One of the benefits of driving one platter with another is reduction of belt creep, and if you do it with a thread, there are fewer of the other issues associated with BD. Everyone who does this swears by it, but we all swear by all the things we either pay big bucks for or that require a lot of effort, as in this case. None of this is true scientific experimentation, but so what.
Just make sure the Denon is really operating up to its max. To do that, you might ought to change out all the old electrolytic capacitors in the Denon for new ones. And then, in the case of any Denon, you are going to have to do some cutting, I think, to enable your thread drive to encircle the Denon platter, since the edge of the platter is not so accessible, and the platter itself was never made to be encircled by a thread or belt (i.e., no groove).
Just make sure the Denon is really operating up to its max. To do that, you might ought to change out all the old electrolytic capacitors in the Denon for new ones. And then, in the case of any Denon, you are going to have to do some cutting, I think, to enable your thread drive to encircle the Denon platter, since the edge of the platter is not so accessible, and the platter itself was never made to be encircled by a thread or belt (i.e., no groove).