar 2000 21:18:41 -0700 From: MaughanAudio@aol.com, MaughanAudio@aol.com To: teres@aiko.com Mechanical diodes? How cones work? Picture the cross sectional shape of flat surface being supported by a cone with the tip of the cone standing on top of another surface. Mechanical energy from the upper surface having contact with the large surface area of the cones base will more easily transfer at certain frequencies dependent on the coupling efficiency between the two surfaces. Likewise at the contact of the cones point and the base, another set of frequencies will be transfered again dependent on the coupling efficiency of that junction. The way I perceive it, the larger contact with the cones base will act as a comb filter (as any mechanical coupling will with one or more prominent resonant modes). The contact with the cones point will essentially do the same thing, however if all other variables are the same the prominent resonant modes will shift upward in frequency given the smaller contact point. Now let's try to view what is happening to this mechanical energy inside the cone by viewing the cross section and imagine that the cone is a reflecting pool of water. We are viewing this pool shaped as a cross-section of the cone. When vibrations are entering through the cones base, imagine that energy as ripples heading towards the point. Those ripples as they migrate towards the point also create reflected ripples from the angled sides that then travel inward and cross the center axis of the cone merging with the ripples from the opposite side. This merging reinforce and cancel ripples dependent on the phase arrival of the junctions. Meanwhile the original ripples are continuing towards the point and the sides are closing in, creating more reflections that merge sooner and sooner. Thus as more and more reflections occur more and more harmonics are being created and others nullified. By the time the original energy has reached the point of the cone, that energy has been transformed into many lower amplitude higher order harmonics. The reduced footprint of contact of the point allows for an efficient transmission of these higher order harmonics. Here is the caveat, since this transmission at the junction is acting as a comb filter, a portion of these harmonics will see a higher transmission impedance and reflect back. That is why cones always change the sound, not only do they couple and sink vibrational energy, they also transform that energy into higher order harmonics and also reflect some energy back into the system. The better sounding cones always have a channel or chamber of some sort filled with lossy material to help absorb some of these higher order harmonics. Transmission of energy is also occurring from the lower plane through the point of the cone towards the base of the cone and then into the plane that contacts the base of the cone. Transmission of energy in this direction is less noticeable since the harmonic nodes of the comb filter effect are shifted upward from what the signature of the junction at the larger contact of the cones base is. At least this is how I picture what is occurring. Subject: RE: [teres] Motor Pod Date: Fri, 10 Mar 2000 01:33:24 -0700 From: Igor Kuznetsoff, Igor Kuznetsoff To: teres@aiko.com >Unfortunately, I can't yet visualize how to solve the >three issues I think I see with the unsecured motor: >Belt chafing, Jon, There will be some type of belt chafing-let's call it "scrub" as in "scrub radius" from automotive applications- regardless of methods used or the perfection of alignment. It will either occur from the flat belt's going over a crowned surface, or a small misalignement of the pulley, or belt wander. Regardless of any desire to implement the philosophic perfection of machinistic protocols while observing reasonable convention to render "proper" design (and that is not a bad goal), engineering really is, on a very basic level, as in "reality intrudes", the intelligent balancing of tradeoffs. Let's be realistic about what's practical. Manfred doesn't even think this much is necessary. Gary's idea of putting something compliant under the pod negates the possibility of tight coupling to whatever the pod sits on, but allows some movement to make tension more controllable, and works. This is not too different from an early suggestion of mine where I stated that some compliance would be necessary, albeit only in that plane. The limiting factors in this and a no-compliance setup would be the lack of fine control & repeatability. > motor "roll" or shudder, This is indeed a legitimate concern, which I share. In my pod, I hope to control this with a combination of mass and damping. The pod will have, built into it a VHD (Viscous Harmonic Damper), as outlined in two other posts. I may even build the tensioning weight as a second (smaller) VHD, as that outboard position would be a very advantageous location to place such a device to control shudder in the motor/platter axis. Failure to control this adequately would be my most likely reason to adopt linear bearings as part of the solution. >and lack of mass coupling. Well, there my proposed system has no problems. Motor tightly coupled to the mounting plate, that tightly coupled to the pod body, and that tightly coupled via points to whatever all this sits on. This would be that unavoidable trade-off situation, should I need to adopt linear bearings, which would not couple as tightly, not to mention the pulley position adjusters, which would probably be even worse. Igor --- "Schei, Kenneth" wrote: > Jon: > > I admire your tireless quest for perfection, but > many of us think that > perfection is unobtainable. You say that you prefer > a perfectly aligned > pulley so there is no belt chafing, but how will you > center your belt? I > respectfully dispute your contention that it will be > centered on a > flat-faced pulley, by perfection, without lateral > hunting. IMHO, there > needs to be a method of centering the belt; three > methods come to mind: > flanges, a convex-shaped pulley face, or a wide > enough pulley that allows > the belt to wander back and forth without going off > the edge (pun?). All > three add a modulation to the belt motion. Igor an > I accept that reality > and we are trying to think of the best ways to > mitigate it rather than try > to deny it. > > I also would like to question your use of SS and > granite. Both have been > addressed in prior posts as being undesirable for a > TT base because they > ring. Marble and Corian are much better than > granite if you want a > stone-like material. "Lowly" MDF is an excellent > material that can be > finished beautifully with veneer and solid wood > trim, with little more than > hand tools. I like the idea of cherry-veneered and > trimmed MDF alternating > with corian laminations for my base. And don't get > me started again on > Ennemoser's theories and C37! > > Cheers, Ken > > Ken Schei, P.E. > Project Engineer > Antarctic Support Associates > Email address: scheike@asa.org > Phone: 303-643-0163 > > > > -----Original Message----- > > From: Jon Lane [SMTP:jhlane@email.msn.com] > > Sent: Tuesday, March 07, 2000 7:33 AM > > To: teres@aiko.com > > Subject: RE: [teres] Motor Pod > > > > > I missed your recent thoughts on what to sled. > > > Indeed, we all seem to be in > > > agreement with respect to the benefits of > keeping > > > the motor firmly coupled > > > to the mass of the pod. I can very easily get > > > behind the concept of the > > > entire motor pod being on a sled. > > > > One of the philosophies I think we need to always > keep in > > mind is that of proper machine design - we're > making a > > precise machine here and while our intuitions on > lead, MDF, > > adhesives, levitating platters and tilting motors > and other > > interesting notions are very valid from the > perspective of > > their _intended effect_, thus far we have made a > true > > machine and have observed reasonable convention in > it's > > philosophy and execution. > > > > One example: Personally, I will use a pair of 1" > plates of > > pure 6061 alloy laminated together for the base of > my > > platter, not unlike a small machine table to which > things > > attach with high precision and intimate mechanical > bonding. > > This will be (at first) limited resonance-wise by > only a > > thin scrim of sorbothane-like material between it > and 2" of > > granite. From experience, these two constrained > layers will > > quiet the base sufficiently without compromising > mechanical > > coupling. The motor pod will also be a heavy > block of > > aluminum with motor bolted firmly in absolutely > vertical > > alignment. The pod's underside will be machined > flat > > relative the motor alignment and will be held > there by the > > surface of the granite, again, with an > intermediate thin > > damping layer. Sliding bearings are an available > option > > under consideration. > > > > Many can argue, and probably successfully, that > this isn't > > "tweak" enough. I'd counter that in fact it will > be insofar > > as it immediately lends itself to evolutionary > improvements > > in tuning. The design tuning only _begins_ at the > stage I > > describe here, as I intend it. However, there > simply will > > be no "non-workmanlike" portions to the design. > It will be > > utterly stable, perfectly aligned, and > bulletproof. Or at > > least I hope it will be ;o) I merely want to > observe proper > > machinist protocol and wish to avoid anything > resembling a > > spit and bailing wire philosophy - not that that's > what > > anyone else has proposed here, I hasten to add. > I'm just > > explaining that my personal philosophy is one of > ensuring > > that all components are fit together precisely and > all > > portions of the design are simple and effective. > > > > Unfortunately, I can't yet visualize how to solve > the three > > issues I think I see with the unsecured motor: > Belt > > chafing, motor "roll" or shudder, and lack of mass > coupling. > > > > While Manfred hasn't commented, I'm betting that > the motor > > won't be capable of driving much energy back into > the > > mountings, making the "open" design less > problematic. > > Anybody? But I'm still betting further, that > actually > > because of this, any vibration that IS present > will handily > > be removed entirely by mass coupling. Second, > while belt > > chafe isn't a serious issue, why court it at all? > Igor's > > insightful comments include a reference to FM > noise, and > > that's exactly, I think, what we should > intuitively be aware > > of. With a line contact pulley, the belt > perpetually being > > driven by, in effect, a constant series of minute > arcs > > across it's underside is, IMHO, something to > avoid. > > > > > Those of us are who are thinking about adding > > > belt tensioning force prefer > > > using gravity for obvious reasons of energy > > > (non)storage. I now wonder as > > > you do if a spring (rubber or metal) could > > > effectively supply the force. In > > > the "sled" approach, perhaps the mass of the pod > > > is high enough to filter > > > out any spring resonances. In Igor's approach, > I > > > think gravity would be > > > necessary (and way cool looking), since the > > > system depends directly on the > > > locating force for it's stability. > > > > I think it's clear that weighting the scope of > travel is > > theoretically the superior method, but once again, > I ask if > > it's necessary. That is, in the case of gently > separating a > > pair incredibly massive entities (relative to our > needs > > here) isn't it just as simple as dropping in a > couple of > > soft, large diameter springs between platter base > and motor > > block? Especially in light of what lengths some > are > > presumably going to damp both bases, two small > springs > === message truncated === __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: RE: [teres] Armboard Date: Fri, 10 Mar 2000 08:41:16 -0700 From: Schei, Kenneth, Schei, Kenneth To: 'teres@aiko.com' I'm sorry, but the concept of a mechanical diode requires that we repeal the law of physics that says every action has an equal and opposite reaction. I'm not prepared to do that yet. Cheers, Ken Ken Schei, P.E. Project Engineer Antarctic Support Associates Email address: scheike@asa.org Phone: 303-643-0163 > -----Original Message----- > From: Thom Mackris [SMTP:thom_mackris@yahoo.com] > Sent: Thursday, March 09, 2000 10:59 AM > To: teres@aiko.com > Subject: Re: [teres] Armboard > > If that's true, and I suspect your are remembering > this correctly Jeremy, then we are indeed using > tiptoes as tiptoes (i.e. as a mechanical analog to a > diode). > > Thom > > --- Jeremy Epstein wrote: > > Thom Mackris wrote: > > > > > I believe Igor's "point" was not so much about > > using > > > tip toes as tip toes per se, but more one of > > getting > > > the subchassis to settle into the sand more > > > effectively. > > > > Not to speak for Igor but as I remember his > > explanation, vibration is > > able to enter the sand more effectively (never to > > return) off the > > inserted exterior of the cone than off the flat > > planar bottom of the > > plate only. I think. > > > > -j > > > > -- > > ========================================= > > Jeremy Epstein .........jepstein@shwd.com > > ========================================= > > > __________________________________________________ > Do You Yahoo!? > Talk to your friends online with Yahoo! Messenger. > http://im.yahoo.com Subject: RE: [teres] Armboard Date: Fri, 10 Mar 2000 08:48:47 -0700 From: Schei, Kenneth, Schei, Kenneth To: 'teres@aiko.com' Igor: An excellent real-world analysis of how tip-toes can work by tightly coupling our component to a lossy sink. Ken Ken Schei, P.E. Project Engineer Antarctic Support Associates Email address: scheike@asa.org Phone: 303-643-0163 > -----Original Message----- > From: Igor Kuznetsoff [SMTP:gorkuz@yahoo.com] > Sent: Thursday, March 09, 2000 12:02 PM > To: teres@aiko.com > Subject: Re: [teres] Armboard > > Folks, I don't believe that tiptoes are mechanical > diodes. They are pointy, and *look* like they have a > "directionality", but can pass vibration either way. > What they do is concentrate force enormously at a very > small area, the point, amplifying the intimacy of the > contact, like as if a clamp was forcing the two things > together. You've probably heard that a stylus exerts > *tons* (IIRC) of force- generatated by only *grams* of > downforce- at the (tiny) point