Brinkmann vs TW Acustic

This may end up competing with Raul's thread for longest on the website, but it also competes with the now defunct TV series, "Seinfeld", in that the subject is "nothing".

Thuchan, I have to disagree with you. At least in theory it should not be best to place the motor drive of a belt drive system on a completely separate support from that of the turntable itself. This is a cardinal sin of bad belt-drive turntable design. (The commercial product analog is to use a suspended chassis bearing the platter and tonearm whilst the motor drive is fixed to the inert plinth.) This results in some of the most obvious "wow" that I've ever heard in vinyl reproduction. The original AR turntable was guilty of that infraction, as were the early SOTA turntables. Especially, to put the turntable on a Vibraplane or similar device and the motor on an inert shelf system is asking for trouble.

Heradot, I doubt that any of the 260 lb Vibraplanes are sliding away with the addition of a record on the platter. My point is that because the Vibraplanes (and other air suspension systems) need a compressor to remain inflated in the long term means that at some interval, the air bladders need to be filled up again slightly. My compressor goes on for about 5 seconds every day or two. I can't hear it so it does not matter. It is supplying three Vibraplanes with 270 on each unit so there is a lot of pressure and air does escape slightly.

Because the unit needs air occasionally, it is changing very slightly in height or level or both. That is why it has automatic self-leveling. It follows that any part of the turntable system (motor, flywheel etc) should not be located on a different surface if absolute control of the dimensions within the system are to be maintained.

Perhaps this is only theoretical because it may not be heard, but then we are also talking about the accuracy of the Timeline vs the KAB and other devices. To remain consistent, if one argues for the Timeline, he should also argue for a fixed/closed motor pulley to platter distance, spindle to pivot distance etc, etc. How can it be otherwise?

As far as the thread is concerned, all of the Brinkman and TW Acustic BD tables I have heard and seen maintain this fixed motor to platter distance because they are placed on a common platform.

Peterayer,

Thank you for explaining in more detail. This thread isn't making too much sense. Too many contradictions.

I am surprised you needed isolation for your SME. I thought the O rings would do the trick. But when I think about it, it makes sense. Nothing is as god as a separate platform. The first time I "heard" my Raven was after isolating it. Even concrete floors make standing waves.

I just don't believe any turntable can be judged until isolated. I hunk the best solution is a singular isolation system for the entire analogu system, and maybe Independant platforms to absorb energy on top of the isolation platform separating the motor and turntable. Maybe even the Tonearms if you want to be obsessive. I am just happy so don't worry too much. I just need better vinyl or really the Audio Desk system so I can get more listening time.

Dgad, There are two other things that could account for the improvement to the already good isolation of the O rings on the SME. First, the table is sitting on a different surface now. I tried it briefly on the wood top shelf of my DIY rack. Not it is on 286 lbs of steel and so the energy is draining down into a larger mass. Second, the motor controller is now isolated on the steel and Vibraplane from floor born vibrations.. Both contribute to the improvement.

"This is a cardinal sin of bad belt-drive turntable design. (The commercial product analog is to use a suspended chassis bearing the platter and tonearm whilst the motor drive is fixed to the inert plinth.) This results in some of the most obvious "wow" that I've ever heard in vinyl reproduction. The original AR turntable was guilty of that infraction, as were the early SOTA turntables. Especially, to put the turntable on a Vibraplane or similar device and the motor on an inert shelf system is asking for trouble."

Good point Lew...
My previous T/T (an LP12) was prone to a phenomenon some referred to as "breathing". (Note this could also be related to platter balance issues)
If you positioned your eyes level with the platter and checked the top plate clearance you could see the platter edge/clearance oscillate due to the pull of the belt.

The turntable sounded very musical despite this effect :)
Kind regards.....