Does Anyone Know the History of the Early Sota Turntables?

Mulveling, Are you saying that your platter in effect bounces up and down on its magnetic suspension when sufficiently disturbed? So far as I know, the first fully maglev bearing is on the Verdier.  SOTA have it now I think. My Kenwood LO7D platter is partially suspended  in the vertical plane by magnets.  There are others besides the Clearaudio.  Anyway, the Verdier bearing is solid as a rock.  So is my Kenwood bearing, albeit it should be as the platter does make contact with a solid thrust pad while the magnets just reduce the burden. I don't actually know of any maglev bearing that has much give in it so as to allow the platter to move up and down with room disturbances.  Nor can I really say that is a horrible thing. I just ran it up the flagpole to see who would salute it.  But you can imagine that the SOTA mag bearing ought to be solid, because the Cosmos also has a spring suspension. You would definitely not want the platter to be excited while also the spring suspension is excited.

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.

Definitely not rubber, for sure.

In terms of who did vacuum clamping first, what about Micro Seiki, and what about the Audio Technica vacuum mat? Where do they fit in historically? There’s also the Victor TT801. Most likely that latter TT predates SOTA, but I don’t know for sure.

Incidentally, I think the vacuum strength on my Series III was already internally regulated. I don’t recall being able to adjust it.

Except in the case of my Star Sapphire III, the vacuum clamp introduced a faint dull haze over the music. Sounded better with vacuum off.

I am sure the platter speed was well beyond 78 rpm by the time he yanked the plug out of the socket.

I think the Gem post dated the early years and was an attempt to appeal to budget conscious buyers. My anecdote about the platter taking off was intended as humor, but the platter speed was truly out of control and gaining in velocity. My friend discovered he had failed to connect a feedback loop that was key to speed control. The platter did lift up off the bearing just before he cut the power. Believe it or don’t.

The version that Mijostyn describes is probably the one my friend purchased as a kit and assembled himself.

In theory, shouldn’t a 3-point suspension be more stable than a 4-point suspension, all other things being equal? I guess all other things are never equal.

I think in their earliest days, the Sapphire was marketed as a kit. A friend of mine who was technically savvy bought the kit and assembled it. He invited me over for its inaugural spin. This was just a test to see whether it would come up to speed and hold speed. He pressed the start button, and we both watched as the platter spun up faster and faster, far exceeding 33 rpm. In fact, the platter began to lift up off the bearing well, and I feared it was about to take flight, whereupon I ducked under the table. He pulled the plug at that point. Turns out he had neglected to connect something in one arm of the servo system. That early Sapphire was a bare bones TT with a nice wood plinth, not unlike that of the current Sapphire. I think it had the sapphire bearing, but I have no idea about the platter. Anyway, you own one. You are in the best position to assess the build quality and technical aspects.