of contact. The same > amplification of pressure on a weight per square inch > basis occurs with a cone or any pointed shape. A cone > is mechanically stable & resistant/stiff to sub-modal > vibration patterns, and is therefore particularly good > at transmitting vibrations. It is a triangle from all > lateral perspectives, after all. What a "tiptoe" > shape > really does best for us is to tightly couple whatever > is *attached* to *it* (presumably firmly) to what it > is standing on, without permanent means of attachment, > or added mechanical clamping of any sort. This, then > allows superior transmittal/grounding of vibration > into > whatever the rest is standing on. This does *not* > guarantee that the vibration cannot return. That > depends on what the supportive material does with it. > The idea here would be that the noise should be > "sunk", that is, *dissipated*/ made too diffuse to > return to the cone with sufficient concentration to > travel back with enough amplitude to do harm/ or even > damped to death by superior mass/ internal damping > characteristics. Regardless of what happens to the > energy, the idea is to trap it *away* from where you > want it not. When this works properly, the false > impression made can suggest that the cone has acted as > a "diode", because the noise is gone, seemingly one > way, but the fact is that it was just > trapped/dissipated in a harmless place, and sand is > very good at doing just that. > The reason for my suggesting coupling with cones, > rather that laying a flat plate directly on sand is to > take advantage of the tight coupling the cones give, > having sunk into the sand until the constantly > increasing area of support/contact (as the shape of > the cone sinks into the sand) reaches supportive > equilibrium. Laying a flat surface on sand will > result in haphazard points of contact here and there > with the sand, no matter how we try to bed the piece > down. Additionally, the resulting height would be > difficult to control/change incrementally, where the > cones should be easy to reposition. > > Igor > > > --- Thom Mackris wrote: > > If that's true, and I suspect your are remembering > > this correctly Jeremy, then we are indeed using > > tiptoes as tiptoes (i.e. as a mechanical analog to a > > diode). > > > > Thom > > > > --- Jeremy Epstein wrote: > > > Thom Mackris wrote: > > > > > > > I believe Igor's "point" was not so much about > > > using > > > > tip toes as tip toes per se, but more one of > > > getting > > > > the subchassis to settle into the sand more > > > > effectively. > > > > > > Not to speak for Igor but as I remember his > > > explanation, vibration is > > > able to enter the sand more effectively (never to > > > return) off the > > > inserted exterior of the cone than off the flat > > > planar bottom of the > > > plate only. I think. > > > > > > -j > > > > > > -- > > > ========================================= > > > Jeremy Epstein .........jepstein@shwd.com > > > ========================================= > > > > > __________________________________________________ > > Do You Yahoo!? > > Talk to your friends online with Yahoo! Messenger. > > http://im.yahoo.com > > > __________________________________________________ > Do You Yahoo!? > Talk to your friends online with Yahoo! Messenger. > http://im.yahoo.com Subject: [teres] Sources for Mylar Party Baloons Date: Sun, 12 Mar 2000 22:29:21 -0700 From: Thom Mackris / Joan Panzella, Thom Mackris / Joan Panzella To: Teres_List; w.r.galbraith@worldnet.att.net All, Several folks were asking about Jerrold's mylar party baloon sources. Here's a copy of his e-mail (forwarded to the Joe List by Jeremy) regarding sourcing. Cheers, Thom ------------------------------- -----Original Message----- From: Jeremy Epstein [mailto:jepstein@shwd.com] Sent: Wednesday, January 26, 2000 7:01 AM To: gorfam@worldnet.att.net; Joenet Subject: Re: [JN] Re: Sources for Innertubes? and bladders? JERROLD GORSKI wrote: > I've already recieved requests for more info: > 1 800 285 4000 > 4 inch silver circles > 04SSOU > R140 > 25 in a pack > > I forget which glue I used, contact cement or silicone. obviously avoid > getting it into the valve. I used sandpaper to roughen and reduce the > valve diameter slightly as it is a tight fit in the neck of the balloon. > The hair curling iron cost about $6, 3/4 inch curls guys.apply the iron > about 5 minutes for a good seal. I got my used inner tubes at mineola bike > shop btw. > anyway enjoy...let me know how it goes and could you forward the ordering > info to the list. thanks. Consider it done, and thanks for following up. Do you think you will subscribe to JoeNet? Sounds like you have the right (cheapskate experimenter) spirit! -j -- ========================================= Jeremy Epstein .........jepstein@shwd.com ========================================= Subject: Re: [teres] isodamp Date: Mon, 13 Mar 2000 09:18:03 -0700 From: Stanley Goudge, Stanley Goudge To: teres@aiko.com; teres@aiko.com Alvin, The isodamp thing started with someone giving us the idea the platter needs to be damped, so I suggested the Well Tempered approach by using isodamp at the bottom of the platter. From there we figured it can and will be used in some subchassis and armboard designs. At this point its every man for himself in regards to this area. My plea for the use of SS in CLD has caused concerns in the lossy camp, however this was not my intensions, only to inject another idea, one that cannot be executed by table saw or router as is the case with most lossy designs. BTW most TT designers begin with a lossy design only to upgrade or redesign using more rigid materials, SS or aluminum seem to be materials of choice, not only for TT but tonearms as well. The lossy route is well travelled and I believe their are better routes which will lead us to much higher ground. Stan At 03:15 PM 3/12/2000 -0500, Alvin Richardson wrote: >Gents, >I am relatively new to the digest, and I try to keep up with what is going >on, although with too many different forums going on at once, it is >difficult to know what is being done. In this instance it would appear that >this purchase is being made apart from the general consensus. My question >is, how is this contributing to the making of the teres? I am assuming that >it is in reference to damping the subchassis. Am I correct? If it will >contribute to making my table that much better, I would hate to miss out. >The sizes/quantities being ordered, will this correspond to the finished >size of the subchassis? Thanks! al>> > >>From: Stanley Goudge >>Reply-To: teres@aiko.com >>To: teres@aiko.com >>Subject: [teres] isodamp >>Date: Fri, 10 Mar 2000 10:41:19 -0600 >> >>Heres the latest list for the isodamp order. Deadline is this Monday >>3-13 to get some. I'm too lazy or too busy (pick one) to fiqure exact >>shipping so I'll add $10 for packing each order + $1 per pound for UPS >>gound. >>The quoted prices did not include my shipping costs for receiving. I'll >>just include >>it in the $10. Personal checks ok. >> >> >>Jon Lane 16" square CN-12 single side peel and stick >>$11.50 + $1 x 1.6 lbs + $10 = $23.10 >> >>Paul Croft 3 X 1' x 1' tiles CN-38 single side peel and stick >>$37.58 + $1 x 8.1 lbs + $10 = $55.68 >> >>Scott Frazer 6 x 1' x1' tiles CN-12 single side peel and stick >>$33.84 + $1 x 5.5 lbs + $10 = $49.34 >> >>Maughan Audio 2 x 1' x 1' tiles CN-38 single side peel and stick >>$55.48 + $1 x 10.8 lbs + $10= $76.28 >> 2 x 1' x 1' tiles CN-38 double side peel and >>stick >> >> >> >>Stan Goudge >>1409 limestone ln. >>Cedar Park,TX 78613 >>512 250 0642 hm >>512 378 1505 wk >> > >______________________________________________________ >Get Your Private, Free Email at http://www.hotmail.com > Subject: RE: [teres] Motor Pod Date: Mon, 13 Mar 2000 10:59:23 -0700 From: Igor Kuznetsoff, Igor Kuznetsoff To: teres@aiko.com Stan, I echo Ken's thought that this is an interesting method, and one that I think can work. I do vaguely remember seeing torque reaction systems used somewhere to effect some control functions, but remember that their action is rather *rough*, probably because the highest torque exerted by electric motors is under startup or stall conditions. This seems sure to cause "hunting" problems, which could become difficult to solve & may add complexity to what starts out with some complexity already, that being one of my concerns with this plan. Finally, This would require the use of a bearing (maybe even more than one by the time stable function is realized), and this would compromise the tight coupling optimal to sinking motor noise. Still, this is an intriguing idea, and I would be curious to see how it works, should you choose to follow it up. Igor "Schei, Kenneth" wrote: > Stan: > > You propose a very interesting method. However, I > respectfully think that > using gravity via a counterweight or the weight of > the motor pod on an > eccentric support would be simpler and better. > Using gravity would assure > that there was no "hunting," because gravity is > constant and non-reacting > (at least on the Newtonian level). I don't envision > any problem with motor > axis misalignment because the amount of rotation to > maintain belt tension > would be mininal. > > Cheers, Ken > > Ken Schei, P.E. > Project Engineer > Antarctic Support Associates > Email address: scheike@asa.org > Phone: 303-643-0163 > > > -----Original Message----- > > From: Stanley Goudge [SMTP:sgoudge@cisco.com] > > Sent: Monday, March 06, 2000 7:33 PM > > To: teres@aiko.com; teres@aiko.com; teres@aiko.com > > Subject: RE: [teres] Motor Pod > > > > Sorry Guys, > > I just can't leave this thing alone. You'll > need paper & pencil to > > figure this one. Forget what I said below, > > after further thoughts it should be possible to > use the torque of the > > motor to tighten the belt automatically. > > All that is needed is a thust bearing to allow > the motor pod to rotate > > freely. > > Ok picture this, your looking down the left side > of the turntable with > > motor in the foregound and platter in the > background. > > Now the motor spins clockwise which creates a > counter-clockwise torque on > > the pod. With a offset > > spindle to the right of center (say 3/8") of the > pod. The > > counter-clockwise force will tighten the belt. > > Way cool Uh. Now at full speed if the belt starts > to slip there will be > > less torque applied and thus less tension, > > now you may have tension runaway. So you may need > to add a little weight > > for insurance. Or just reconfigure > > it where less torque will give more tension by > using a string and weight > > to bias the pod in a clockwise direction, > > with the spindle to the left of center now. The > torque is now opposing the > > weight and if the belt starts to slip > > there will be less torque to counter the weight > and the weight will > > tighten the belt. But this config. may have > > a lot of slippage at startup because of higher > friction (thus higher > > torque fighting the weight) caused by the belt > slowly moving. > > But once up to speed it should work perfect. > > > > Happy confusions, > > Stan > > > > > > At 03:17 PM 3/6/2000 -0600, Stanley Goudge wrote: > > > Thats' right Igor's idea doesn't insure perfect > alignment,but with the > > right pulley may not have to. > > >Another concern I have is what happens at start > up, does the belt slip or > > will it grab causing the motor > > >to teeter toter back and forth on its pivot and > if its get too volent > > then it might cause the pod to move slightly, > > >which would loosen the belt. Guess we better make > the pod (stainless > > steel) pretty heavy just in case. > > >Guess it depends on the belt and weight used and > how much torque the > > motor has. We have unknowns here. > > > > > > I can see another idea that uses a offset > action to keep belt tension. > > By drilling a offset hole or holes > > >at the bottom of the pod and pivot this on a > dowel pin on the platform > > then using Igor's weight (heavier weight) > > >and string to rotate the pod, the offset (cam > action) would move the pod > > away from the platter tighting the belt. > > >Problem here of course is friction, and the only > cheap and easy way I can > > think of right now is a flat > > >polished surface on the bottom of the pod and > have it ride on 3 teflon > > pads affixed to the platform. > > >I think Igor's idea is still better from a > performance stand point, but > > just another idea. > > > > > >Stan > > > > > > > > > > > >At 12:26 PM 3/6/2000 -0700, Jon Lane wrote: > > >>> If the suggested bubble level was on the pod, > a glance > > >>> at it would tell you all need to know. It > would still > > >>> be vertical , or not. If the belt stretches > enough to > > >>> need touch up, the level could tell you, or > just look > > >>> to see where the belt is riding on the pulley. > > >>> > > >>> Igor > > >> > > >> > > >>Relatively speaking, the bubble level is a > low-precision, > > >>subjective evaluation of conditions. Machined > parts > > >>guarantee perfect alignment, on the other hand. > > >> > > >>Jon Lane > > >> > > > > __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: Re: [teres] isodamp Date: Mon, 13 Mar 2000 12:44:29 -0700 From: Stanley Goudge, Stanley Goudge To: teres@aiko.com; teres@aiko.com Igor, I was wondering what it would take to get a peek at your hand. Yea I like looks of the Clearaudio, but never heard any reviews or anything at all. Guess I'll have to call my buddy in Chicago and go to the CES this year. Unlike mountains which heights never change, in audio its an every day affair. I still got my old Souther arm, but like the ET One much better, so if tonearms are any indication of the "highest ground" then were on the wrong mountain. I well give the Souther desgin credit for having incredible air and transparency, but lacked low end. Maybe it didn't work well with Alpha one cartridge but never tried anything else. Fact is, acrylic designs can be mass produced cheaper than SS. So your augment here is pointless. Unless of corse if acrylic designs are superior then all TT would be made this way(cheaper and better). Now, where is the high ground? Stan P.S. Anyone going to CES this year? http://www3.50megs.com/engchye/turntable.htm At 08:14 AM 3/13/2000 -0800, Igor Kuznetsoff wrote: >Stan, > While the use of the isodamp does seem to be an >excellent idea for use on the platter, as well as for >correcting the ringing of metals as much as is >possible, it