Is Direct Drive Really Better?

Teres: You *elected* to implement it with direct-drive. Why? Marketing (which I think may be a good move in a crowded BD universe), and/or something more?

PA: You lost me, I don't understand the meaning of your response to my wisecrack (which was only in reference to "watching women's palms" -- intended as a joke, though I'm guessing you're not joking about anything...)

Zaikes, if you think about for a minute, moving to DD for marketing reasons alone would be a huge gamble (some might say insane), to say the least, from a business point of view. I've worked for start-up companies for almost 12 years and I can assure you if you swim against too strong of a current you will drown quickly. Chris can certainly speak for himself, but based on everything I've heard about him I doubt there is anything short of a sincere desire to improve the current state of the art being offered from Teres. Healthy skepticism is a good thing, pessimism is another issue. Especially when it is expressed from a position of absolutely no first hand knowledge of the table in question. But you are entitled to your opinion. I'm not trying to throwing darts at you, maybe just spill a little beer on your foot. :) Where did the animal go?

P.A. may be waiting for me to apologize for calling him psychotic although, if he really is psychic he surely knows I meant no harm.
I've assumed from first hearing of it that Teres is looking to raise the bar not the bar graph. If Chris was looking to sell more tables, he'd be designing Teres Jr. for mass consumption rather than some ambitious project that I won't be able to consider buying.

I was sincere in my question to Teres -- not pessimistic, only a bit prodding. I think it's possible to do both (good marketing and good design; there's nothing wrong with the former as long as it serves the latter), I just sense he's downplaying the reasons why Teres is, in your words, taking "a huge gamble". For all the reasons you list why this wouldn't be undertaken lightly, it's hard to conclude anything other than that Teres does believe that DD holds more promise in some important way(s). I want to know why.

Zaikesman, I have to admit that the direct drive choice was based almost entirely on theoretical reasoning. The initial quest was to produce a better quality motor using some new techniques that I had been musing about for some time. When examining drive methods it looked like DD had the most potential (ie lack of compromises). But at the same time it also looked like the most difficult and risky approach. A little isolation can cover a lot of motor sins and with DD you get none. I also looked closely at idler drive. From a theoretical perspective it seems that idler drive is somewhere between BD and DD. Some isolation but less than with BD. I happen to think that idler drive has a lot of potential and suspect that at some point I will experiment with it.

In the end I settled on DD because I believed that this new motor would have low enough torque ripple that DD could be used without compromising the smoothness that is characteristic of a good BD table. Our first DD incarnation confirmed my theories. It had great pitch stability, drive and rhythm but sadly lacked smoothness and refinement. But with some considerable effort the smoothness and refinement has now surpassed our best BD motor. So is the success due to the motor or the drive method? The answer must simply be yes.

Fortunately, or unfortunately, marketing had little to do with the decision. It's going to be difficult to recoup the development costs for the DD motor. Sadly the motor is expensive to produce so I doubt it will ever be sold in volume. But I can say that it has been one of the most personally rewarding ventures I have embarked on.