I said I would never buy another Turntable...Argh !!!

[ddk]

I own one of the last Barco CRT projectors, certainly there are only one or two in the UK.
Some parts are unobtanium, and there is only one tech here who can fix it.
I'm keeping my fingers crossed it doesn't break down.
I do hope these one of a kind AS-2000 motors are able to be sorted if they fault.

Motor controller was designed to be field serviceable and has only 5 major components, all mil-spec and industrial components nothing proprietary. The motor is the best professional one that Papst made and like EMT's motors designed to function 24/7 maintenance & problem free in a work environment for decades and in case of something catastrophic, fire, earthquake, bombs, etc. I have quite a few more as backup.

david

 

[853guy]

Motor controller was designed to be field serviceable and has only 5 major components, all mil-spec and industrial components nothing proprietary. The motor is the best professional one that Papst made and like EMT's motors designed to function 24/7 maintenance & problem free in a work environment for decades and in case of something catastrophic, fire, earthquake, bombs, etc. I have quite a few more as backup.

david

Hello ddk,

The Pabsts have a well-deserved reputation. I believe the Rek-O-Kut, Thorens, Carson, BEG, Fairchild and Empire tables used various ones (I think Voyd used them too?), and Win Tannon’s Sakia uses one. Like any motor, they’re only as good as the controller, requiring three phase for best results - the Pabsts found in various European tape machines tend to be fed from single phase power supplies, as far as I’m aware.

Just so you know, of all the stuff on interweb at the moment, this is my favourite thread.

Thanks again for being so forthcoming on info. For those of us not likely to be among the six to own an AS-2000, the details are a welcome consolation.

Best,

853guy

 

[Stacore]

Motor controller was designed to be field serviceable and has only 5 major components, all mil-spec and industrial components nothing proprietary. The motor is the best professional one that Papst made and like EMT's motors designed to function 24/7 maintenance & problem free in a work environment for decades and in case of something catastrophic, fire, earthquake, bombs, etc. I have quite a few more as backup.

david

Although I have only the little brother, even the EMT930 motor is sth to admire. I'm trying to find time to assemble my own 3-phace uC based controller with a linear, rather than class D, 3-channel amplifier to give the motor the best and cleanest operating conditions.
Your comments on the role of the controller are very encouraging.

Cheers,

 

[rockitman]

I'm leaning towards having Herzan build me a rigid 2" steel box tube welded stand like they have in the past for me and use the AS for awhile on the rigid table w/o any active isolation devices. At some point I will seek to demo the AVI series active isolation beams under the TT. I feel it may be too risky to buy Herzan's active isolation work station table first and committing to active isolation in the event for some unforeseen reason the TT sounds better w/o active isolation.

What are your thoughts Mike L ?

I am planning to take earlier delivery ....Dec/Jan versus the original March/Early April timeframe.

 

[ddk]

Although I have only the little brother, even the EMT930 motor is sth to admire. I'm trying to find time to assemble my own 3-phace uC based controller with a linear, rather than class D, 3-channel amplifier to give the motor the best and cleanest operating conditions.
Your comments on the role of the controller are very encouraging.

Cheers,

Hi Jarek,

That's exactly the design of this controller! The EMT motors 927/930 are the same quality and built to survive any amount of abuse under very conditions, very special. I tried running my 927 free spinning as you suggest but went back to the mechanical brake, I lost something in the sound without it. What improved the sound was using very low viscosity high grade instrument oil instead of what's normally suggested.

david

 

[spiritofmusic]

Dave, I've sent you a PM.
Do drop me a line when you get the time.
Much obliged.
I'm v pleased to know my direct rim drive w no servo and no feedback loop is a good call by the designer.
There are a couple of uber high end designs that I love the look of, Saskia 2 Ref idler and The Disc Rotator belt drive, that could form the basis of a final shortlist of a final final tt upgrade, unfortunately AS-2000 won't be on it .

 

[microstrip]

Hello ddk,

The Pabsts have a well-deserved reputation. I believe the Rek-O-Kut, Thorens, Carson, BEG, Fairchild and Empire tables used various ones (I think Voyd used them too?), and Win Tannon’s Sakia uses one. Like any motor, they’re only as good as the controller, requiring three phase for best results - the Pabsts found in various European tape machines tend to be fed from single phase power supplies, as far as I’m aware.

Just so you know, of all the stuff on interweb at the moment, this is my favourite thread.