might be interesting to take a look at >that "highest ground" which, if (always) arguably >appears to presently be held by the Clearaudio TT, >picture attached below. No metal anywhere in the >chassis structure. It could well be that SS & Al are >materials of (medium to) *mass production* choice. > > Igor > >--- Stanley Goudge wrote: >> Alvin, >> The isodamp thing started with someone giving us >> the idea the platter needs to be >> damped, so I suggested the Well Tempered approach by >> using isodamp at the bottom >> of the platter. From there we figured it can and >> will be used in some subchassis and armboard >> designs. At this point its every man for himself in >> regards to this area. My plea for the use >> of SS in CLD has caused concerns in the lossy camp, >> however this was not my intensions, >> only to inject another idea, one that cannot be >> executed by table saw or router as is the case with >> most lossy designs. BTW most TT designers begin with >> a lossy design only to upgrade or >> redesign using more rigid materials, SS or aluminum >> seem to be materials of choice, not only >> for TT but tonearms as well. The lossy route is well >> travelled and I believe their are better >> routes which will lead us to much higher ground. >> >> Stan >> >> >> >> >> At 03:15 PM 3/12/2000 -0500, Alvin Richardson wrote: >> >Gents, >> >I am relatively new to the digest, and I try to >> keep up with what is going >> >on, although with too many different forums going >> on at once, it is >> >difficult to know what is being done. In this >> instance it would appear that >> >this purchase is being made apart from the general >> consensus. My question >> >is, how is this contributing to the making of the >> teres? I am assuming that >> >it is in reference to damping the subchassis. Am I >> correct? If it will >> >contribute to making my table that much better, I >> would hate to miss out. >> >The sizes/quantities being ordered, will this >> correspond to the finished >> >size of the subchassis? Thanks! al>> >> > >> >>From: Stanley Goudge >> >>Reply-To: teres@aiko.com >> >>To: teres@aiko.com >> >>Subject: [teres] isodamp >> >>Date: Fri, 10 Mar 2000 10:41:19 -0600 >> >> >> >>Heres the latest list for the isodamp order. >> Deadline is this Monday >> >>3-13 to get some. I'm too lazy or too busy (pick >> one) to fiqure exact >> >>shipping so I'll add $10 for packing each order + >> $1 per pound for UPS >> >>gound. >> >>The quoted prices did not include my shipping >> costs for receiving. I'll >> >>just include >> >>it in the $10. Personal checks ok. >> >> >> >> >> >>Jon Lane 16" square CN-12 single side peel and >> stick >> >>$11.50 + $1 x 1.6 lbs + $10 = $23.10 >> >> >> >>Paul Croft 3 X 1' x 1' tiles CN-38 single side >> peel and stick >> >>$37.58 + $1 x 8.1 lbs + $10 = $55.68 >> >> >> >>Scott Frazer 6 x 1' x1' tiles CN-12 single side >> peel and stick >> >>$33.84 + $1 x 5.5 lbs + $10 = $49.34 >> >> >> >>Maughan Audio 2 x 1' x 1' tiles CN-38 single >> side peel and stick >> >>$55.48 + $1 x 10.8 lbs + $10= $76.28 >> >> 2 x 1' x 1' tiles CN-38 >> double side peel and >> >>stick >> >> >> >> >> >> >> >>Stan Goudge >> >>1409 limestone ln. >> >>Cedar Park,TX 78613 >> >>512 250 0642 hm >> >>512 378 1505 wk >> >> >> > >> >>______________________________________________________ >> >Get Your Private, Free Email at >> http://www.hotmail.com >> > >> >> >__________________________________________________ >Do You Yahoo!? >Talk to your friends online with Yahoo! Messenger. >http://im.yahoo.com > Subject: RE: [teres] Motor Pod Date: Mon, 13 Mar 2000 13:02:11 -0700 From: Stanley Goudge, Stanley Goudge To: teres@aiko.com; teres@aiko.com Igor, I never seriously considered using this method or any others for that matter. Just trying to address concerns of others without expressing my opinions. Its just fun stuff to ponder, right Igor. Stan At 08:57 AM 3/13/2000 -0800, Igor Kuznetsoff wrote: >Stan, > I echo Ken's thought that this is an interesting >method, and one that I think can work. I do vaguely >remember seeing torque reaction systems used somewhere >to effect some control functions, but remember that >their action is rather *rough*, probably because the >highest torque exerted by electric motors is under >startup or stall conditions. This seems sure to cause >"hunting" problems, which could become difficult to >solve & may add complexity to what starts out with >some complexity already, that being one of my concerns >with this plan. Finally, This would require the use >of a bearing (maybe even more than one by the time >stable function is realized), and this would >compromise the tight coupling optimal to sinking motor >noise. Still, this is an intriguing idea, and I would >be curious to see how it works, should you choose to >follow it up. > > Igor > >"Schei, Kenneth" wrote: >> Stan: >> >> You propose a very interesting method. However, I >> respectfully think that >> using gravity via a counterweight or the weight of >> the motor pod on an >> eccentric support would be simpler and better. >> Using gravity would assure >> that there was no "hunting," because gravity is >> constant and non-reacting >> (at least on the Newtonian level). I don't envision >> any problem with motor >> axis misalignment because the amount of rotation to >> maintain belt tension >> would be mininal. >> >> Cheers, Ken >> >> Ken Schei, P.E. >> Project Engineer >> Antarctic Support Associates >> Email address: scheike@asa.org >> Phone: 303-643-0163 >> >> > -----Original Message----- >> > From: Stanley Goudge [SMTP:sgoudge@cisco.com] >> > Sent: Monday, March 06, 2000 7:33 PM >> > To: teres@aiko.com; teres@aiko.com; teres@aiko.com >> > Subject: RE: [teres] Motor Pod >> > >> > Sorry Guys, >> > I just can't leave this thing alone. You'll >> need paper & pencil to >> > figure this one. Forget what I said below, >> > after further thoughts it should be possible to >> use the torque of the >> > motor to tighten the belt automatically. >> > All that is needed is a thust bearing to allow >> the motor pod to rotate >> > freely. >> > Ok picture this, your looking down the left side >> of the turntable with >> > motor in the foregound and platter in the >> background. >> > Now the motor spins clockwise which creates a >> counter-clockwise torque on >> > the pod. With a offset >> > spindle to the right of center (say 3/8") of the >> pod. The >> > counter-clockwise force will tighten the belt. >> > Way cool Uh. Now at full speed if the belt starts >> to slip there will be >> > less torque applied and thus less tension, >> > now you may have tension runaway. So you may need >> to add a little weight >> > for insurance. Or just reconfigure >> > it where less torque will give more tension by >> using a string and weight >> > to bias the pod in a clockwise direction, >> > with the spindle to the left of center now. The >> torque is now opposing the >> > weight and if the belt starts to slip >> > there will be less torque to counter the weight >> and the weight will >> > tighten the belt. But this config. may have >> > a lot of slippage at startup because of higher >> friction (thus higher >> > torque fighting the weight) caused by the belt >> slowly moving. >> > But once up to speed it should work perfect. >> > >> > Happy confusions, >> > Stan >> > >> > >> > At 03:17 PM 3/6/2000 -0600, Stanley Goudge wrote: >> > > Thats' right Igor's idea doesn't insure perfect >> alignment,but with the >> > right pulley may not have to. >> > >Another concern I have is what happens at start >> up, does the belt slip or >> > will it grab causing the motor >> > >to teeter toter back and forth on its pivot and >> if its get too volent >> > then it might cause the pod to move slightly, >> > >which would loosen the belt. Guess we better make >> the pod (stainless >> > steel) pretty heavy just in case. >> > >Guess it depends on the belt and weight used and >> how much torque the >> > motor has. We have unknowns here. >> > > >> > > I can see another idea that uses a offset >> action to keep belt tension. >> > By drilling a offset hole or holes >> > >at the bottom of the pod and pivot this on a >> dowel pin on the platform >> > then using Igor's weight (heavier weight) >> > >and string to rotate the pod, the offset (cam >> action) would move the pod >> > away from the platter tighting the belt. >> > >Problem here of course is friction, and the only >> cheap and easy way I can >> > think of right now is a flat >> > >polished surface on the bottom of the pod and >> have it ride on 3 teflon >> > pads affixed to the platform. >> > >I think Igor's idea is still better from a >> performance stand point, but >> > just another idea. >> > > >> > >Stan >> > > >> > > >> > > >> > >At 12:26 PM 3/6/2000 -0700, Jon Lane wrote: >> > >>> If the suggested bubble level was on the pod, >> a glance >> > >>> at it would tell you all need to know. It >> would still >> > >>> be vertical , or not. If the belt stretches >> enough to >> > >>> need touch up, the level could tell you, or >> just look >> > >>> to see where the belt is riding on the pulley. >> > >>> >> > >>> Igor >> > >> >> > >> >> > >>Relatively speaking, the bubble level is a >> low-precision, >> > >>subjective evaluation of conditions. Machined >> parts >> > >>guarantee perfect alignment, on the other hand. >> > >> >> > >>Jon Lane >> > >> >> > > >> >__________________________________________________ >Do You Yahoo!? >Talk to your friends online with Yahoo! Messenger. >http://im.yahoo.com > Subject: Re: [teres] isodamp Date: Mon, 13 Mar 2000 19:12:52 -0700 From: MaughanAudio@aol.com, MaughanAudio@aol.com To: teres@aiko.com The Clearaudio is an excellent design, but I don't think it is the use of acrylic that makes it so. The use of acrylic does make it a striking visual piece. The use of such a thick platter, the use of a "Y" shaped plinth support, the use of massive brass support/suspension pods are things that add to it's overall quality of performance. I had a chance to watch it perform at the LasVegas CES and thought that this designs weakest link was the tonearm. It was an ingenious design that had very low mass and thus allowed it to track huge eccentricities and wraps. But I suspect that it would not effectively decouple stylus movement in the lower audio frequencies unless a very compliant and somewhat massive cartridge was used. Until again, Gordon Subject: Re: [teres] isodamp Date: Tue, 14 Mar 2000 00:31:33 -0700 From: Igor Kuznetsoff, Igor Kuznetsoff To: teres@aiko.com Stan, TAS featured it on their cover of issue 121 (Dec.'99/Jan. '00) & called it their "first 5-Star Component". There is a short writeup by HP. I suppose they must have also have done a full review of it in another issue, but I don't know which as I don't have a regular subscription. There is mention of the Souther's being an "improved" version. There is a possibility that I may hear it, in HP's own listening room. If that happens, I'll let you know what I thought, but don't hold your breath, it may never happen. I don't plan to use an acrylic chassis. I only used the Clearaudio as an example (plus I happened to have a picture handy, and it's pretty). I don't see how you figure that acrylic can be produced more cheaply than SS, which can be stamped out in high production, when acrylic needs hand finishing on every piece. But, then, I don't figure that price itself is the determining factor in making things sound good. It only limits the use of expensive materials that *could* sound good. Cost doesn't make "high ground", just "high price". Igor --- Stanley Goudge wrote: > Igor, > I was wondering what it would take to get a peek > at your hand. Yea I like looks of the Clearaudio, > but never heard any reviews or anything at all. > Guess I'll have to call my buddy in Chicago and go > to the CES this year. > Unlike mountains which heights never change, in > audio its an every day affair. > I still got my old Souther arm, but like the ET One > much better, so if tonearms are any > indication of the "highest ground" then were on the > wrong mountain. > I well give the Souther desgin credit for having > incredible air and transparency, but lacked > low end. Maybe it didn't work well with Alpha one > cartridge but never tried anything else. > > Fact is, acrylic designs can be mass produced > cheaper than SS. So your augment here is pointless. > Unless of corse if acrylic designs are superior then > all TT would be made this way(cheaper and better). > Now, where is the high ground? > > Stan > > P.S. Anyone going to CES this year? > http://www3.50megs.com/engchye/turntable.htm > > > At 08:14 AM 3/13/2000 -0800, Igor Kuznetsoff wrote: > >Stan, > > While the use of the isodamp does seem to be > an > >excellent idea for use on the platter, as well as > for > >correcting the ringing of metals as much as is > >possible, it might be interesting to take a look at > >that "highest ground" which, if (always) arguably > >appears to presently be held by the Clearaudio TT, > >picture attached below. No metal anywhere in the > >chassis structure. It could well be that SS & Al > are > >materials of (medium to) *mass production* choice. > > > > Igor > > > >--- Stanley Goudge wrote: > >> Alvin, > >> The isodamp thing started with someone giving > us > >> the idea the platter needs to be > >> damped, so I suggested the Well Tempered approach > by > >> using isodamp at the bottom > >> of the platter. From there we figured it can and > >> will be used in some subchassis and armboard > >> designs. At this point its every man for himself > in > >> regards to this area. My plea for the use > >> of SS in CLD has caused concerns in the lossy > camp, > >> however this was not my intensions, > >> only to inject another idea, one that cannot be > >> executed by table saw or router as is the case > with > >> most lossy designs. BTW most TT designers begin > with > >> a lossy design only to upgrade or > >> redesign using more rigid materials, SS or > aluminum > >> seem to be materials of choice, not only > >> for TT but tonearms as well. The lossy route is > well > >> travelled and I believe their are better > >> routes which will lead us to much higher ground. > >> > >> Stan > >> > >> > >> > >> > >> At 03:15 PM 3/12/2000 -0500, Alvin Richardson > wrote: > >> >Gents, > >> >I am relatively new to the digest, and I try to > >> keep up with what is going > >> >on, although with too many different forums > going > >> on at once, it is > >> >difficult to know what is being done. In this > >> instance