Tables That Feature Bearing Friction

I believe some models of Jeep/Chrysler used hydraulic cooling fan motors powered by the P/S pump due to the fact they are quieter.

I would speculate that the main reason for using a hydraulic motor is more to do with the high-temperature environment in which the fan motor must operate, especially if used on the back side of the radiator. At these temperatures, copper conductors get pretty lossy, and when running a 12V motor (drawing 20-30 amps), they start to really add up . . . in windings, commutators, brush leads, wiring, relay contacts, etc. And then you've got make up for those losses in power generation . . . and when a cooling fan is most important is when the vehicle isn't moving, hence engine speeds are low, and the alternator suffers from poor effeciency. In this application . . . hydraulic makes lots of sense.

But for a turntable, both air-vane and fluid-vane motors are far from vibration-free and cogless (go to an auto-body shop and listen to their air-vane-powered tools) . . . so there will be similar challanges as electric magnetic motors. Maybe an expanding-chamber screw-type armature fed by high-pressure hydraulic fluid? Then the problem is that you've got NO speed feedback, not even the fixed-frequency rotating magnetic field in an electric motor, and there's been disapproval voiced for a feedback speed control system.

Believe me, I'm not completely poo-poo'ing the idea, but rather will be extremely impressed if these challanges (and all of the others that I've not thought of) are able to be solved. And of course I'll want to read all about it, so do keep us posted.

Dear friends: IMHO the subject on speed accuracy/stability in TTs are almost addressed and solve by almost all the TT designers and manufacturers. We can take examples like Technics, Denon, Rockport, Walker, Kenwood, Basis, Pionner, SME, Monaco, Sota, Raven, etc, etc, where we find very good numbers on the subject that goes as low as 0.001% ( speed subject ) and figures on SN of 92db or WF of 0.015%.

So one way or the other ( different TT design approaches ) the spedd accuracy and speed stability are already achieved by commercial TTs.

Where I think there are a non-definitive solutions are ( like other people point out ) in self TT isolation and neutral build materials on each commercial TT design out there.

As Dertonarm poin out, the TT must does not have any " sound "/signature by it self that can add some kind of distortions/colorations that affect the cartridge quality sound reproduction, the TT must be " dead neutral ".

If we read any TT subject thread in this forum or in any other one we are reading things like this: the bass in this TT has a better bass that the other TT, it is warmer that the other ones, it is more alive that the others, the high frequencies sounds better, everything sounds lower in record noise, etc, etc, etc.
There is always a TT sound, so these TT are faraway to be neutral ( that is our target like customers. We are full of distortions/colorations to continue to accepting more. )

IMHO two main factors that contribute to those each commercial design TT " sounds/signature " are due to a poor isolation and what were the choose on build materials ( including the arm board ).
I think that is here where the commercial TT designers/builders have the greatest " room " to improve and achieve " neutrality ": for to have a TT running with speed accuracy and stability with out adding/removing almost nothing.

I think that the challenge is a big one but with a lot of rewards when solve for everyone.
The build material issue is critical, you can take how important is when you try different TT mats in your own TT: you have different sound quality level as different are each one mat and its build material.

This build material challenge is enormous if we take in count that exist hundred/thousands of build materials that can be use in the TT manufacture and million of blend/combination materials that could be use it, so not an easy task to have the " answer " but IMHO if we want to have better TTs ( any kind of TT. ) then we have to ask for to the commercial TT builders. I think that the " ball " is in their hands and I hope we can see in the near future ( and can buy ) that " neutral " TTs in favor of the analog music-sound home reproduction.

I know it can do it because I already experienced and " solve " something similar with our tonearm design.

Regards and enjoy the music.
Raul.

Other subject that I would like that the commercial TT designers/builders could address and solve is to have a record " perfect center " mechanism.
This out-off center record hole is a " cancer " in the analog quality performance ( due to an extremely poor build quality of the record industry. ), we need a solution. I think on the TT builders because I don't think that the records industry can " hear " our needs.

There are other " desirable " characteristics that will be welcome in a TT design but for now I think these ones are enough.

Regards and enjoy the music.
Raul.

out-off center record hole is a " cancer " in the analog quality performance ( due to an extremely poor build quality of the record industry. ), we need a solution. I think on the TT builders because I don't think that the records industry can " hear " our needs.

This was made 25 years ago from a Nakamichi Turntable. It centered the record automatically.
Too expensive for our days I guess.:)

Yes, I know: the Dragon and TX1000. A friend of mine in San Diego and other one here own these units.

Raul.