Turntable speed accuracy

"You would not use a Pabst motor in a direct-drive turntable"

Lewm
Pabst is a company that made many motors. The external rotor one used in the Empire(Atmaspere)turntables is merely one of their products.
They made dd motors for Revox and Goldmund and I I believe they also had something to do with the Dual eds motors.
The external rotor one was used as an upgrade for the TD 124 and the also made a dc motor for belt drive that was used in the early SOTAs.

I meant to say that Thorens offered an external rotor papst 3 phase motor as a replacement after they stopped making the original induction motor for the TD124. The jury's out on whether or not it constitutes an upgrade.....consensus on an audioasylum thread was that the original motor was preferred. I suspect it's because the papst 3 phase doesn't like being slowed down by the eddy current brake. With a proper 3 phase variable frequency power supply and setting the eddy brake to minimum I think the situation could well be quite different.
Lewm, your (and other's) journey of discovery with respect to direct drives & lencos is inspiring me to take the plunge and go down that path.
I'm planning a diy using the dual eds 1000 motor and I also have a Lenco GL78 I want to play with.
I'd also love to get my hands on a Denon DP80 or 75 .

Lewm asked, 'What Turntable', I'm thinking that he was asking what Magnepan was using at the CES.
Memory of 30 years ago tells me it was a Linn Sondek, but that seems wrong...
Funny, Linn ruled for a while, when SOTA entered. Sota which was more neutral, maybe less 'musical', but they did some things that were 'better' from a design standpoint. The center of gravity, with weight sprung beneath the platter...for better stability and less 'skip' with 'footfall' issues in homes.
That, and an 11 pound platter, for greater 'speed stability'...the inertial effect of the 'drag' of the cart, having less effect as the inertial effect of that weight made for fewer speed issues in the short term/time interval.
I still have a Linn, that's not been used much AT ALL...perfect condition...I may sell it...my vinyl has dissipated over the years.

Great discussion and a great memory lane moment for me.

Larry

I owned a Sota Star Sapphire III with vacuum for many years. It was eclipsed handily by my Nottingham Hyperspace, which revealed to me that piano music does not have to have the wavering pitch that I always heard with the Sota. In fairness, the later Sota products are said to be much better in this regard. But then in turn the Notts was eclipsed by the Lenco and direct-drive, IMO and in my system. Actually the contrast between the SSS III and the Hyperspace may have been greater sound quality-wise than was the contrast between the Hyperspace and Lenco. I think the pitch instability of the SSS was caused by belt stretching as the platter bounced on the spring suspension whilst the motor stayed still because not suspended.

Lespier, Thanks for the information. When I wrote what I wrote, I was thinking of the seminal Papst motor, as used in the Empire tt's. I actually thought that the term "Papst" (Pabst?) refers to a particular motor configuration, patented or invented by someone named Papst, not to a company that makes a wide variety of different kinds of motor. But maybe you are inferring that the Papst type motor can indeed be adapted to direct-drive. Good idea with the Dual motor.

Hi Lewm. Papst made a huge variety of motors. I think the company still exists and now makes industrial fans. I haven't seen the external rotor type being implemented for dd nor do I think it would be a good idea to try. They did make a number of dedicated dd motors though . The SOTA turntables (as well as many other brands in the 80's & 90's) used a papst dc 'pancake' motor up to series iii . I did have a star iii as well and now now use the platter, bearing and vacuum pump in a DIY tt but with a different motor.