it would appear that > >> >this purchase is being made apart from the > general > >> consensus. My question > >> >is, how is this contributing to the making of > the > >> teres? I am assuming that > >> >it is in reference to damping the subchassis. Am > I > >> correct? If it will > >> >contribute to making my table that much better, > I > >> would hate to miss out. > >> >The sizes/quantities being ordered, will this > >> correspond to the finished > >> >size of the subchassis? Thanks! al>> > >> > > >> >>From: Stanley Goudge > >> >>Reply-To: teres@aiko.com > >> >>To: teres@aiko.com > >> >>Subject: [teres] isodamp > >> >>Date: Fri, 10 Mar 2000 10:41:19 -0600 > >> >> > >> >>Heres the latest list for the isodamp order. > >> Deadline is this Monday > >> >>3-13 to get some. I'm too lazy or too busy > (pick > >> one) to fiqure exact > >> >>shipping so I'll add $10 for packing each order > + > >> $1 per pound for UPS > >> >>gound. > >> >>The quoted prices did not include my shipping > >> costs for receiving. I'll > >> >>just include > >> >>it in the $10. Personal checks ok. > >> >> > >> >> > >> >>Jon Lane 16" square CN-12 single side peel and > >> stick > >> >>$11.50 + $1 x 1.6 lbs + $10 = $23.10 > >> >> > >> >>Paul Croft 3 X 1' x 1' tiles CN-38 single side > >> peel and stick > >> >>$37.58 + $1 x 8.1 lbs + $10 = $55.68 > >> >> > >> >>Scott Frazer 6 x 1' x1' tiles CN-12 single > side > >> peel and stick > >> >>$33.84 + $1 x 5.5 lbs + $10 = $49.34 > >> >> > >> >>Maughan Audio 2 x 1' x 1' tiles CN-38 single > >> side peel and stick > >> >>$55.48 + $1 x 10.8 lbs + $10= $76.28 > >> >> 2 x 1' x 1' tiles > CN-38 > >> double side peel and > >> >>stick > >> >> > >> >> > >> >> > >> >>Stan Goudge > >> >>1409 limestone ln. > >> >>Cedar Park,TX 78613 > >> >>512 250 0642 hm > >> >>512 378 1505 wk > >> >> > >> > > >> > >>______________________________________________________ > >> >Get Your Private, Free Email at > >> http://www.hotmail.com > >> > > >> > >> > >__________________________________________________ > >Do You Yahoo!? > >Talk to your friends online with Yahoo! Messenger. > >http://im.yahoo.com > > > > __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: Re: [teres] isodamp Date: Tue, 14 Mar 2000 01:26:03 -0700 From: Igor Kuznetsoff, Igor Kuznetsoff To: teres@aiko.com I agree, it is not likely to be any one thing, but, rather, how it is all put together that really makes a *design*. Igor --- MaughanAudio@aol.com wrote: > The Clearaudio is an excellent design, but I don't > think it is the use of > acrylic that makes it so. The use of acrylic does > make it a striking visual > piece. The use of such a thick platter, the use of a > "Y" shaped plinth > support, the use of massive brass support/suspension > pods are things that add > to it's overall quality of performance. > I had a chance to watch it perform at the > LasVegas CES and thought that > this designs weakest link was the tonearm. It was an > ingenious design that > had very low mass and thus allowed it to track huge > eccentricities and wraps. > But I suspect that it would not effectively decouple > stylus movement in the > lower audio frequencies unless a very compliant and > somewhat massive > cartridge was used. > > Until again, Gordon > __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: RE: [teres] isodamp; lossy approach is not the best? Date: Tue, 14 Mar 2000 08:28:38 -0700 From: Jon Lane, Jon Lane To: teres@aiko.com Two reasons. 1. The mechanical loop needs to be as lossless as possible otherwise tiny internal bending ("resonance" being the trendy audiophile word for this) interrupts the ability for all energy to appear at all places. If the latter does not occur, logically we can see how this energy would be localized through inadequate transmission. 2. Directly pursuant to this (or perhaps as just a different interpretation of the same thing), just as the 3" acrylic is used to ensure a mechanical impedance match between vinyl and platter for reasons of sinking resonance (or high coupling if you prefer to see it that way), the use of a thick alloy base is only one option that can do the same sinking for the tonearm. Once again, any interruption of the loop obscures the retrieval of fine detail. SOTA's and Maplenol's have the sonic "blackness" of a quiet, heavy design, but neither has the detail and focus of a Linn or Oracle, the latter two going to pains to maximize the mechanical loop. The SOTA decouples the parts with liberal use of lead and pressboard including a thin armboard, the Maplenol is a completely decoupled airbearing; while the Linn is rigid steel and hardboard, and the Oracle mostly heavy alloy. The mother of all coupled loop designs was the Goldmund, and was almost universally regarded for the depth of it's information retrieval. I explored the two philosophies over ten years ago and IMO, the rigid loop blew the lossy subchassis completely away. If you'll permit an unabashed opinion, I think too much attention is paid to obsessing over stopping "resonance" before it starts and not enough to coupling the essential components as tightly as possible. One thing to bear in mind is that there is literally no place for *internal* resonance to come from outside of the stylus/record interface which encounters the 3" platter immediately. The platter-to-base-to-arm loop is dead quiet with a bearing of this caliber, and the motor is completely isolated. Or certainly should be. This leaves only out-of-system energy needing attention and this is dealt with via sandbox or what have you, all being accessories to the basic machine. The use of a fundamentally lossy, bendy material (plexiglas, in the case of the highly cosmetic designs) just begs for decoupling/bending to the point that any energy found in these parts is going to stay reactive longer, lower in frequency, and local to its origin and will subtly color the proceedings. OTOH, as the theory goes, energy found in a heavy, rigid, "conductive" chassis naturally appears "everyplace" in the structure with a minimum of resonant bending, and can be damped critically after the fact as the designer wishes. Further, the sheer rigid mass couples all the way back into the arm and bearing themselves, attenuating their contribution to the vibrational soup - lossy chassis cannot do this, leaving either or both to their own devices. As a speaker designer, I see this analogous to never being able to critically damp a undersized box, but being able to critically damp an oversized box by reducing it's Q. While the analogy appears inverted, the notion is that one can design with the intention of critical damping after the fact. Apologies for the overt editorial, but I felt this was still an area of mixed understanding. Jon Lane > -----Original Message----- > From: owner-teres@aiko.com > [mailto:owner-teres@aiko.com]On Behalf Of > Sellek, Grant (TSA) > Sent: Tuesday, March 14, 2000 2:47 AM > To: 'teres@aiko.com' > Subject: RE: [teres] isodamp; lossy approach is > not the best? > > > What is the essential nature of the discontent > with the "lossy" approach? > > I cannot imagine why "more rigid materials" > should be cause for celebration, > unless one was upgrading from a relatively > lightweight lossy approach (dare > I say a "floppy" approach) to a more massive > rigid approach. I can see how > this may be an upgrade. But I cannot see why a > massive, lossy approach > should be flawed. > > Any takers? > > > Grant Sellek > Adelaide, Australia > grant.sellek@transport.sa.gov.au Subject: Re: [teres] isodamp Date: Tue, 14 Mar 2000 09:51:30 -0700 From: Stanley Goudge, Stanley Goudge To: teres@aiko.com; teres@aiko.com Igor, I'm sure the Clearaudio is world class, sure looks it anyway. How about that Spj la luce TT, looks cool, but owning a TT designed by a women....well I don't know. BTW I heard rumors from Sota that HP's new reference is the SOTA millennium and a review is in the works. Not sure where this puts us, as I think the Sota combines rigidity and lossy componets. I hope you get the chance to find out first hand. My main concern about acrylic was that anyone can build there own either buy cutting with a table saw and router or having a plastics supply house cut it for you. This stuff is easy to cut and you can buy special blades from Forest (10" $200, Ouch). I'm assuming that Chris's brother is willing to machine the subchassis, mayby I'm wrong here. If my assumption is correct then its a waste to machine plastics for a subchassis using CNC. If we did then we'll have missed the opportunity to find out which design works better for our system. I sure can't cut SS or AL with a tablesaw. If my assumption is incorrect then there is not much more to say on it. As to stamped SS, most of the TT I'm thinking of have machined SS componets. Stan http://www4.50megs.com/turntable/tg.htm At 10:19 PM 3/13/2000 -0800, Igor Kuznetsoff wrote: >Stan, > TAS featured it on their cover of issue 121 >(Dec.'99/Jan. '00) & called it their "first 5-Star >Component". There is a short writeup by HP. I >suppose they must have also have done a >full review of it in another issue, but I don't know >which as I don't have a regular subscription. There >is mention of the Souther's being an "improved" >version. There is a possibility that I may hear it, >in HP's own listening room. If that happens, I'll let >you know what I thought, but don't hold your breath, >it may never happen. > I don't plan to use an acrylic chassis. I only >used the Clearaudio as an example (plus I happened to >have a picture handy, and it's pretty). > I don't see how you figure that acrylic can be >produced more cheaply than SS, which can be stamped >out in high production, when acrylic needs hand >finishing on every piece. But, then, I don't figure >that price itself is the determining factor in making >things sound good. It only limits the use of >expensive materials that *could* sound good. Cost >doesn't make "high ground", just "high price". > > Igor > >--- Stanley Goudge wrote: >> Igor, >> I was wondering what it would take to get a peek >> at your hand. Yea I like looks of the Clearaudio, >> but never heard any reviews or anything at all. >> Guess I'll have to call my buddy in Chicago and go >> to the CES this year. >> Unlike mountains which heights never change, in >> audio its an every day affair. >> I still got my old Souther arm, but like the ET One >> much better, so if tonearms are any >> indication of the "highest ground" then were on the >> wrong mountain. >> I well give the Souther desgin credit for having >> incredible air and transparency, but lacked >> low end. Maybe it didn't work well with Alpha one >> cartridge but never tried anything else. >> >> Fact is, acrylic designs can be mass produced >> cheaper than SS. So your augment here is pointless. >> Unless of corse if acrylic designs are superior then >> all TT would be made this way(cheaper and better). >> Now, where is the high ground? >> >> Stan >> >> P.S. Anyone going to CES this year? >> http://www3.50megs.com/engchye/turntable.htm >> >> >> At 08:14 AM 3/13/2000 -0800, Igor Kuznetsoff wrote: >> >Stan, >> > While the use of the isodamp does seem to be >> an >> >excellent idea for use on the platter, as well as >> for >> >correcting the ringing of metals as much as is >> >possible, it might be interesting to take a look at >> >that "highest ground" which, if (always) arguably >> >appears to presently be held by the Clearaudio TT, >> >picture attached below. No metal anywhere in the >> >chassis structure. It could well be that SS & Al >> are >> >materials of (medium to) *mass production* choice. >> > >> > Igor >> > >> >--- Stanley Goudge wrote: >> >> Alvin, >> >> The isodamp thing started with someone giving >> us >> >> the idea the platter needs to be >> >> damped, so I suggested the Well Tempered approach >> by >> >> using isodamp at the bottom >> >> of the platter. From there we figured it can and >> >> will be used in some subchassis and armboard >> >> designs. At this point its every man for himself >> in >> >> regards to this area. My plea for the use >> >> of SS in CLD has caused concerns in the lossy >> camp, >> >> however this was not my intensions, >> >> only to inject another idea, one that cannot be >> >> executed by table saw or router as is the case >> with >> >> most lossy designs. BTW most TT designers begin >> with >> >> a lossy design only to upgrade or >> >> redesign using more rigid materials, SS or >> aluminum >> >> seem to be materials of choice, not only >> >> for TT but tonearms as well. The lossy route is >> well >> >> travelled and I believe their are better >> >> routes which will lead us to much higher ground. >> >> >> >> Stan >> >> >> >> >> >> >> >> >> >> At 03:15 PM 3/12/2000 -0500, Alvin Richardson >> wrote: >> >> >Gents, >> >> >I am relatively new to the digest, and I try to >> >> keep up with what is going >> >> >on, although with too many different forums >> going >> >> on at once, it is >> >> >difficult to know what is being done. In this >> >> instance it would appear that >> >> >this purchase is being made apart from the >> general >> >> consensus. My question >> >> >is, how is this contributing to the making of >> the >> >> teres? I am assuming that >> >> >it is in reference to damping the subchassis. Am >> I >> >> correct? If it will >> >> >contribute to making my table that much better, >> I >> >> would hate to miss out. >> >> >The sizes/quantities being ordered, will this >> >> correspond to the finished >> >> >size of the subchassis? Thanks! al>> >> >> > >> >> >>From: Stanley Goudge >> >> >>Reply-To: teres@aiko.com >> >> >>To: teres@aiko.com >> >> >>Subject: [teres] isodamp >> >> >>Date: Fri, 10 Mar 2000 10:41:19 -0600 >> >> >> >> >> >>Heres the latest list for the isodamp order. >> >> Deadline is this Monday >> >> >>3-13 to get some. I'm too lazy or too busy >> (pick >> >> one) to fiqure exact >> >> >>shipping so I'll add $10 for packing each order >> + >> >> $1 per pound for UPS >> >> >>gound. >> >> >>The quoted prices did not include my shipping >> >> costs for receiving. I'll >> >> >>just include >> >> >>it in the $10. Personal checks ok. >> >> >> >> >> >> >> >> >>Jon Lane 16" square CN-12 single side peel and >> >> stick >> >> >>$11.50 + $1 x 1.6 lbs + $10 = $23.10 >> >> >> >> >> >>Paul Croft 3 X 1' x 1' tiles CN-38 single side >> >> peel and stick >> >> >>$37.58 + $1 x 8.1 lbs + $10 = $55.68 >> >> >> >> >> >>Scott Frazer 6 x 1' x1' tiles CN-12 single >> side >> >> peel and stick >> >> >>$33.84 + $1 x 5.5 lbs + $10 = $49.34 >> >> >> >> >> >>Maughan Audio 2 x 1' x 1' tiles CN-38 single >> >> side peel and stick >> >> >>$55.48 + $1 x 10.8 lbs + $10= $76.28 >> >> >> 2 x 1' x 1' tiles >> CN-38 >> >> double side peel and >> >> >>stick >> >> >> >> >> >> >> >> >> >> >> >>Stan Goudge >> >> >>1409 limestone ln. >> >> >>Cedar Park,TX 78613 >> >> >>512 250 0642 hm >> >> >>512 378 1505 wk >> >> >> >> >> > >> >> >> >>>______________________________________________________ >> >> >Get Your Private, Free Email at >> >> http://www.hotmail.com >> >> > >> >> >> >> >> >__________________________________________________ >> >Do You Yahoo!? >> >Talk to your friends online with Yahoo! Messenger. >> >http://im.yahoo.com >> > >> >> >__________________________________________________ >Do You Yahoo!? >Talk to your friends online with Yahoo! Messenger. >http://im.yahoo.com > Subject: RE: [teres] isodamp; lossy approach is not the best? Date: Tue, 14 Mar 2000 10:05:03 -0700 From: Schei, Kenneth, Schei, Kenneth To: 'teres@aiko.com' Jon: I've read your theses carefully, but I struggle with the statement "ability for all energy to appear at all places." That statement appears to violate the basic laws of physics as I understand them, and thus reduces the effectiveness of your arguement in my mind. Other points of your thesis also seem alien to me. You want a lossless mechanical loop; in my mind that would return energy sunk into it back to the stylus, only delayed as it travels through the loop. I can't help but think of that process as delayed feedback, which is loved by the transistor crowd but has no place in my life. That delayed feedback is probably why Linns and Oracles don't have the "blackness" of a SOTA or Maplenoll, as you point out. Correct me if I'm wrong, but I suspect that the resultant sound of a "bright" base would be brighter than that of a "lossy" system. One has to listen to decide if brighter is better. I remain allied to a "massive, lossy base," as Grant aptly described it. As an amateur speaker designer, I don't understand how you equate an undersize speaker boss to a lossy TT base. An undersize speaker boss has a high Q and requires more damping, just the opposite of a lossy base. As you say, the analogy is indeed inverted, but I'm unable to set it aright. I view our dissimilar philosophies as very constructive, especially in this format. Each of us will ultimately construct our TT bases according to our beliefs and tastes, and we can profit by the ideas of others in doing so. I only hope I have the opportunity to hear the results of different designs. Cheers, Ken Ken Schei, P.E. Project Engineer Antarctic Support Associates Email address: scheike@asa.org Phone: 303-643-0163 > -----Original Message----- > From: Jon Lane [SMTP:jhlane@email.msn.com] > Sent: Tuesday, March 14, 2000 7:23 AM > To: teres@aiko.com > Subject: RE: [teres] isodamp; lossy approach is not the best? > > Two reasons. > > 1. The mechanical loop needs to be as lossless as possible > otherwise tiny internal bending ("resonance" being the > trendy audiophile word for this) interrupts the ability for > all energy to appear at all places. If the latter does not > occur, logically we can see how this energy would be > localized through inadequate transmission. > > 2. Directly pursuant to this (or perhaps as just a > different interpretation of the same thing), just as the 3" > acrylic is used to ensure a mechanical impedance match > between vinyl and platter for reasons of sinking resonance > (or high coupling if you prefer to see it that way), the use > of a thick alloy base is only one option that can do the > same sinking for the tonearm. > > Once again, any interruption of the loop obscures the > retrieval of fine detail. SOTA's and Maplenol's have the > sonic "blackness" of a quiet, heavy design, but neither has > the detail and focus of a Linn or Oracle, the latter two > going to pains to maximize the mechanical loop. The SOTA > decouples the parts with liberal use of lead and pressboard > including a thin armboard, the Maplenol is a completely > decoupled airbearing; while the Linn is rigid steel and > hardboard, and the Oracle mostly heavy alloy. The mother of > all coupled loop designs was the Goldmund, and was almost > universally regarded for the depth of it's information > retrieval. > > I explored the two philosophies over ten years ago and IMO, > the rigid loop blew the lossy subchassis completely away. > If you'll permit an unabashed opinion, I think too much > attention is paid to obsessing over stopping "resonance" > before it starts and not enough to coupling the essential > components as tightly as possible. One thing to bear in > mind is that there is literally no place for *internal* > resonance to come from outside of the stylus/record > interface which encounters the 3" platter immediately. The > platter-to-base-to-arm loop is dead quiet with a bearing of > this caliber, and the motor is completely isolated. Or > certainly should be. This leaves only out-of-system energy > needing attention and this is dealt with via sandbox or what > have you, all being accessories to the basic machine. The > use of a fundamentally lossy, bendy material (plexiglas, in > the case of the highly cosmetic designs) just begs for > decoupling/bending to the point that any energy found in > these parts is going to stay reactive longer, lower in > frequency, and local to its origin and will subtly color the > proceedings. OTOH, as the theory goes, energy found in a > heavy, rigid, "conductive" chassis naturally appears > "everyplace" in the structure with a minimum of resonant > bending, and can be damped critically after the fact as the > designer wishes. Further, the sheer rigid mass couples all > the way back into the arm and bearing themselves, > attenuating their contribution to the vibrational soup - > lossy chassis cannot do this, leaving either or both to > their own devices. As a speaker designer, I see this > analogous to never being able to critically damp a > undersized box, but being able to critically damp an > oversized box by reducing it's Q. While the analogy appears > inverted, the notion is that one can design with the > intention of critical damping after the fact. > > Apologies for the overt editorial, but I felt this was still > an area of mixed understanding. > > Jon Lane > > > > -----Original Message----- > > From: owner-teres@aiko.com > > [mailto:owner-teres@aiko.com]On Behalf Of > > Sellek, Grant (TSA) > > Sent: Tuesday, March 14, 2000 2:47 AM > > To: 'teres@aiko.com' > > Subject: RE: [teres] isodamp; lossy approach is > > not the best? > > > > > > What is the essential nature of the discontent > > with the "lossy" approach? > > > > I cannot imagine why "more rigid materials" > > should be cause for celebration, > > unless one was upgrading from a relatively > > lightweight lossy approach (dare > > I say a "floppy" approach) to a more massive > > rigid approach. I can see how > > this may be an upgrade. But I cannot see why a > > massive, lossy approach > > should be flawed. > > > > Any takers? > > > > > > Grant Sellek > > Adelaide, Australia > > grant.sellek@transport.sa.gov.au > Subject: RE: [teres] isodamp; lossy approach is not the best? Date: Tue, 14 Mar 2000 10:15:38 -0700 From: Kalman Rubinson, Kalman Rubinson To: 'teres@aiko.com' On Tue, 14 Mar 2000, Sellek, Grant (TSA) wrote: > What is the essential nature of the discontent with the "lossy" approach? Most 'lossy' structures or materials are selectively lossy. If their frequency preferences are right for the application, that's fine. They may not be 'lossy' just where you need it. Kal Subject: RE: [teres] isodamp; lossy approach is not the best? Date: Tue, 14 Mar 2000 10:38:32 -0700 From: Igor Kuznetsoff, Igor Kuznetsoff To: teres@aiko.com A much quieter background would be achieved if "no energy appeared anyplace", except, of course, at the cartridge, the only place where it actually belongs. Igor --- "Schei, Kenneth" wrote: > Jon: > > I've read your theses carefully, but I struggle with > the statement "ability > for all energy to appear at all places." That > statement appears to violate > the basic laws of physics as I understand them, and > thus reduces the > effectiveness of your arguement in my mind. Other > points of your thesis > also seem alien to me. You want a lossless > mechanical loop; in my mind that > would return energy sunk into it back to the stylus, > only delayed as it > travels through the loop. I can't help but think of > that process as delayed > feedback, which is loved by the transistor crowd but > has no place in my > life. That delayed feedback is probably why Linns > and Oracles don't have > the "blackness" of a SOTA or Maplenoll, as you point > out. Correct me if I'm > wrong, but I suspect that the resultant sound of a > "bright" base would be > brighter than that of a "lossy" system. One has to > listen to decide if > brighter is better. I remain allied to a "massive, > lossy base," as Grant > aptly described it. > > As an amateur speaker designer, I don't understand > how you equate an > undersize speaker boss to a lossy TT base. An > undersize speaker boss has a > high Q and requires more damping, just the opposite > of a lossy base. As you > say, the analogy is indeed inverted, but I'm unable > to set it aright. > > I view our dissimilar philosophies as very > constructive, especially in this > format. Each of us will ultimately construct our TT > bases according to our > beliefs and tastes, and we can profit by the ideas > of others in doing so. I > only hope I have the opportunity to hear the results > of different designs. > > Cheers, Ken > > Ken Schei, P.E. > Project Engineer > Antarctic Support Associates > Email address: scheike@asa.org > Phone: 303-643-0163 > > > -----Original Message----- > > From: Jon Lane [SMTP:jhlane@email.msn.com] > > Sent: Tuesday, March 14, 2000 7:23 AM > > To: teres@aiko.com > > Subject: RE: [teres] isodamp; lossy approach is > not the best? > > > > Two reasons. > > > > 1. The mechanical loop needs to be as lossless as > possible > > otherwise tiny internal bending ("resonance" being > the > > trendy audiophile word for this) interrupts the > ability for > > all energy to appear at all places. If the latter > does not > > occur, logically we can see how this energy would > be > > localized through inadequate transmission. > > > > 2. Directly pursuant to this (or perhaps as just > a > > different interpretation of the same thing), just > as the 3" > > acrylic is used to ensure a mechanical impedance > match > > between vinyl and platter for reasons of sinking > resonance > > (or high coupling if you prefer to see it that > way), the use > > of a thick alloy base is only one option that can > do the > > same sinking for the tonearm. > > > > Once again, any interruption of the loop obscures > the > > retrieval of fine detail. SOTA's and Maplenol's > have the > > sonic "blackness" of a quiet, heavy design, but > neither has > > the detail and focus of a Linn or Oracle, the > latter two > > going to pains to maximize the mechanical loop. > The SOTA > > decouples the parts with liberal use of lead and > pressboard > > including a thin armboard, the Maplenol is a > completely > > decoupled airbearing; while the Linn is rigid > steel and > > hardboard, and the Oracle mostly heavy alloy. The > mother of > > all coupled loop designs was the Goldmund, and was > almost > > universally regarded for the depth of it's > information > > retrieval. > > > > I explored the two philosophies over ten years ago > and IMO, > > the rigid loop blew the lossy subchassis > completely away. > > If you'll permit an unabashed opinion, I think too > much > > attention is paid to obsessing over stopping > "resonance" > > before it starts and not enough to coupling the > essential > > components as tightly as possible. One thing to > bear in > > mind is that there is literally no place for > *internal* > > resonance to come from outside of the > stylus/record > > interface which encounters the 3" platter > immediately. The > > platter-to-base-to-arm loop is dead quiet with a > bearing of > > this caliber, and the motor is completely > isolated. Or > > certainly should be. This leaves only > out-of-system energy > > needing attention and this is dealt with via > sandbox or what > > have you, all being accessories to the basic > machine. The > > use of a fundamentally lossy, bendy material > (plexiglas, in > > the case of the highly cosmetic designs) just begs > for > > decoupling/bending to the point that any energy > found in > > these parts is going to stay reactive longer, > lower in > > frequency, and local to its origin and will subtly > color the > > proceedings. OTOH, as the theory goes, energy > found in a > > heavy, rigid, "conductive" chassis naturally > appears > > "everyplace" in the structure with a minimum of > resonant > > bending, and can be damped critically after the > fact as the > > designer wishes. Further, the sheer rigid mass > couples all > > the way back into the arm and bearing themselves, > > attenuating their contribution to the vibrational > soup - > > lossy chassis cannot do this, leaving either or > both to > > their own devices. As a speaker designer, I see > this > > analogous to never being able to critically damp a > > undersized box, but being able to critically damp > an > > oversized box by reducing it's Q. While the > analogy appears > > inverted, the notion is that one can design with > the > > intention of critical damping after the fact. > > > > Apologies for the overt editorial, but I felt this > was still > > an area of mixed understanding. > > > > Jon Lane > > > > > > > -----Original Message----- > > > From: owner-teres@aiko.com > > > [mailto:owner-teres@aiko.com]On Behalf Of > > > Sellek, Grant (TSA) > > > Sent: Tuesday, March 14, 2000 2:47 AM > > > To: 'teres@aiko.com' > > > Subject: RE: [teres] isodamp; lossy approach is > > > not the best? > > > > > > > > > What is the essential nature of the discontent > > > with the "lossy" approach? > > > > > > I cannot imagine why "more rigid materials" > > > should be cause for celebration, > === message truncated === __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: RE: [teres] isodamp Date: Tue, 14 Mar 2000 10:57:28 -0700 From: Mackris, Thom G., Mackris, Thom G. To: 'teres@aiko.com' No time for details at the moment, but a conversation with Doc Bottlehead at ny Noise was quite interesting. He's found a resinous / silica based