Has anyone had trouble with speed on their tt

Read Doug Deacon's last post again. He gets it.

Zavato said, "stick with a design that has an AC synchronous motor and a platter heavy enough to have some flywheel effect."

I could not disagree more. Flywheel effect caused by the platter is the reason many turntables lack micro dynamics, or sound lackluster in more general ways. It is a simple case of letting the platter control the speed, rather than the device assigned the job, the motor. That doesn't work, if you want a turntable that is truly precise.

The motor provides torque to hold speed. Platter mass is a component of the drivetrain system and affects how the system responds to changes in load and torque. A high mass platter does more for isolation of the record than the inertia effect. That's because more platter mass requires more motor torque. I have said before that if a motor can bring the platter up to speed in under one rotation, then it probably has sufficient torque. An undersized motor will struggle with the micro dynamics. The motor and platter are part of a system. Any one of the two out of balance results in poor performance.

Correct, Tony.

Except...

System inertia is key here, and certainly not platter flywheel effect like some turntable designers would have you think. I like high mass platters, but where the mass is located is critical, in my opinion. If properly done, the platter can be an extremely important component toward reaching the goal of optimal system inertia. I realize that my view goes against conventional thought on the subject, but I am convinced that the location of platter mass is a big deal.

One day maybe people will see that a platter should be more than a big round chunk of whatever, but right now there seems to be little thought put into platter design. Guys use a lot of different materials in lots of different combinations, but in the end they are still nothing more than big chunks of whatever for the most part. Isolation and tone seem to be the only concerns. That and marketing hype.

Richard, very easy to read with a frequency counter and test record with steady tone. In a fraction of a second I've seen servos change 30 hz when playing a 2150 hertz tone.

Technically whatever it is the proof is in the play back, one outstanding example that will shock anyone that thinks they are familiar with this outstanding RCA Living Stereo recording is Belafonte at Carnegie Hall, Belafonte's vocals are much different, it will stop you in your tracks.
I'm not claiming that I have any answers why this Lp sounds the way it does including others that I thought I knew well, but I think this goes beyond having a table that is capable of precise speed no matter what is going on in the music.