I am not a fan of servo controlled speed. The speed is wrong a lot of the time!
A properly designed turntable should run at a constant speed!
If there is stylus drag (that audibly effects sonics) , then increase the speed slightly.
I like the VPI SDS - regenerated AC - a variable Quartz crystal controlled frequency in steps of 0.01 Hz - after startup reduces voltage for lower noise - modified sine wave for smoother motor rotation.
It made a "huge" sonic difference on my TNT III, when the speed was set with strobe disc.
All the VPI Classic turntables need the SDS, even though it was originally made for the TNT line.
A properly designed turntable should run at a constant speed!
If there is stylus drag (that audibly effects sonics) , then increase the speed slightly.
I like the VPI SDS - regenerated AC - a variable Quartz crystal controlled frequency in steps of 0.01 Hz - after startup reduces voltage for lower noise - modified sine wave for smoother motor rotation.
It made a "huge" sonic difference on my TNT III, when the speed was set with strobe disc.
All the VPI Classic turntables need the SDS, even though it was originally made for the TNT line.