Turntable with stable speed.

I agree w/ all that Drpank said above, except that I would advise the OP to consider a couple of things. It is equally important to (1) drive (accelerate) a platter to the right speed, then to (2) maintain it at that speed, and finally to (3) minimize or eliminate friction and other force that will slow or alter the platter speed.

Most turntable designs do a pretty good job at this, some better and some worse. Some are subject to mechanical interference and some to electronic (ex. inexpensive DD decks).

In my experience and not surprisingly, the most stable systems have been those which utilize high mass platters, often coupled to low torque motors. I have always been impressed by the Nottingham turntables for this reason, for example. Also the Acoustic Solid and some other German designs that utilize a similar design concept.

In another example, I have found that a simply replacing the ancient analog neon strobe unit in a TD-124 w/ an LED/quartz unit makes a huge improvement to the PRAT of this deck.

Basis turntables are incredibly speed stable.

TTWeights tables...had 2 and neither was Timeline accurate! (But most know that by now)

(Dealer disclaimer)

Clearaudio Innovation High torque DC-motor, exclusively made for Clearaudio Electronic optical speed control ("OSC") in real time through infrared sensor.Speed accuracy (measured): less than ± 0.05 %
Stump

I strongly disagree about Clearaudio, the DC motor and servo system is one of the worst wow + flutter I've measured. Servo circuits in general are very difficult, you have to pick an error level and time constant. With audio a fast constant gives flutter, slower gives wow, and slower gives too much long term drift. It is the way it is, and higher torque gives no solution. In the Clearaudio case this is played out poorly, (or we could say the weakness of a system like this is demonstrated well) with high speed instability.