Acoustic Signature turntables

@plinko , To start off with I am not a big Acoustic Signature fan. Having said that and to answer your questions;

Multiple motors are a totally unnecessary expense and complexity. A single motor with modern controls and a platter the right mass or angular momentum can not be beaten.

Bearings with magnetic or air thrust mechanisms are bound to last longer and be quieter. I prefer magnetic as air bearings have compressors that will fail long before any good mechanical bearing will. 

I prefer AC motors as they automatically torque correct to follow the established frequency. DC motors will not although DC motor control has come a long way.

There is no such thing as an overly damped platter while a ringing platter is a horror show. Many platters are adequately damped by their mats. I prefer single piece platters as I always lean towards simplicity. 

A platter can be too heavy depending on the motor. They are also slower to start up and slow down. Many platters are now grotesquely oversized. I think it is that male bigger and louder thing.

You missed two features that are important for the absolute best performance and that is an isolating suspension and vacuum clamping.

@mijostyn , thanks for your comments

Multiple motors are indeed a major concern with the AS tables although possibly better for bearing life as the pull on the bearing is minimized.

For magnetic bearings, do they have any possibility of changing over time? I do not want to be in a situation in the future of managing the height of the motor spindle to a bearing/subplatter/platter that has changed in height. I also do not like the idea of managing air bearings over time.

I thought the main reason for a heavy platter was inertia and would also be the same reason to take longer to get up to speed. My concerns here about high mass tables are about overdamping and a less than exciting sound. The two AS tables took about 35 seconds to get up to speed. Kuzma says 2 seconds for the Stabi R. I would guess torque is a factor and higher in the Kuzma tables (?).

I eliminated suspension for the typical reasons…the movement/swaying and changes in position over time and/or realignments needed. SOTA was eliminated because I cannot see one in person…no dealers in all of New England, sadly. That is an absolute must…I have to see some examples from the brand in person. Clearaudio was eliminated because concern about magnetic bearing and stability. TechDas seems to have been eliminated as perhaps out of my price range, air bearings, and other factors. I may be completely wrong in this way of thinking and not saying these tables are flawed in any way.  I don’t know and part of the real why I started this thread.

In my case, I wouldn’t call this a macho, male thing but would admit there is a pride of ownership or objet d’art aspect to this. Although many people wouldn’t find anything artistic about these devices…

Btw, I also eliminated non suspended tables that do not have the motor, bearing/platter, and arm on the same plane or, at least I think I have. ;-)

Dear @mijostyn ​@plinko  : I agree that we can't overdap the TT and even if we could that's a good notice.

In the otherside AS TTdoes not needs multiple motors, more than one is only an alternative for the owners. It's really need it more than one? certainly not. I used mines with one motor with out any single issue and this I do for several years. Even that I made tests time to time with a second motor playing and in no time my way of thinking about changed.

About motor torque per sé means nothing because all is relative to the overall TT design. The AS is low torque because has a heavy platter that under playing only needs little help to spin due to its very good inertia. Overall design defines TT characteristics.

When using my units I give it a little help with my hand just to start and spinn at 33rpm in no more than 10seconds. Not big deal..

R.

AS turntables are great!  I used to have the Mambo and still regard it as one of the best turntables I own.  I regret selling it.  Stick with AC driven platters.

Rumor has it the Levinson 5105 TT/Arm is an Acoustic Signature manufactured in Germany system.