Direct Drive turntables


I have been using belt drive tt's. I see some tt's around using direct drive and they are by far not as common as belt drive ones. Can someone enlighten me what are the pros and cons of direct drive vs belt drive on the sound? and why there are so few of direct drive tt's out there?
Thanks
alectiong
Steve, agreed. My postulate for heavy mass in platters does include that these platters are composite materials which do dampen each individuals inherent resonance behavior. Metal (gun metal, aluminum, lead, stainless steel, copper - all do have their individual virtues in TT-platter application ) isn't "bad" by nature in platter design, but needs "work" - as all other materials - to produce what is possible.

Cheers,
D.
Dear Jfrech: +++++ " And while I do agree with you the only 100% proof on DD vs belt is only to change one varible. " +++++

that's all I'm talking about not questioning what you or other people heard.

Regards and enjoy the music,
Raul.
Raul,
Absolutes are difficult to support in any case.
As you realize, doing a controlled-environment test where everything else (platter and materials, bearing, isolation/suspension, plinth, arm, cart) are the same is quite difficult. I can imagine a technical construct where one could do so, but I have been ridiculed on these pages before for asking about it :^) so even a well-implemented solution would obviously have its detractors. So we are left with the opinions of people who spend a great deal of time and effort trying to "get it right" and each one provides their own opinion based on their own experiences - there are few people who have spent any serious time listening to cutting-edge implementations who would disagree that it comes down to the whole of the implementation rather than a single piece of it. While arms/carts can be moved around from table to table relatively easily so as to provide a 'constant' reference, set-up is yet another issue to deal with. So it obviously comes down to a "in my opinion, in my system" kind of opinion, and it seems that is the spirit in which the posts have been made to answer the OP's questions.
Actually, I was quite struck by the similarity between what someone else just up the thread a bit wrote about the M20FL Super, as compared to my own impressions. That other guy was likely using completely different ancillary equipment, yet his words could be substituted for my own in describing that cartridge. (It might have been Axel, who uses all solid state gear, whereas my electronics are all tubes except for my MM-dedicated phono stage.) I think this is because each of us becomes acutely sensitive to the "sound" of our own complete systems. As a result, there is remarkable consensus (by and large) on the "sound" of the transducers at either end of the chain. Our uncontrolled perceptions may not align so well if the item being evaluated is not converting mechanical energy to electrical or vice-versa. (I use the term "control" in the scientific sense, which is what Raul is really talking about.)
Oops! The above post was meant for the thread on MM cartridges. Sorry. But the point is relevant to this discussion too. However I do apologize for bringing the mention of mm cartridges into this thread.