American Sound, "The Absolute Nothing"

[christensenleif@msn.com]

Some claim a mechanical anchoring of the spindle/platter is better than an air bearing
One of them I believe is Tommy Hørning

 

[PeterA]

That's why you need high air pressure on the axial bearing to absorb lateral forces, e.g. belt tension, so that the spindle doesn't lean against the bearing surface when the platter rotates. I wouldn't build anything with air bearings these days, there are bearings that don't need lubrication anymore, e.g. CMB (Clearaudio) or S Grün from TW Acustic. If a bearing doesn't need lubrication, you can be sure that the friction is very low.

You could get some indication of how low that bearing friction is by hand spinning the platter to 33 RPM and seeing how long it takes to stop.

 

[DasguteOhr]

The main advantage with a air bearing is the possibility to use a very heavy platter, without much friction. The disadvantages are need of air supply and the potential noise, with some industrial bearings you need very high pressure and very clean air.

Its ok when it works for you and you are happy with it.
there are other good solutions, tungsten carbide bearing max load 600lbs. with 40lbs flywhell 800rpm and 110lbs platter. the best sounding turntable i ever heard in my life. stability in tones is unsurpassed. e.g. piano.

Next year i get it i hope so.

 

[Lagonda]

Its ok when it works for you and you are happy with it.
there are other good solutions, tungsten carbide bearing max load 600lbs. with 40lbs flywhell 800rpm and 110lbs platter. the best sounding turntable i ever heard in my life. stability in tones is unsurpassed. e.g. piano.View attachment 136296

Next year i get it i hope so.

Are you waiting for someone to die and leave it to you in his testament ? Very interesting belt setup, what motor does it use ? Love the loose transformer on the floor, better lock up your kids, dogs and cats !

 

[Mike Lavigne]

Some claim a mechanical anchoring of the spindle/platter is better than an air bearing.

i enjoy having both in my system. visitors many times have a preference. both ways. of course, there are many variables besides the bearing type too, so it's not any truly scientific compare. but presentation can be right both ways.

one tt having both an air float for the platter and an air bearing for the arm i think makes the differences more pronounced and easier to grasp.

 

[DasguteOhr]

Are you waiting for someone to die and leave it to you in his testament ? Very interesting belt setup, what motor does it use ?

No, he gave up the hobby. Sold it to my cousin three years ago. I'm building him a nice tube amplifier in exchange. Revox A77 motor, belt rubberized Kevlar tape. With capstan shafts almost 100% wrap angle on the platter for perfect power transmission.

P.S
the upper part of the platter is noise protection glass no contact with the spindle of bearing

 

[Maril555]

Thanks for the explanation, but I highly doubt that any turntable uses a full air bearing where the platter is in contact with nothing but an air cushion. I’m almost certain of this because I haven’t seen any concrete proof, just vague explanations from manufacturers that seem evasive. Since full air bearings are industrially available, I don’t believe it’s a patent or company secret issue, but rather a challenge of implementation. I suspect there is a sleeve bearing or something similar to prevent lateral movement caused by the belt, motor, or occasional contact with the platter while changing records. Additionally, there must be some kind of thrust bearing to maintain the air gap between the platter and plinth when placing a record, using a heavy stabilizer, dealing with changes in air pressure, or when the platter is accidentally bumped.

I think after Peter A. emphasized multiple times that there is ZERO physical contact b/w the platter and the plinth that should be sufficient to stop the argument.
In discussing the issue with David himself, it is my impression of the design as well. Granted I’m not as familiar with the details of it as Peter is.
The explanations of the design are “vague and evasive” on purpose, since it’s proprietary and David doesn’t want to divulge it.
And I don’t think he is under any obligations to provide a proof of the concept.

 

[mtemur]

I think after Peter A. emphasized multiple times that there is ZERO physical contact b/w the platter and the plinth that should be sufficient to stop the argument.

He clearly said that he doesn't know exactly how it is.

The explanations of the design are “vague and evasive” on purpose, since it’s proprietary and David doesn’t want to divulge it.

Really?

 

[mtemur]

And I don’t think he is under any obligations to provide a proof of the concept.

This argument, especially my posts are not only about American Sound turntables. It is about the concept of air bearing.

 

[andromedaaudio]

Bollox !!!

I think you should change your avatar to ' Erebus "

 

[PeterA]

one tt having both an air float for the platter and an air bearing for the arm i think makes the differences more pronounced and easier to grasp.

I think that actually confuses the issue by adding an extra variable. I would seek out the preferred approach for each component and then listen in combination to pass judgment. Sometimes the design is integrated so it is more difficult to separate.

 

[PeterA]

I think after Peter A. emphasized multiple times that there is ZERO physical contact b/w the platter and the plinth that should be sufficient to stop the argument.
In discussing the issue with David himself, it is my impression of the design as well. Granted I’m not as familiar with the details of it as Peter is.
The explanations of the design are “vague and evasive” on purpose, since it’s proprietary and David doesn’t want to divulge it.
And I don’t think he is under any obligations to provide a proof of the concept.

