Tables That Feature Bearing Friction


I recently had the opportunity to audition the DPS turntable which, unlike most tables, has a certain amount of friction designed into the bearing. This, when paired with a high quality/high torque motor, is said to allow for greater speed stability--sort of like shifting to a lower gear when driving down a steep hill and allowing the engine to provide some breaking effect and thus greater vehicular stability. I am intrigued by this idea and was wondering what other people thought about this design approach. Are there other tables which use this bearing principal? One concern I have is that by introducing friction you may also be introducing noise. Comments?
128x128dodgealum
I think one can some up the problems very simply, but I'm probably just restating what has already been posted here. As I see it the problem is not of design and proper application of physics. The real, true problem is integration. This is true of any complex system, not just with turntables.

You can design and plot and plan all you want. There will still be some compromise or component that you have to go to the shelf for. And then you are constrained by the operation of that component. That is when "feel" takes over, right or wrong. This is true for any complex system in the real world. This is the realm of practical experience and personal preference. This is also the realm of great breakthroughs and great failures.
Dear Mrjstark, if you ever should try different belt materials on a force free lateral (horizontal) bearing, you will observe that the noteable differences in sound will be much less compared with the differences noted in the "standard" (=one motor - no counter spindle) set-up.

Why do we hear so huge difference (I will certainly not deny the fact that there are audible differences with various belt / thread materials and other tweaks in turntable design (mats, clamps, isolator feets, spikes, platforms etc.)) even in state of the art turntables ??

Because these turntables are NOT finished "products" (seen in the sense of a market or as a non-commercial design).
Most likely the designers were under time-pressure and/or seeing the end of the budget and thus need to bring the TT "on the market now".
A "finished" turntable (or any other really "finished" product....) will either show no positive differences with various tweaks or they aren't possible at all due to a design which takes all aspects into count and leave no room for our "add-on", "upgrade" or "tweak"-mentality.

You can't tweak a turntable with force-free bearing running with an aramide or dyneema thread. There is no better material possible so far.
You can't tweak a Minus-K 0.5 Hz suspension by putting spikes or cones underneath. It is already suspended in the best possible way.

We do hear so many differences with so little changes in so small parts because the turntable is so weak.
Because there is so much room for further improvement.
Because we stop too soon.
Because we are satisfied with so little.
Dear Dan_Ed, agreed on the large scale.
And yes, - there will always be "some" (I hardly can write the word...) "compromise".
However NOT SO FAST.
I do get the impression that most designers are seeking for the nearest possible compromise.
That the real goal for most is: finding the best (read: cheapest and nearest....) compromise as fast as possible.
I have no problem with a compromise when there is NO OTHER CHOICE possible. That is early enough.
And frankly - that point will never be reached in turntable design.
We should get real, we are talking about turntables - not about space shuttles, Formula 1 racing cars, atomic submarines or the hubble telescope.
A turntable - a simple mechanical machine....... sorry, I can not see any need for compromise here. And we do not need back-up by the Pentagon or Northorp Aviation to be able to design and build a near perfect turntable.
Ah, so now we are cutting to the chase.

In the real world, there are always compromises. Even the equations that we use to model real world behavior have compromises built in. One can certainly chose which to address, but on cannot avoid accepting compromise in one way or another. Even if one is not aware of the compromise(s) at the time. That is the leap from paper to reality. EVERY system, mechanical or biological or whatever, in the universe has built in compromises. It is unavoidable. So I propose that we drop the pretense that any system can built without compromises.

I agree that all turntable designers/manufacturers will make decisions based on commercial interests. Absolutely. They want to be able to sell what they have made. However, even those who profess to have spared no expense and made no compromises are deluding themselves, IMO. Look closer, I say to them. Compromises are there.
Dear Dan-Ed, yes, are you happy we arrived in the "real world" (was Neo happy when Morpheus showed it to him...?).
Of course, compromises are there. WHERE they can not be avoided I agree to them. However - I can't stress this often enough: the one basic fault is to make the compromise the goal. And that is what is happening all around and what gives us what we deserve: .... mediocrity or worse.

My point is that the compromise is o.k. when there is no close to ideal (= near perfect ) solution possible.
However - once again and for all - it is NOT nessecary in turntable design.
To accept "compromises" here in the early stadiums we see them in almost all turntables around - those are not compromises.
That is poor, unfinished design.

Named "compromise" just because the designers could not do any better or did not want to go any further (for whatever reason...money , time, market call).

"Unevitable compromises" in a machine as simple and small as a high-end turntable............... really, give me a break - we are in the 21st century not in the dark ages of mechanics following the decline of the roman empire !!!
Its poor performance - not unevitable compromise.
Period.