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
128x128alectiong
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i beleive that direct drive is far from a fad. look at the Teres and others. they are very expensive (and state of the art?) but we might see the technology come down in price over time. I am surprised to see the comment that linear tracking arms are considered passe as well. I think the rim drive is a highly viable option. if you are looking for a good option within a "reasonable" price range, a belt drive offers many options.
I've had many belt and direct drive units and the sound differences have all over the lot. Present belt is VPI Aries I, also running Denon 47F, a direct drive. While the Aries does beat the Denon, the diference is close and could be the cartridge or SDS on the Aries. I also run a Sony x800, direct drive, linear arm with a Grace Ruby. It often sounds as good as the Aries. I have listened to the VPI rim drive and found it transmits vibrations to the table and these apparently degrade the sound. Could be a defective unit or set up error. Overall, belts are the best value, at least for now.
I think many DDs, even in the early 1980s when TTs were at their volume peak and technology development costs could be spread over a large number of units, were hampered by less-than-ideal implementation of plinth/isolation features. Because BDs usually have an outboard belt, and a smaller motor which vibrates the platter bearing less (ceteris paribus), it is easier/cheaper to make a BD TT with acceptably low self-generated noise issues than it is to do the same with DD TTs. It was that way in the golden age and it is that way now. Also, a big high-torque but very quiet/smooth direct drive motor is a very expensive thing to make these days. If one can defeat motor speed stability issues on a BD through the combination of belt/pulley slippage being overcome by supremely mass-y platters, it is easier and less expensive to do a BD TT.

At the top of the heap of the best BDs and the best DDs, among all the tables and technology implementations I have heard, I find isolation and platter weight to be far more important than most people give credit for.

As it is, the best DDs from the past can easily compete with BDs of now for similar money (I would say they generally beat tables of now if one is willing to put the same amount of money into it). That said, you buy used, spare parts are limited, and there is rarely any significant manufacturer support (I have had Exclusive and Denon tables repaired by mfr-sponsored repair subsidiaries. I know Sony will. I know Kenwood won't, and lots of Pioneer, Sanyo/Otto, Technics, Sansui, Hitachi, etc owners are plain out of luck.