Thank you very much. Everything you write in your post is completely correct but it will do little if anything to tamper down the rampant speculation and arguments.

 

[PeterA]

He clearly said that he doesn't know exactly how it is.


Really?

I did not understand the design until I owned it and started taking apart these turntables. It’s very clever and very simple and I now understand it.

Yes, really. This bearing is unique to the American sound turntables and David does not want to discuss it. It is quite reasonable from the designer’s point of view.

 

[Mike Lavigne]

I think that actually confuses the issue by adding an extra variable. I would seek out the preferred approach for each component and then listen in combination to pass judgment. Sometimes the design is integrated so it is more difficult to separate.

Peter,

no, it clarifies the nature of the beast. what does it do for the music. and the experience.

my point was that as i live with, and have lived with, multiple turntables and drive types, and bearing types, along with multiple arm types and arm bearing types, with all sorts of cartridges......lived with them for years and years........BUT.......most visitors to my room have not done that. so......that having a tt and arm both using air float and air bearing allows those visitors to really hear how those features present the music. and i personally appreciate what that combo does for my listening too.

i specifically said that i'm not claiming any scientific proof, just a taste of what this does. and some listeners really like it. with a high level, well executed hard bearing tt and arm sitting next to it.

unless you live with all these variables over an extended time, the nuances are hard to determine......if they are combined. what is causing what? for the visitor. i already know.

 

[Joe Cohen]

This is from an old review when Jonathan Valin visited Audio Tekne. So, I don’t believe this is as delicate as you think. I have not tried this!

“As an added bonus, I also got to hear my LPs played back on Mr. Imai’s record-playing system, the ACP-8801 with air-bearing turntable, pivoted arm, and Audio Tekne MC-6310 phono cartridge (third picture to the left below)—a device so immune to vibration that I actually watched, in some horror (since it was one of my discs on the platter), Mr. Imai slam a heavy rubber-coated mallet onto the tonearm standard, the plinth, and—with my heart in my throat!—the record clamp while the record was playing! I heard nothing through the speakers (and these were, as you will soon find out, horn loudspeakers), save for a very-low-level “thunk.” The tonearm never skipped a beat!”

I witnessed this same demonstration at Bé Yamamura's house in Tuscany in 1993. The demo unfolded in exactly the same manner. He showed us (my future wife and I) a rubber mallet, and without saying a word proceeded to hit the graphite record weight with force while the LP was playing. The needle, as Jonathan reported from his encounter, did not skip a beat. Bé later removed the platter so we could see the cylindrical bearing with its many air holes.

 

[mtemur]

I did not understand the design until I owned it and started taking apart these turntables. It’s very clever and very simple and I now understand it.

Yes, really. This bearing is unique to the American sound turntables and David does not want to discuss it. It is quite reasonable from the designer’s point of view.

So, you're positive that American Sound turntables—yes, even the latest one—have no contact with the bearing, plinth, or anything else, except for the belt?

Reading through the response about the ‘uniqueness’ of the bearing, I couldn’t help but get the impression that as if David personally invented the air bearing turntable, and Micro Seiki just walked in and swiped the idea right from under him.

 

[Audiohertz2]

I witnessed this same demonstration at Bé Yamamura's house in Tuscany in 1993. The demo unfolded in exactly the same manner. He showed us (my future wife and I) a rubber mallet, and without saying a word proceeded to hit the graphite record weight with force while the LP was playing. The needle, as Jonathan reported from his encounter, did not skip a beat. Bé later removed the platter so we could see the cylindrical bearing with its many air holes.

Wait, what ...... !

 

[Argonaut]

I did not understand the design until I owned it and started taking apart these turntables. It’s very clever and very simple and I now understand it.

Yes, really. This bearing is unique to the American sound turntables and David does not want to discuss it. It is quite reasonable from the designer’s point of view.

Excellent …So you are perfectly placed to answer a very simple question without giving away any proprietary design details .

Is the Main platter of the AS 2000 entirely friction and contact less of any other part of the turntable , other than the drive string ? In other words , Does the platter rotate entirely in *Free Air* ???

 

[Argonaut]

I witnessed this same demonstration at Bé Yamamura's house in Tuscany in 1993. The demo unfolded in exactly the same manner. He showed us (my future wife and I) a rubber mallet, and without saying a word proceeded to hit the graphite record weight with force while the LP was playing. The needle, as Jonathan reported from his encounter, did not skip a beat. Bé later removed the platter so we could see the cylindrical bearing with its many air holes.

Heh … Extraordinarily Cool

 

[bonzo75]

I witnessed this same demonstration at Bé Yamamura's house in Tuscany in 1993. The demo unfolded in exactly the same manner. He showed us (my future wife and I) a rubber mallet, and without saying a word proceeded to hit the graphite record weight with force while the LP was playing. The needle, as Jonathan reported from his encounter, did not skip a beat. Bé later removed the platter so we could see the cylindrical bearing with its many air holes.

Be Yamamura and Imai of audio tekne were friends and lived in Italy for a long time and friends with Gian and Pietro. Gian could say more about this will ask him