Linear Power Supply?

Like I said, it's a matter of individual perception.  Is there likely to be a measurable  advantage to the LPS vs the existing SMPS, in terms of noise in the audio signal or speed control accuracy?  No, I don't think so. But will you hear a difference? Maybe, because of how our brains work.  Brinkmann has for years offered a tube-based motor controller as an optional extra cost item compared to their standard solid state motor controller.  I can't think of a reason for it, but many end users report an improvement with tubes.  (The present situation is not analogous, of course.)

@earthtones , I have a Cosmos with The Phoenix Drive system. It is perfectly normal to see a variance up to +- 0.005 RPM. Mine runs 33.336 +- 0.002. Never in a million years will you hear this. The Phoenix drive also buffers whatever power it is getting. There would have to be a very large variation before it would effect it's performance. I have watched the Road Runner with all sorts of power dipping events and nothing seems to bother it. 

@lewm I was going to mention the Brinkmann tubed power supply. I’ve read that it’s better but I don’t recall anyone giving a good reason why it should be in this application. Now I’m a firm believer in tubes in the amplification chain of my system, but here we’re talking about driving a turntable motor accurately. So, as with the sparse info given on the Brinkmann the last time I checked, I similarly remain unconvinced about LPS benefits in this application. I’m not writing it off and I might just try it..

This is an exercise in frustration for me. A whole lot of words but no mention of specifically WHY and HOW. If I were interviewing someone for a programming job, they would not impress me with this sort of vapid marketing speak:

https://www.brinkmann-audio.de/main.php?prod=roent3&lang=en

I am not knowledgeable enough to concoct an explanation for why a tube based motor controller might outperform a solid state one, for performing the function required in the Brinkmann system.  But I do know that such a rationale exists somewhere, if not on the Brinkmann website.  Several years ago, Mark Kelly, a very smart super-hobbyist, developed a tube based motor controller for the Garrard 301 motor.  Mark could give you reasons why he chose tubes for the application rather than solid state devices.  Prior to developing his tube unit, he had already perfected (and sold several) an SS motor controller for the 301.  He built maybe a dozen tube units before going in to business building and selling wood bicycle frames, in Australia.  But it ought to be repeated that none of this has any bearing on the Eclipse system, where the issues are different, and we are only talking about a PS, not a motor controller.