Is Direct Drive Really Better?

MJ and V: Obviously we can't achieve a correct 1:1 correspondence, or probably even seek one realistically speaking. (Although if that were the goal, then you could make the argument that going with a Technics SP which used the same motor/controller as a Matsushita disk-cutter would be a reasonable strategy. However, lacquers aren't the same as vinyl, cutter-heads aren't the same as cartridges, and of course inscribing a groove isn't the same as following one.) The real point may be that, even were we able to achieve "perfect" playback with zero speed distortion (which we can't), if the record weren't cut the same way, you'd still wind up with speed distortion. Boiled down: You'll always have speed distortion. But we already knew that.

As to Viridian's observation, if our theoretical turntable suffers less dynamic drag on transients than the cutting lathe (maybe not as unreasonable an assumption as it might seem, given the presumably much greater frictional resistance encountered by a cutting-head in inscribing the groove as opposed to a stylus merely reading it), then pitches will go slightly sharp on transients. If the turntable suffers more dynamic drag than the lathe on the other hand, then transient pitches will go slightly flat. All in all though, I don't think it's completely unreasonable to speculate that these speed distortions at the mastering and playback ends might indeed have some rough natural correspondence which tends to mitigate the problem more than exacerbate it.

Expounding a bit: Viridian, your last question I think may really concern phase. You might be thinking of "flanging" as an analogy, or the way loudspeakers behave regarding crossovers and multiple drivers or reflective room surfaces. If so, that would not apply to this situation, it seems to me -- that sort of reinforcement/cancellation phenomana requires mixing of more than one sound source, which I think the encode/decode of vinyl playback doesn't qualify as. You are right that pitches are affected, and the resulting pitch distortions will derive from addition and subtraction, but I don't believe there is any constructive/destructive reinforcement going on as I understand the concept. For instance, to "flange" as they originally did in the recording studio, you need two reels of tape both with the same signal recorded on them, played back in synchrony, which is then modified by applying friction via the engineer's hands to the reels' flanges. But if you recorded one reel of tape while altering the pitch by applying drag to the flange, and then played that pitch-altered reel back while doing the same thing again, the "flanging" effect would not be the result, just further pitch distortion.

This is good!

Macrojack, I built an idler wheel table from a Lenco and I would not consider myself to be a DIY guy (although I am getting better) - it's not that hard if you have the time to do it. You cut some plywood and MDF to the same size, cut out the cavities for the guts of the lenco to fit inside it, glue the layers together, bolt the lenco onto the plinth, finish with self-adhering veneer or stain it. The veneer covers a lot of the mistakes. If you use the right arm or turn the thing 90 degrees, you don't need to cut the base plate to set the arm. You clean the motor and the bearing, stick some dampening under the plate, and for $500 you're stunned.

I don't have an opinion about which is better in the drives, but I will say without any reservation that I have enjoyed the hell out of mine. If like me you really get turned on by value, well, this is a real value in audio.

Plus you get to tell people "I built a turntable" and that in and of itself is worth the effort.

Lenco's are on ebay all the time - there are some specific models to buy and some to avoid. I used an L 75. I think the 69 (someone correct me if I am wrong) is also good - these have aluminum idler wheels rather than plastic.

So, if you really are curious, I am your role model. If I can do it, you can do it.

Dear Zaikesman: +++++ " Raul: I think your focus on speed-accuracy may be overstated. IMO speed-stability is the more important factor, beyond a certain point of competence concerning accuracy. Accuracy isn't that hard to achieve, stability is. " +++++

No, definitive I don't agree with you: ovbiously speed stability is a critical and very important TT subject but first than all we need speed accuracy, that's mean that first we need that the TT drive system runs exactly at 45 rpm ( example ) not at 44 or 46 rpm. It does not matters that a drive system has good speed stability if not has speed accuracy. In my opinion first we need speed accuracy and the second most desired characteristic is speed stability.
I don't agree too with : ++++ " Accuracy isn't that hard to achieve " +++++. I think that you are only " talking " ( with all respect: brain-masturbation . ) with out any scientific info that can confirm your statement. If it was not hard to achieve then we should have several TT with a speed accuracy of 0.001% and we only have two of them. Where do you learn or which are the facts that confirm your statements?

Here it is another of your BM that have no value at all because this BM can't be corroborated for any one ( you are accelerate your " car " in " neutral " . ):

+++++ " If a TT slows a bit when it encounters increased stylus drag, then a lathe must also slow when it cuts more highly modulated passages into the blank lacquer. To read the information as accurately as possible, the playback should read those grooves with speed distortions that correlate with how it was cut. " +++++

I'm not saying that you can't have all those BM that you posted and many more, what I try to explain is that those BM don't permit to any one to go any where.

I suggest that because you are very interested on this thread make a extensive research about your statements and share with us the facts that you find it.

Dear Zaikesman, you statements in their today status confused to many people and what all we need here is to have a clear and precise information on the thread subject with out speculations that can be corroborated.

Regards and enjoy the music.
Raul.