Thanks again for being so forthcoming on info. For those of us not likely to be among the six to own an AS-2000, the details are a welcome consolation.

Best,

853guy

Studer/Revox tapa machines used large high quality Papst three phase synchronous motors - the reel motors are even labeled Papst, the capstan models are improved versions of the designs. Besides short time speed constancy, the professional machines had a requirement of long term speed stability and Studer developed a single phase controller that was used in their machines, such as the famous A80, with excellent results - see the Arturo Stosberg paper https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwj_hsiFzMDWAhUH6RQKHfzUBrMQFgglMAA&url=ftp%3A%2F%2Fftp.studer.ch%2Fpublic%2Fproducts%2FRecording_Analog%2FCapstanPapers%2FJAES-69-17-4_AFStosberg_NewCapstanDriveConcept.pdf&usg=AFQjCNHTC8K8XkYUNHMwhwVjCHzqrQ48sA .

However considering the capabilities of current synthesizer circuits we have now the possibility of creating a three phase drive with variable amplitude and optimum shape in each phase if desired, minimizing vibration and maximizing speed stability. As far as I see each of the AS controllers is optimally tuned for its motor. This has been done many times for two phase synchronous motors, only a few current turntables do it for three phase motors.

I tried the trick long ago for the low voltage, three phase small motor used in the Oracle premier - it could run perfectly and silently, but unfortunately the too small motor had low torque and could not run at the lowest vibration point.

 

[Mike Lavigne]

I'm leaning towards having Herzan build me a rigid 2" steel box tube welded stand like they have in the past for me and use the AS for awhile on the rigid table w/o any active isolation devices. At some point I will seek to demo the AVI series active isolation beams under the TT. I feel it may be too risky to buy Herzan's active isolation work station table first and committing to active isolation in the event for some unforeseen reason the TT sounds better w/o active isolation.

What are your thoughts Mike L ?

I am planning to take earlier delivery ....Dec/Jan versus the original March/Early April timeframe.

the (somewhat modified) NDW-23A is my direction. it's purpose built for exactly this application, and with the AS-2000 7 feet from my bass towers I know what the issues will be. the only question will be budget timing, and whether i'll need to have an in between step with a temporary 'salvage' solid table while the piggy bank and wife points re-fill.

 

[PeterA]

My mistake, of course anything the turntable is sitting on and comes in contact with can have an effect. Right now I use some industrial rubber under the tt's feet.



The motor is high torque but but amount of torque and speed is regulated by the motor controller in operation, it's not running at max all the time. There's no servo, feedback look or speed controller. Speed is adjusted by changing frequency in the motor controller you adjust it the once manually according to your electricity, belt tension and motor's parameters. Supplied belt is none compliant but one can experiment with different types including thread.

david

David, Thank you for sharing some details on the belt. Could you clarify one point? Elsewhere in this thread there was mention that the motor distance from the table and resulting belt tension were integral features for tailoring the subjective sound of the table. How is this possible if the belt is non-compliant? A non-compliant belt implies to me that the drive pulley and turntable platter must be at fixed positions to prevent both excess pressure from putting undue stress on both the platter air-guide and the motor pulley spindle and also to prevent belt slippage against the massive platter.

I appreciate learning more about this design and your willingness to answer questions. If the motor is truly noise free, why is the amount of "free" belt so large? I would have thought that the shorter the belt and greater the contact area between belt, motor pulley and platter, the better. I understand that it may not have been practical to shorten the distance between the motor drive pulley and the platter given the need to separate the two and not place the platter above the motor, but in theory, I am curious about the effect of belt length. Perhaps with a non-compliant belt it does not matter at all.

Finally, how long does it take for your platter to get up to correct speed and to stop when you turn off the motor?

 

[Stacore]

Hi Jarek,

That's exactly the design of this controller!

Eh, I have my little doubts The box seems too small for a 470VA linear. I think I saw it in Munich, Christof K had it possibly?

I tried running my 927 free spinning as you suggest but went back to the mechanical brake, I lost something in the sound without it. What improved the sound was using very low viscosity high grade instrument oil instead of what's normally suggested.

david

Great point! But I dont suggest it - to the opposite! What I'm actually looking for is to ADD breaking power and increase the frequency
to maintain the right speed. There is a very interesting interplay here. On one side there is the noise from the felt break. But on the other the break kind of preloads the rotation, possibly masking some of the stylus drag. There may be even a deeper thing - the regularizing effect of random noise. This is a very well known thing in math, physics and psychoacoustics. All of course without overheating the motor, but the speed variations inflicted by the break are very low, well below 1% IIRC.