compoud which casts very easily and is extriadinarily dead. I'm in Jon Lane's and Chris's camp on first getting a perfect energy loop between bearing and tonearm and I'm not sure how this stuff fits into the overall plan. Regarding casting, Chris mentioned that acrylic is not all that difficult to cast. Chris had an interesting idea - routing a recess for an extremely rigid plate that runs from the bearing to the arm mounting area. Thom -----Original Message----- From: Stanley Goudge [mailto:sgoudge@cisco.com] Sent: Tuesday, March 14, 2000 8:44 AM To: teres@aiko.com; teres@aiko.com Subject: Re: [teres] isodamp Igor, I'm sure the Clearaudio is world class, sure looks it anyway. How about that Spj la luce TT, looks cool, but owning a TT designed by a women....well I don't know. BTW I heard rumors from Sota that HP's new reference is the SOTA millennium and a review is in the works. Not sure where this puts us, as I think the Sota combines rigidity and lossy componets. I hope you get the chance to find out first hand. My main concern about acrylic was that anyone can build there own either buy cutting with a table saw and router or having a plastics supply house cut it for you. This stuff is easy to cut and you can buy special blades from Forest (10" $200, Ouch). I'm assuming that Chris's brother is willing to machine the subchassis, mayby I'm wrong here. If my assumption is correct then its a waste to machine plastics for a subchassis using CNC. If we did then we'll have missed the opportunity to find out which design works better for our system. I sure can't cut SS or AL with a tablesaw. If my assumption is incorrect then there is not much more to say on it. As to stamped SS, most of the TT I'm thinking of have machined SS componets. Stan http://www4.50megs.com/turntable/tg.htm At 10:19 PM 3/13/2000 -0800, Igor Kuznetsoff wrote: >Stan, > TAS featured it on their cover of issue 121 >(Dec.'99/Jan. '00) & called it their "first 5-Star >Component". There is a short writeup by HP. I >suppose they must have also have done a >full review of it in another issue, but I don't know >which as I don't have a regular subscription. There >is mention of the Souther's being an "improved" >version. There is a possibility that I may hear it, >in HP's own listening room. If that happens, I'll let >you know what I thought, but don't hold your breath, >it may never happen. > I don't plan to use an acrylic chassis. I only >used the Clearaudio as an example (plus I happened to >have a picture handy, and it's pretty). > I don't see how you figure that acrylic can be >produced more cheaply than SS, which can be stamped >out in high production, when acrylic needs hand >finishing on every piece. But, then, I don't figure >that price itself is the determining factor in making >things sound good. It only limits the use of >expensive materials that *could* sound good. Cost >doesn't make "high ground", just "high price". > > Igor > >--- Stanley Goudge wrote: >> Igor, >> I was wondering what it would take to get a peek >> at your hand. Yea I like looks of the Clearaudio, >> but never heard any reviews or anything at all. >> Guess I'll have to call my buddy in Chicago and go >> to the CES this year. >> Unlike mountains which heights never change, in >> audio its an every day affair. >> I still got my old Souther arm, but like the ET One >> much better, so if tonearms are any >> indication of the "highest ground" then were on the >> wrong mountain. >> I well give the Souther desgin credit for having >> incredible air and transparency, but lacked >> low end. Maybe it didn't work well with Alpha one >> cartridge but never tried anything else. >> >> Fact is, acrylic designs can be mass produced >> cheaper than SS. So your augment here is pointless. >> Unless of corse if acrylic designs are superior then >> all TT would be made this way(cheaper and better). >> Now, where is the high ground? >> >> Stan >> >> P.S. Anyone going to CES this year? >> http://www3.50megs.com/engchye/turntable.htm >> >> >> At 08:14 AM 3/13/2000 -0800, Igor Kuznetsoff wrote: >> >Stan, >> > While the use of the isodamp does seem to be >> an >> >excellent idea for use on the platter, as well as >> for >> >correcting the ringing of metals as much as is >> >possible, it might be interesting to take a look at >> >that "highest ground" which, if (always) arguably >> >appears to presently be held by the Clearaudio TT, >> >picture attached below. No metal anywhere in the >> >chassis structure. It could well be that SS & Al >> are >> >materials of (medium to) *mass production* choice. >> > >> > Igor >> > >> >--- Stanley Goudge wrote: >> >> Alvin, >> >> The isodamp thing started with someone giving >> us >> >> the idea the platter needs to be >> >> damped, so I suggested the Well Tempered approach >> by >> >> using isodamp at the bottom >> >> of the platter. From there we figured it can and >> >> will be used in some subchassis and armboard >> >> designs. At this point its every man for himself >> in >> >> regards to this area. My plea for the use >> >> of SS in CLD has caused concerns in the lossy >> camp, >> >> however this was not my intensions, >> >> only to inject another idea, one that cannot be >> >> executed by table saw or router as is the case >> with >> >> most lossy designs. BTW most TT designers begin >> with >> >> a lossy design only to upgrade or >> >> redesign using more rigid materials, SS or >> aluminum >> >> seem to be materials of choice, not only >> >> for TT but tonearms as well. The lossy route is >> well >> >> travelled and I believe their are better >> >> routes which will lead us to much higher ground. >> >> >> >> Stan >> >> >> >> >> >> >> >> >> >> At 03:15 PM 3/12/2000 -0500, Alvin Richardson >> wrote: >> >> >Gents, >> >> >I am relatively new to the digest, and I try to >> >> keep up with what is going >> >> >on, although with too many different forums >> going >> >> on at once, it is >> >> >difficult to know what is being done. In this >> >> instance it would appear that >> >> >this purchase is being made apart from the >> general >> >> consensus. My question >> >> >is, how is this contributing to the making of >> the >> >> teres? I am assuming that >> >> >it is in reference to damping the subchassis. Am >> I >> >> correct? If it will >> >> >contribute to making my table that much better, >> I >> >> would hate to miss out. >> >> >The sizes/quantities being ordered, will this >> >> correspond to the finished >> >> >size of the subchassis? Thanks! al>> >> >> > >> >> >>From: Stanley Goudge >> >> >>Reply-To: teres@aiko.com >> >> >>To: teres@aiko.com >> >> >>Subject: [teres] isodamp >> >> >>Date: Fri, 10 Mar 2000 10:41:19 -0600 >> >> >> >> >> >>Heres the latest list for the isodamp order. >> >> Deadline is this Monday >> >> >>3-13 to get some. I'm too lazy or too busy >> (pick >> >> one) to fiqure exact >> >> >>shipping so I'll add $10 for packing each order >> + >> >> $1 per pound for UPS >> >> >>gound. >> >> >>The quoted prices did not include my shipping >> >> costs for receiving. I'll >> >> >>just include >> >> >>it in the $10. Personal checks ok. >> >> >> >> >> >> >> >> >>Jon Lane 16" square CN-12 single side peel and >> >> stick >> >> >>$11.50 + $1 x 1.6 lbs + $10 = $23.10 >> >> >> >> >> >>Paul Croft 3 X 1' x 1' tiles CN-38 single side >> >> peel and stick >> >> >>$37.58 + $1 x 8.1 lbs + $10 = $55.68 >> >> >> >> >> >>Scott Frazer 6 x 1' x1' tiles CN-12 single >> side >> >> peel and stick >> >> >>$33.84 + $1 x 5.5 lbs + $10 = $49.34 >> >> >> >> >> >>Maughan Audio 2 x 1' x 1' tiles CN-38 single >> >> side peel and stick >> >> >>$55.48 + $1 x 10.8 lbs + $10= $76.28 >> >> >> 2 x 1' x 1' tiles >> CN-38 >> >> double side peel and >> >> >>stick >> >> >> >> >> >> >> >> >> >> >> >>Stan Goudge >> >> >>1409 limestone ln. >> >> >>Cedar Park,TX 78613 >> >> >>512 250 0642 hm >> >> >>512 378 1505 wk >> >> >> >> >> > >> >> >> >>>______________________________________________________ >> >> >Get Your Private, Free Email at >> >> http://www.hotmail.com >> >> > >> >> >> >> >> >__________________________________________________ >> >Do You Yahoo!? >> >Talk to your friends online with Yahoo! Messenger. >> >http://im.yahoo.com >> > >> >> >__________________________________________________ >Do You Yahoo!? >Talk to your friends online with Yahoo! Messenger. >http://im.yahoo.com > Subject: Re: [teres] isodamp Date: Tue, 14 Mar 2000 11:18:23 -0700 From: Igor Kuznetsoff, Igor Kuznetsoff To: teres@aiko.com Hi, Stan, I'm not familiar with the SPJ, but, well, women do generally have better hearing than men, and more women are showing up in engineering nowadays. The combination could result in an interesting new perspective. I just hope it doesn't come in "Peach". Where can I get a look at it? As to the Sota, well, it puts me, anyway, right where I've been all along on the rigid+lossy issue: it is precisely my philosophy, and has been for at least 10 years. I believe that both can be had, without the additional ringing of metal. (I don't know anything about the new Sota). Funny you should mention it just now, because I have a rough draft of a note on just that very thing, which I wrote last night, but was too tired to clean up for sending . Will try to sometime by tonight. Igor --- Stanley Goudge wrote: > Igor, > I'm sure the Clearaudio is world class, sure > looks it anyway. > How about that Spj la luce TT, looks cool, but > owning a TT designed > by a women....well I don't know. BTW I heard rumors > from Sota that HP's new > reference is the SOTA millennium and a review is in > the works. Not > sure where this puts us, as I think the Sota > combines rigidity and lossy > componets. I hope you get the chance to find out > first hand. > My main concern about acrylic was that anyone can > build there own > either buy cutting with a table saw and router or > having a plastics supply > house cut it for you. This stuff is easy to cut and > you can buy special blades > from Forest (10" $200, Ouch). I'm assuming that > Chris's brother is willing > to machine the subchassis, mayby I'm wrong here. If > my assumption is correct > then its a waste to machine plastics for a > subchassis using CNC. If we did then we'll have > missed the opportunity to find out which design > works better for our system. > I sure can't cut SS or AL with a tablesaw. If my > assumption is incorrect > then there is not much more to say on it. > As to stamped SS, most of the TT I'm thinking of > have machined SS componets. > > Stan > > > > > > http://www4.50megs.com/turntable/tg.htm > > > At 10:19 PM 3/13/2000 -0800, Igor Kuznetsoff wrote: > >Stan, > > TAS featured it on their cover of issue 121 > >(Dec.'99/Jan. '00) & called it their "first 5-Star > >Component". There is a short writeup by HP. I > >suppose they must have also have done a > >full review of it in another issue, but I don't > know > >which as I don't have a regular subscription. > There > >is mention of the Souther's being an "improved" > >version. There is a possibility that I may hear > it, > >in HP's own listening room. If that happens, I'll > let > >you know what I thought, but don't hold your > breath, > >it may never happen. > > I don't plan to use an acrylic chassis. I > only > >used the Clearaudio as an example (plus I happened > to > >have a picture handy, and it's pretty). > > I don't see how you figure that acrylic can be > >produced more cheaply than SS, which can be stamped > >out in high production, when acrylic needs hand > >finishing on every piece. But, then, I don't > figure > >that price itself is the determining factor in > making > >things sound good. It only limits the use of > >expensive materials that *could* sound good. Cost > >doesn't make "high ground", just "high price". > > > > Igor > > > >--- Stanley Goudge wrote: > >> Igor, > >> I was wondering what it would take to get a > peek > >> at your hand. Yea I like looks of the Clearaudio, > >> but never heard any reviews or anything at all. > >> Guess I'll have to call my buddy in Chicago and > go > >> to the CES this year. > >> Unlike mountains which heights never change, in > >> audio its an every day affair. > >> I still got my old Souther arm, but like the ET > One > >> much better, so if tonearms are any > >> indication of the "highest ground" then were on > the > >> wrong mountain. > >> I well give the Souther desgin credit for having > >> incredible air and transparency, but lacked > >> low end. Maybe it didn't work well with Alpha one > >> cartridge but never tried anything else. > >> > >> Fact is, acrylic designs can be mass produced > >> cheaper than SS. So your augment here is > pointless. > >> Unless of corse if acrylic designs are superior > then > >> all TT would be made this way(cheaper and > better). > >> Now, where is the high ground? > >> > >> Stan > >> > >> P.S. Anyone going to CES this year? > >> http://www3.50megs.com/engchye/turntable.htm > >> > >> > >> At 08:14 AM 3/13/2000 -0800, Igor Kuznetsoff > wrote: > >> >Stan, > >> > While the use of the isodamp does seem to > be > >> an > >> >excellent idea for use on the platter, as well > as > >> for > >> >correcting the ringing of metals as much as is > >> >possible, it might be interesting to take a look > at > >> >that "highest ground" which, if (always) > arguably > >> >appears to presently be held by the Clearaudio > TT, > >> >picture attached below. No metal anywhere in > the > >> >chassis structure. It could well be that SS & > Al > >> are > >> >materials of (medium to) *mass production* > choice. > >> > > >> > Igor > >> > > >> >--- Stanley Goudge wrote: > >> >> Alvin, > >> >> The isodamp thing started with someone > giving > >> us > >> >> the idea the platter needs to be > >> >> damped, so I suggested the Well Tempered > approach > >> by > >> >> using isodamp at the bottom > >> >> of the platter. From there we figured it can > and > >> >> will be used in some subchassis and armboard > >> >> designs. At this point its every man for > himself > >> in > >> >> regards to this area. My plea for the use > >> >> of SS in CLD has caused concerns in the lossy > >> camp, > >> >> however this was not my intensions, > >> >> only to inject another idea, one that cannot > be > >> >> executed by table saw or router as is the case > >> with > >> >> most lossy designs. BTW most TT designers > begin > >> with > >> >> a lossy design only to upgrade or > >> >> redesign using more rigid materials, SS or > >> aluminum > >> >> seem to be materials of choice, not only > >> >> for TT but tonearms as well. The