Does Anyone Know the History of the Early Sota Turntables?

I don't know much of the history, but older Sapphires started out with a 3-point suspension. Late models (V and up?) use a 4-point suspension. 15 years ago, I briefly borrowed an older 3-point Sapphire (w/ the gold colored platter), along with the Koetsu-branded Jelco arm, and my very first Koetsu (Onyx non-platinum short body = samarium-cobalt).

The 3-point suspension seemed more "springy" and less stable than 4-points - thus it also seemed more sensitive to footstep disturbances / etc. Star (later called Nova) and Cosmos models always used 4 points. Cosmos is most stable of all (more than my Nova), probably due to the aluminum subchassis' extra mass. But any 4-point SOTA is really, really good. The 3 point tables are still very good, but this is an important distinction IMO. I assume the 4-point might also handle a little more arm mass - though my FR64fx's 2.2 lbs is near its limit (I was told 2.5 lbs max).

The magnetic platter is cool and eliminates most of the shipping problems, but I have to admit the practical performance of the sapphire bearing is pretty darn remarkable. It sure was a sensible solution for its time period, and still viable today. If I was buying a turntable I would think long and hard about either buying a used SOTA and having it restored or getting a refurbished one from them. Apparently Christan at SOTA is producing some videos to document the process of doing spring restorations in the field.

@neonknight I’ve been wondering about that as well. The old sapphire thrust plate and zirconium balls perform SO well, I’m not sure I understand the move to magnetic. It’s also not hard to ship the former correctly.

I’ve had many year now on various Clearaudio Innovations, with their own version of magnetic thrust bearing, and they are VERY reactive to any stray subsonic energy (right in the woofer-flapping range). It can be a huge problem in some systems (and if you think that's bad, the magnetic bearing arms made it even worse). Not sure if SOTA has mitigated this somehow; the further interaction with springs could make it better or worse. I suppose it’s also possible to use magnetic thrust just to *reduce* the load on a traditional bearing, rather than providing 100% thrust / suspension.

Agreed that modern SOTA prices & services are quite dear. When I see a clean SOTA on the secondary markets, it always seems like a smokin’ deal to me. Recently picked up a mint Cosmos that the owner had recently serviced by SOTA (still in their sealed packing) and am grateful to have it. Wonderful table. It’s a series V that has the traditional bearing, but was upgraded to new Condor motor & PSU. I’m not even sure I’d want a SOTA with magnetic bearing, and now I hear their new / upcoming top table is not even suspended? I have to scratch my head at some of the new directions.

A well conceived magnetic bearing should have no "bounce" in response to external energy like footfalls, etc. If it did, you could have the above problems, especially on a TT with a spring suspension.

@lewm Do you happen to know how this is achieved (a well-conceived one, that is)? I’d be real curious to learn. The benefit of a vertical-thrust magnetic suspension is the reduction in friction. The downside being you now have a suspension that can trap energy when excited. And most mechanisms to damp that energy would create far more friction than was saved in the first place.

Clearaudio’s implementation has the downside that they pile LOTS of platter mass on top, and then the magnetic thrust is only "just enough" to oppose this, plus a few pounds for clamping. So when the platter gets disturbed, there’s quite a bit of displacement and visible low-frequency oscillation (and in your woofers if you’re unlucky enough).

Mulveling, Are you saying that your platter in effect bounces up and down on its magnetic suspension when sufficiently disturbed?

@lewm It does so visibly, in the extreme case when I walk by heavily (I’m > 200 lbs) on a bouncy floor with unbraced rack. And in the slightly less extreme case, when playing back at loud SPLs (mid-90 dBs average), large woofers can visibly "flap" - this flapping is NOT present on a rigid bearing non-suspended design like VPI - same room, rack, everything. Of course, those tables have their reactivity in the audible bass range - the feedback even sounds similar to ground hum at times.

Every model of CA Innovation is susceptible to this - I’ve had them all - Compact, Wood, Master. It you push down on the platter it feels "springy", albeit less linear than with actual springs.

The SOTA can cause big trouble too, if the suspension is excited by significant event. But THAT is relatively easy to solve with rigidity in the right places - and the suspension provides a ton of value in its massive isolation of frequencies above resonance.

Yes, I’m aware stacking suspensions is bad news - I’m sure SOTA’s very gifted engineer/designer is aware of that and made sure to avoid deleterious overlap of resonance. I’m just curious about the design of SOTA’s bearing solution compared to the Clearaudios I’m familiar with.

Audiophiles who keep their volume levels below 85dB, and those on concrete slab, will probably never experience the issues I'm talking about.