Cheers,

 

[bonzo75]

What are you referring to that Christof had, Jarek? The motor on his Caeles?

 

[Stacore]

What are you referring to that Christof had, Jarek? The motor on his Caeles?

I think I saw that controller. But I may as well be wrong. May seems like another century to me.

Cheers,

 

[ddk]

David, Thank you for sharing some details on the belt. Could you clarify one point? Elsewhere in this thread there was mention that the motor distance from the table and resulting belt tension were integral features for tailoring the subjective sound of the table. How is this possible if the belt is non-compliant? A non-compliant belt implies to me that the drive pulley and turntable platter must be at fixed positions to prevent both excess pressure from putting undue stress on both the platter air-guide and the motor pulley spindle and also to prevent belt slippage against the massive platter.

I appreciate learning more about this design and your willingness to answer questions. If the motor is truly noise free, why is the amount of "free" belt so large? I would have thought that the shorter the belt and greater the contact area between belt, motor pulley and platter, the better. I understand that it may not have been practical to shorten the distance between the motor drive pulley and the platter given the need to separate the two and not place the platter above the motor, but in theory, I am curious about the effect of belt length. Perhaps with a non-compliant belt it does not matter at all.

Finally, how long does it take for your platter to get up to correct speed and to stop when you turn off the motor?

Effects of belt tension, materials, type isn't unique to this table but it could be limited to certain types based on the design of the turntable. With this type of high inertial platter you want the belt as loose as possible for the platter to spin freely but still at a constant speed, the motor is a major factor in deciding the belt tension. If you want the platter to spin up from standing by itself and reach speed in 30 seconds or less you have to tighten the belt and/or use an elastic type which one can.

There's only an inch between the motor casing and the plinth, not much free belt at all. Spin up and spin down depends on belt tension and the force of the first push, in my setup it's 90 seconds to reach correct speed and the platter will free spin for a couple of minutes or more by itself if I leave the pump on. It doesn't matter in operations when you can change lp's with the motor running, it doesn't miss a beat.

david

 

[Tango]

the only question will be budget timing, and whether i'll need to have an in between step with a temporary 'salvage' solid table while the piggy bank and wife points re-fill.

Talk to Jarek. You might even have a permanent step that cost a lot less, if I may second thought you Mike. And I dont mean his normal product line.

@Jarek. An opportunity arises for you again .

Kind regards,
Tang

 

[Mike Lavigne]

it's interesting and ironic to me that as we approach the 'ideal' of the vinyl format, we get more and more simple, elegant (not easy) and less automatic. we are needing to accept that belt installation and the relationship between the motor and the platter must be tuned by ear. and as belts wear and stretch it will need to be re-tuned. and my own take on that is that it's wonderful that the musical art and it's essential timing is best captured by the ear.....and it will be a matter of personal tuning preference.

 

[Stacore]

Talk to Jarek. You might even have a permanent step that cost a lot less, if I may second thought you Mike. And I dont mean his normal product line.

@Jarek. An opportunity arises for you again .

Kind regards,
Tang

Thank you very much Tang for kindly suggesting my humble self
Actually we are developing a SOTA, high mass, rack system, with absolutely best damping
strategy employed so far to our knowledge. It will feature user interchangeable
"inserts": Either rigid shelves (slate CLD) or any of our platforms.
Should be appear later this year.

Cheers,

 

[spiritofmusic]

Hi Jarek, I don't think I'll be getting that particular platform from you LOL.
Best suited to the guys here who have this beast to deal with.

 

[Stacore]

Hi Jarek, I don't think I'll be getting that particular platform from you LOL.
Best suited to the guys here who have this beast to deal with.

You mean the rigid shelf? The goal is to optimize the support under each component.

 

[Tango]

Actually we are developing a SOTA, high mass, rack system, with absolutely best damping
strategy employed so far to our knowledge.

Hope it looks as good as your current design.
I am interested in your product for my EMT even for just the look of it..hahaha

Tang

 

[Stacore]

Hope it looks as good as your current design.
I am interested in your product for my EMT even for just the look of it..hahaha

Tang

Thank you very much Tang but look is just a side effect here. Wait until you hear it This concept was developed for my EMT930. Im positive it will work absolutely great for 927 too. I could even make you a custom slate plinth when you get bored with the Schwingrahmen