lossy route > is > >> well > >> >> travelled and I believe their are better > >> >> routes which will lead us to much higher > ground. > >> >> > >> >> Stan > >> >> > >> >> > >> >> > >> >> > >> >> At 03:15 PM 3/12/2000 -0500, Alvin Richardson > >> wrote: > >> >> >Gents, > >> >> >I am relatively new to the digest, and I try > to > >> >> keep up with what is going > >> >> >on, although with too many different forums > >> going > >> >> on at once, it is > >> >> >difficult to know what is being done. In this > >> >> instance it would appear that > >> >> >this purchase is being made apart from the > >> general > >> >> consensus. My question > >> >> >is, how is this contributing to the making of > >> the > >> >> teres? I am assuming that > === message truncated === __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: Re: [teres] isodamp Date: Tue, 14 Mar 2000 12:20:27 -0700 From: Stanley Goudge, Stanley Goudge To: teres@aiko.com; teres@aiko.com Igor, Check out the link to the best TT gallery I've seen. If you haven't seen this one, man your in for a treat. Stan http://www4.50megs.com/turntable/tg.htm At 09:17 AM 3/14/2000 -0800, Igor Kuznetsoff wrote: >Hi, Stan, > I'm not familiar with the SPJ, but, well, >women do generally have better hearing than men, and >more women are showing up in engineering nowadays. >The combination could result in an interesting new >perspective. I just hope it doesn't come in "Peach". >Where can I get a look at it? > > As to the Sota, well, it puts me, anyway, >right where I've been all along on the rigid+lossy >issue: it is precisely my philosophy, and has been for >at least 10 years. I believe that both can be had, >without the additional ringing of metal. (I don't >know anything about the new Sota). Funny you should >mention it just now, because I have a rough draft of a >note on just that very thing, which I wrote last >night, but was too tired to clean up for sending . >Will try to sometime by tonight. > > Igor > >--- Stanley Goudge wrote: >> Igor, >> I'm sure the Clearaudio is world class, sure >> looks it anyway. >> How about that Spj la luce TT, looks cool, but >> owning a TT designed >> by a women....well I don't know. BTW I heard rumors >> from Sota that HP's new >> reference is the SOTA millennium and a review is in >> the works. Not >> sure where this puts us, as I think the Sota >> combines rigidity and lossy >> componets. I hope you get the chance to find out >> first hand. >> My main concern about acrylic was that anyone can >> build there own >> either buy cutting with a table saw and router or >> having a plastics supply >> house cut it for you. This stuff is easy to cut and >> you can buy special blades >> from Forest (10" $200, Ouch). I'm assuming that >> Chris's brother is willing >> to machine the subchassis, mayby I'm wrong here. If >> my assumption is correct >> then its a waste to machine plastics for a >> subchassis using CNC. If we did then we'll have >> missed the opportunity to find out which design >> works better for our system. >> I sure can't cut SS or AL with a tablesaw. If my >> assumption is incorrect >> then there is not much more to say on it. >> As to stamped SS, most of the TT I'm thinking of >> have machined SS componets. >> >> Stan >> >> >> >> >> >> http://www4.50megs.com/turntable/tg.htm >> >> >> At 10:19 PM 3/13/2000 -0800, Igor Kuznetsoff wrote: >> >Stan, >> > TAS featured it on their cover of issue 121 >> >(Dec.'99/Jan. '00) & called it their "first 5-Star >> >Component". There is a short writeup by HP. I >> >suppose they must have also have done a >> >full review of it in another issue, but I don't >> know >> >which as I don't have a regular subscription. >> There >> >is mention of the Souther's being an "improved" >> >version. There is a possibility that I may hear >> it, >> >in HP's own listening room. If that happens, I'll >> let >> >you know what I thought, but don't hold your >> breath, >> >it may never happen. >> > I don't plan to use an acrylic chassis. I >> only >> >used the Clearaudio as an example (plus I happened >> to >> >have a picture handy, and it's pretty). >> > I don't see how you figure that acrylic can be >> >produced more cheaply than SS, which can be stamped >> >out in high production, when acrylic needs hand >> >finishing on every piece. But, then, I don't >> figure >> >that price itself is the determining factor in >> making >> >things sound good. It only limits the use of >> >expensive materials that *could* sound good. Cost >> >doesn't make "high ground", just "high price". >> > >> > Igor >> > >> >--- Stanley Goudge wrote: >> >> Igor, >> >> I was wondering what it would take to get a >> peek >> >> at your hand. Yea I like looks of the Clearaudio, >> >> but never heard any reviews or anything at all. >> >> Guess I'll have to call my buddy in Chicago and >> go >> >> to the CES this year. >> >> Unlike mountains which heights never change, in >> >> audio its an every day affair. >> >> I still got my old Souther arm, but like the ET >> One >> >> much better, so if tonearms are any >> >> indication of the "highest ground" then were on >> the >> >> wrong mountain. >> >> I well give the Souther desgin credit for having >> >> incredible air and transparency, but lacked >> >> low end. Maybe it didn't work well with Alpha one >> >> cartridge but never tried anything else. >> >> >> >> Fact is, acrylic designs can be mass produced >> >> cheaper than SS. So your augment here is >> pointless. >> >> Unless of corse if acrylic designs are superior >> then >> >> all TT would be made this way(cheaper and >> better). >> >> Now, where is the high ground? >> >> >> >> Stan >> >> >> >> P.S. Anyone going to CES this year? >> >> http://www3.50megs.com/engchye/turntable.htm >> >> >> >> >> >> At 08:14 AM 3/13/2000 -0800, Igor Kuznetsoff >> wrote: >> >> >Stan, >> >> > While the use of the isodamp does seem to >> be >> >> an >> >> >excellent idea for use on the platter, as well >> as >> >> for >> >> >correcting the ringing of metals as much as is >> >> >possible, it might be interesting to take a look >> at >> >> >that "highest ground" which, if (always) >> arguably >> >> >appears to presently be held by the Clearaudio >> TT, >> >> >picture attached below. No metal anywhere in >> the >> >> >chassis structure. It could well be that SS & >> Al >> >> are >> >> >materials of (medium to) *mass production* >> choice. >> >> > >> >> > Igor >> >> > >> >> >--- Stanley Goudge wrote: >> >> >> Alvin, >> >> >> The isodamp thing started with someone >> giving >> >> us >> >> >> the idea the platter needs to be >> >> >> damped, so I suggested the Well Tempered >> approach >> >> by >> >> >> using isodamp at the bottom >> >> >> of the platter. From there we figured it can >> and >> >> >> will be used in some subchassis and armboard >> >> >> designs. At this point its every man for >> himself >> >> in >> >> >> regards to this area. My plea for the use >> >> >> of SS in CLD has caused concerns in the lossy >> >> camp, >> >> >> however this was not my intensions, >> >> >> only to inject another idea, one that cannot >> be >> >> >> executed by table saw or router as is the case >> >> with >> >> >> most lossy designs. BTW most TT designers >> begin >> >> with >> >> >> a lossy design only to upgrade or >> >> >> redesign using more rigid materials, SS or >> >> aluminum >> >> >> seem to be materials of choice, not only >> >> >> for TT but tonearms as well. The lossy route >> is >> >> well >> >> >> travelled and I believe their are better >> >> >> routes which will lead us to much higher >> ground. >> >> >> >> >> >> Stan >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> At 03:15 PM 3/12/2000 -0500, Alvin Richardson >> >> wrote: >> >> >> >Gents, >> >> >> >I am relatively new to the digest, and I try >> to >> >> >> keep up with what is going >> >> >> >on, although with too many different forums >> >> going >> >> >> on at once, it is >> >> >> >difficult to know what is being done. In this >> >> >> instance it would appear that >> >> >> >this purchase is being made apart from the >> >> general >> >> >> consensus. My question >> >> >> >is, how is this contributing to the making of >> >> the >> >> >> teres? I am assuming that >> >=== message truncated === >__________________________________________________ >Do You Yahoo!? >Talk to your friends online with Yahoo! Messenger. >http://im.yahoo.com > Subject: RE: [teres] isodamp; lossy approach is not the best? Date: Tue, 14 Mar 2000 14:03:54 -0700 From: Jon Lane, Jon Lane To: Teres@Aiko.Com Thanks for your kind reply, Doug. Be advised you're not alone...I'm actually moving away from my original plans for a very massive air design by way of the Teres timing. No way I could resist the value Chris (and others) presented. So, conventional bearing it is, and with it, the improvement in coupling. Further, while the "rigid is better" camp is fairly well understood and represented, I also plan to go to mass extremes with my solid alum chassis. I'm only following my own advice as far as the rigid/mechanical coupling thing is concerned while the rest of me is/was headed off into mass, damping, and even air bearings. Ain't DIY fun? JL > Jon, > Very interesting analysis. The slightly odd > thing is that I agree with > your fundamental idea, but my current project > (see my intro message > preceeding this) is taking me somewhat away from > this. When I was > planning on using a conventional bearing, I was > incorporating measures > to try to directly couple the bearing and the > tonearm as much as > possible. As a friend who ran the hi-fi shop > when I was in college said > 'make sure nothing moves, but if it does, make > absolutely sure > everything moves together'. Somehow, though, I > don't think I completely > made the connection that an air-bearing will > undermine this. This > criticism has been leveled at air-bearing arms > before (any compliance is > too much compliance), but I hadn't run into it on > a platter before. > > I'll have to do some thinking. Part of me thinks > that if I get to the > point that the compliance of the air-bearing is > what's causing my > problems then I'm doing pretty well, but you've > planted a seed of doubt. > > Doug. Subject: RE: [teres] isodamp; lossy approach is not the best? Date: Tue, 14 Mar 2000 14:25:56 -0700 From: Jon Lane, Jon Lane To: teres@aiko.com > A much quieter background would be achieved if "no > energy appeared anyplace", except, of course, at the > cartridge, the only place where it actually belongs. > > Igor The rigid loop school believes that if all parts of the system are brought into perfect coupling, then all "noise" will effectively cancel. Equivalent to a pair of out-of-phase speakers with the same precise motion: No output. With a 'table, the only thing left should be cantilever motion. Energy *will* appear within the loop - either internally generated as with the cart, or externally generated as with acoustic feedback or motor racket. Regarding internal noise, make it as easy as possible to sink/couple (the whole premise behind a plastic platter under a plastic record) thus attenuating it through mass while ensuring that all bits "move" or bend in unison. Actually, if this could magically be made perfect, I'd venture the blackness would grow darker. *External* input, OTOH, demands a variety of real-world solutions from siting the table elsewhere, adding the infamous catbox, or turning off the lousy Velodyne. Again, lowering the input from outside the system also aids sonic blackness, possibly explaining the Maplenol and SOTA's subjective sound. They are either decoupled entirely or cannot be modulated in the first place. I think it's the noise from outside that modulates the workings of lighter 'tables, potentially raising their noise floor. The Linn has very good - but maybe not great - mechanical transmission of energy away from stylus, assuming a very good arm, and I think sounds more correct in terms of low-level information and the precision of its sonic image placement. Obviously, all of this is conjecture. I'll attempt an equally ham-fisted reply to another such post later tonight. The point of all of this is to understand, so please, have at these notions with enthusiasm... Jon Lane Subject: Re: [teres] isodamp; lossy approach is not the best? Date: Tue, 14 Mar 2000 16:58:26 -0700 From: Thom Mackris, Thom Mackris To: teres@aiko.com Oops! Sorry about the last post which contained only quoted text... duh! What I meant to say relates to Jon's comments about the energy loop between arm, chassis, and bearing. The way I see it, thing's are going to "rattle" on a microscopic level no matter what you do, and you're best off if everything rattles in the same direction at the same time. This would minimize relative movement between the main bearing and the tonearm bearing. This is essentially a rehash of my argument for not having a separate tonearm pod. Obviously, this "rattling" is going to throw the mass at the business end of the arm to and fro, and damping these bad vibes would serve the best interest of any design you arrive at. It all comes down to prioritization and compromise. Reducing this rattling would seem to me to stand higher up the food chain than would damping. Rigid as possible first, damp later. It seems to me as if this is one case where one can have their cake and eat it. I can't believe that it's impossible to damp such a rigid surface as Jon proposes, either via a constrained layer or through some sort of gooey stuff. Thom __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com Subject: RE: [teres] isodamp; lossy approach is not the best? Date: Tue, 14 Mar 2000 17:53:23 -0700 From: Schei, Kenneth, Schei, Kenneth To: 'teres@aiko.com' Thom: I like your concept of everything rattling in the same direction at the same time. Theoretically that's the best solution and it can be employed effectively at many levels. The concern I have is that at the micro level that we're talking about (stylus movement), only a very tiny amount of differential movement changes the rattles from being in phase and thus moving with each other, to being out of phase and thus multiplying their effect upon each other. I find it easier to believe that we can effectively sink all of the rattles and keep them from interacting each other that way. Ken Ken Schei, P.E. Project Engineer Antarctic Support Associates Email address: scheike@asa.org Phone: 303-643-0163 > -----Original Message----- > From: Thom Mackris [SMTP:thom_mackris@yahoo.com] > Sent: Tuesday, March 14, 2000 3:54 PM > To: teres@aiko.com > Subject: Re: [teres] isodamp; lossy approach is not the best? > > Oops! Sorry about the last post which contained only quoted text... duh! > > What I meant to say relates to Jon's comments about the energy loop > between > arm, chassis, and bearing. The way I see it, thing's are going to > "rattle" > on a microscopic level no matter what you do, and you're best off if > everything rattles in the same direction at the same time. This would > minimize relative movement between the main bearing and the tonearm > bearing. > This is essentially a rehash of my argument for not having a separate > tonearm pod. > > Obviously, this "rattling" is going to throw the mass at the business end > of > the arm to and fro, and damping these bad vibes would serve the best > interest of any design you arrive at. > > It all comes down to prioritization and compromise. Reducing this > rattling > would seem to me to stand higher up the food chain than would damping. > Rigid as possible first, damp later. > > It seems to me as if this is one case where one can have their cake and > eat > it. I can't believe that it's impossible to damp such a rigid surface as > Jon proposes, either via a constrained layer or through some sort of gooey > stuff. > > Thom > > > __________________________________________________ > Do You Yahoo!? > Talk to your friends online with Yahoo! Messenger. > http://im.yahoo.com Subject: Re: [teres] Hello Date: Tue, 14 Mar 2000 20:48:57 -0700 From: Nicholas McKinney, Nicholas McKinney To: teres@aiko.com At 03:51 PM 3/7/00 -0700, phclark wrote: >It's kind of hard to know who I'm replying to at times. Anyway, this looks >interesting. Please keep us apprised of movement/progress. > >THX. > >Peter C Hi Peter, it was me (Nick) It seems that the base could be made easily enough this way once the plans were laid out. Especially in a MDF piece first as a test piece. What are the current status of the base designs? I had to unsubscribe for the last week since I was out of town so I might have lost quite a bit of Teres email since this original post. Nick >-----Original Message----- >From: Jeremy Epstein >To: teres@aiko.com ; nick@lambdacoustics.com > >Date: Tuesday, March 07, 2000 2:48 PM >Subject: Re: [teres] Hello > > >>Nicholas McKinney wrote: >>> >>> Hi Folks, >> >> >>Hi Nick! >> >> >>> And finally, my partner is a serious wood junkie, so much so one day he >came >>> home with a large -CNC- 3 axis router. Well things have gone now to >include a >>> vacuum hold down system, etc for this monster. >>> >>> Well to make a long story short, I can get him to make bases if you guys >>> wanted. He has alot of experience with exotic stuff like butcher block, >>> Diamond wood, Corian, etc. Since he will make my base, the setup cost is >>> already taken care of for anyone else that wanted one. Also, if Corian >was >>> chosen, my neighbor (shop) uses -alot- of this (palettes) and we can >probably >>> get some better pricing than what many cabinet makers would charge. The >>> problem I see is that black (Dupont Nocturne) is what I want, and not >many >>> bathrooms around here get that color.................. >> >>I'd be interested in piggy backing on this if you are going to do it. >> >>> Have you guys discussed making dual matching "flat bases" and having a >recess >>> made into each one for a bicycle tube like a sandwich? >> >>Clever. >> >>-j >> >>-- >>========================================= >>Jeremy Epstein .........jepstein@shwd.com >>========================================= >> Subject: RE: [teres] isodamp; lossy approach is not the best? Date: Tue, 14 Mar 2000 20:59:50 -0700 From: Jon Lane, Jon Lane To: teres@aiko.com Ken said: > I've read your theses carefully, but I struggle > with the statement "ability > for all energy to appear at all places." That > statement appears to violate > the basic laws of physics as I understand them, > and thus reduces the > effectiveness of your argument in my mind. I don't mean to suggest that what's going on is a trendy, audiophile violation of physics - quite the opposite but without the formal definitions, I'd hoped. Once again just to be sure, my stuff is just me thinking out loud and my experiential basis is still lacking absolute verification - much of this is street-level theory co-mingled with equal parts instinct and empirical results. Obviously, we could use some finer analysis. However, I'll take another shot at it since I brought it up. Concerning chassis, I think I see it this way. We have four choices: 1. Rigid, conductive chassis; 2. Rigid, non-conductive chassis; 3. Compliant, conductive chassis, and; 4. Compliant, non-conductive chassis. These are relative terms, please bear with me... 1. We select the most rigid, most "vibrationally conductive" material we can find (aluminum comes to mind), thus ensuring that - just like the plastic platter/plastic record Teres design - we provide a low-impedance path for any energy transmitted down the armtube to dissipate into the chassis. Essentially, the "mechanical diode" - once it leaves the arm, it ain't getting back in there (and I agree 100% with my understanding of Igor's point - pointed feet aren't diodes, despite their shape). Any impedance mismatch whatsoever at the arm/chassis junction reduces the ability of the relatively uncontrolled arm to deal with the ferocious HF content cut into the RIAA eq curve. (Ever notice how much cry cheap headshells give off?) Again, the platter is doing it's job with regard to energy exiting in *that* direction, we need to turn our attention to the only other path for energy leaving the stylus: the arm, most of them being rigid, alloy affairs with fixed bearings. Turning next to chassis rigidity, we next use a lot of material, aiding it dramatically. We should find that of service in ensuring that no compliance occurs between the moving parts, which, I'm thinking, aids fundamentals, especially in the lowest octaves. (Motion is only by way of compliance between arm and platter, thus describing an entirely new, but lower set of problem frequencies. Our concept #1 prohibits this occurring.) Last, we damp the whole affair to taste, having thus ensured both HF sinking/attenuation and LF stability. 2. We select a rigid chassis, but with impaired impedance matching. Say, a block of ceramic or stone. All of the above remain in place regarding a intimate connection between parts, but this time with HF sinking worsening with increasing frequency. We reflect increasingly more energy back up the arm base and into the tube as we increase frequency, not a very good thing given the RIAA curve. Low frequency fundamentals remain strong, but HF hash appears at the playing end of the machine that wasn't there before. 3. Next, we make basically a thin version of #1. A good mechanical match once again which aids the HF losses. Maybe a plate metal chassis. Our HF match and sinking returns somewhat, but isn't as effective for reasons of limited volume to attenuate the energy as well. Things presumably get even worse when we lose our ability to rigidly constrain the parts and we find new reactances in the lower ranges. All in all, we've saved mass and money, but kept only some of the benefits of allowing the arm to "talk" to the chassis. Plus, we've developed a loss of mechanical integrity creating a reactance somewhere in the lower octaves. 4. Finally, we make a design both compliant and poorly matched. We lose all of the previous benefits. This is partially the fear I have in using a material or materials with a strong fundamental internal mode at a lower frequency unable to be corrected by any means. With a sandwich of wood and lead, you lose both energy coupling to the arm, as well as risking severe suseptance to external influences, the frequencies below 1kHz being far more powerful and difficult to stop in typical listening systems. Depending on the mass of this structure, we are creating a reservoir for energy to bounce around it at frequencies low enough we cannot control them. It seems we've learned that we want to ensure a good impedance match between arm and chassis. We've speculated further that a rigid loop aids the bass for reasons apparently related to ensuring zero motion between the parts and rejection of external input. I don't know the precise reason why, but I've found that such designs do have a better bottom. Now, things get complex again when we consider that any of the above can be built either as lightweights or as heavyweights. The tonearm "sinking" changes once again, presumably in favor of the heavy designs, and rigidity is inherently connected to the amount of any given material, again with the benefit going to the heavier design. The only downside is that we lower the fundamental resonance although we don't increase internal suseptance to the outside input while doing so. The only remaining thing, as I see it, is to critically damp any energy in the system put there by internal influences like the cartridge. I have suggested performing this task after the machine is built and able to be tested, and I'd planned to observe the behavior of energy applied by a transducer to the arm location at various points across the surface of the chassis. While fairly crude, it seems to me that using a scope and pickup, one could progressively damp the surfaces until the best compromise between acceptance and rejection across the frequencies in question came about. Anyone? > Other points of your thesis > also seem alien to me. You want a lossless > mechanical loop; in my mind that > would return energy sunk into it back to the > stylus, only delayed as it > travels through the loop. > I can't help but think > of that process as delayed > feedback, which is loved by the transistor crowd > but has no place in my > life. > That delayed feedback is probably why > Linns and Oracles don't have > the "blackness" of a SOTA or Maplenoll, as you > point out. I understand your point, but if the assembly is critically damped, this energy reappears only "once", at a greatly attenuated level, and is attenuated rapidly after that. This first appearance is far, far less destructive however, than leaving it in the arm, which is the risk of not sinking it at all. > Correct me if I'm > wrong, but I suspect that the resultant sound of > a "bright" base would be > brighter than that of a "lossy" system. Actually, if this theory holds, the reverse may be true... Tables I've made even with no damping of conductive chassis have far better resolution through draining the excess noise away from the cart, although they generally ended up benefiting from progressive damping as we dialed them in. The thing I think we need to keep in mind is the extreme susceptibility of undamped conductive chassis to *external* input. Frankly, an entire post could/should be written attempting to qualify this effect as well. Personally, I prefer to see this is a separate problem and limit my efforts to dealing with only the energy within the loop. But then if you listen at levels above 90dB with the table close to the speakers... > One has > to listen to decide if > brighter is better. I remain allied to a > "massive, lossy base," as Grant > aptly described it. Bright only if you don't damp properly. The heavy lossy base has been seen to reject input in the first place thus throwing away the benefits of sinking unwanted energy away from far more delicate parts like bearings, armtubes, and cartridges. > As an amateur speaker designer, I don't > understand how you equate an > undersize speaker boss to a lossy TT base. An > undersize speaker boss has a > high Q and requires more damping, just the > opposite of a lossy base. As you > say, the analogy is indeed inverted, but I'm > unable to set it aright. An undersized box is underdamped, and cannot be brought to a state of Q=0.5, or critical damping. A large box can; throw some bricks in there [rolls eyes - this analogy sucks] to decrease its internal volume to bring it from say, Q=0.4 to Q=0.5. Likewise, undamped energy left in the arm cannot be brought into a state of critical damping without first allowing it to dissipate as freely as possible. Once having done so (and with its relative level conveniently diminished), you can commence to critically damp it. The small box is discarded just as the low-admittance chassis would be - there is no fix. OTOH, the larger box can easily be partially filled in order to raise it's Q. A very clumsy analogy, but it worked for me... > I view our dissimilar philosophies as very > constructive, especially in this > format. I do too. Looking forward to further comment and enlightenment. > Each of us will ultimately construct our > TT bases according to our > beliefs and tastes, and we can profit by the > ideas of others in doing so. I > only hope I have the opportunity to hear the > results of different designs. You're always welcome. Jon Lane Subject: Re: [teres] Hello Date: Tue, 14 Mar 2000 23:51:21 -0700 From: Steve Zettel, Steve Zettel To: teres@aiko.com Hi, Nick > Hi Al, well alot like this picture I would imagine; > > http://www.audioadvancements.com/amazon1.htm I like the looks of the that. > > I plan to make a recess in each flat panel sized perfectly for a tube shaped > air bladder, then leave about 0.1~0.2" of space between them when inflated. Would you be doing the recesses via CNC machining too? How difficult would it be to delete this part of the process? I was thinking of resting the whole works on top of a sandbox, and the sandbox on the air bladders. > The motor would be on the bottom panel and pass through an access hole on the > upper. > > In my case the motor on the lower panel would be replaced by an "idler > bearing" > and the motor moved outboard. This idler bearing would have a dual groove > pulley, one groove carrys the belt for the platter, and the other groove > carries another belt to the motor. This should "theoretically" lower the > motor > vibrations and speed changes to the platter. I am one of the people Thom mentioned that wants to avoid this complexity. 8^) > > Here is a picture of the CNC machine cutting a speaker baffle before we got > the > vacuum hold down; > > http://www.lambdacoustics.com/images/baffles/baffle1.jpg > > http://www.lambdacoustics.com/images/baffles/baffle2.jpg > > I say we because my speaker cabinets take up all of his time pretty much. I > seem to live over there now ;-/ Now those are what I would call "solid" speaker panels! Thanks, Nick.