Is Direct Drive Really Better?


I've been reading and hearing more and more about the superiority of direct drive because it drives the platter rather than dragging it along by belt. It actually makes some sense if you think about cars. Belt drives rely on momentum from a heavy platter to cruise through tight spots. Direct drive actually powers the platter. Opinions?
macrojack
Anybody seen the new Grand Prix Audio Monaco DD described in April's "Analog Corner" CES report? Quothe Fremer: "Ultra-compact...magnesium platter...bronze flywheel...CPU-controlled...5,000-point optical reader...platter which is also the rotor (sound familiar?)...only mechanical attactment point is the bearing, no contact in the horizontal plane...composite polymer-damped plinth...aluminum billet armboard...$15-20K? Albert? You getting one of these for review to go with those racks? Now there would be a DD vs. BD showdown for you.
Rwwear, I have not read that thread. Can you tell me what a SP-10MKIII is?
Even a 1% static error alters the essential character of the music only very slightly, and even then usually only in direct comparison with the correct speed.
Alex,

That's the first statement you've made that I'll specifically disagree with. Given sufficiently transparent yet harmonically complex music, a 1% static speed deviation is quite audible. The music's harmonic structure will be damaged.

I'm not referring to anything esoteric. Mozart's orchestral scores are a good test. Nothing seems simpler, but his harmonic relationships are far more tightly inter-related that is usually appreciated. Change playback speed by 1% and they fall to pieces.

To be fair, this does require a very transparent sytem to be audible. Bloat or overhang from any component will readily mask the harmonic damage from a 1% static speed error. My old c-j and Bent components did. So do Aesthetix and Supratek, for that matter. Dan_Ed, Jyprez and Swampwalker could attest that our Nick Doshi stuff has the requisite transparency. When they visited recently I didn't specifically demonstrate the audibility of a 1% TT speed error. But I could have.
Phd, the SP10MKII is an upgrade from the Technics SP10MKII that has a 28lb bronze and aluminum platter and an outboard power supply with speed control.
"Speed-stability is the crucial issue, not speed-accuracy within reasonable limits."

Zaikes ... I agree with you. If speed accuracy were more important the CD vs LP debate would have died long ago.
Speed stability is what really counts.

Regarding the limit of discrimination this reference has it at 0.5%
http://www.indiana.edu/~emusic/acoustics/pitch.htm

So you could argue that the difference between 0.001% and 0.01% is academic. I would even argue that the orchestral players are not able to tune their instruments to better than 0.1% so you are fooling yourself if you think a turntable needs to be substantially more accurate.

Since speed stability problems cause direct distortion to the waveform they are much more noticeable.

Doug ... how does an absolute speed error break harmonic relationships ? If we are 1% fast then a lower A is 444 Hz (instead of 440Hz) and an upper A is 888Hz instead of 880Hz. The doubling of frequency per octet relationship is still maintained, just shifted slightly 1% up in frequency.