A new TT from Steve Dobbins,"The Beat." ???

Mike, Do you know or can you say here just how is the bearing isolated from the motor? It would seem that the very definition of direct drive carries the inherent requirement that there is some degree of association between bearing and motor. I guess the semantics make for confusion. To put it another way, how is it different from the Mk3 as regards the degree of coupling between bearing and motor? Thanks.

Yes, some isolation could be achieved by air bearing as in the Rockport or by magnetics, as in the Clearaudio monstrosity. I don't think Steve used either of those methods. So it's a fun thought experiment to figure out how it might be done otherwise. The simplest thing would be to isolate the bearing from the motor coils as well as possible. Then the magnet/stator could still be attached to the platter, as in the Mk3. No part of the motor physically touches the platter/ bearing in this scheme, so unless there is induced vibration in the platter via the magnet/coil interaction, the goal is brought nearer. With a Mk3, you would have to deconstruct the bearing/coil assembly to get there, which is not easy to contemplate in such an expensive and rare piece of gear. But my goodness, the Mk3 is freakin quiet already.

No doubt the platter and mat have a huge effect on the sound of any tt. This is a universal issue, not just restricted to dd tts. Problem for me is that I don't know what is "the best". In general, high mass seems like a good thing, but after that there is a lot of room for speculation. I believe that high mass is less critical for dd tts than for belt-drive types. I guess if one had the cojones to try it, one could unbolt the magnet from the Mk3 platter and attach it to a platter of one's own design and thereby fit the new platter to the Mk3. A company like TT Weights could make such a platter (and of course Steve Dobbins can make a fab one).

Kftool, Since the platter of your tt is probably bolted to the top of the motor to which the magnet is fastened, in a sense you are free to change the platter, as is true of most dd turntables. The Mk3 is the exception rather than the rule. Most dd turntables are like yours. But the restriction is related to platter mass. The drive system was designed for the mass of the platter, and if you change the platter mass dramatically, then the servo mechanism will not work correctly. Problem is that the permissible range of variation in platter mass for any particular dd setup is unknown to most of us. It's safe to say, I think, that with a massive motor, like the one you have in your DP308, you can probably increase mass by at least 20% without any worries. Probably that is a conservative estimate. The only way to find the upper limit is to do the experiment. As to your other point, I do not know to what degree a heavy platter would work to resist airborne vibrations. Only way to do that is to move the tt to a sonically dead part of your listening room or to outside the listening room, IMO.

PS. You're a lucky guy to have a DP308 and the space in which to place it.

Ken, I keep forgetting that we are near neighbors. We should get together for a dd fest one of these days. Lets make email contact. Howard serviced my L07D and it is now in use. SP10 Mk3 will soon follow.

Interesting thing about the L07D is that Kenwood planned for increasing platter mass by providing a switch on the PS that alters the servo when one is using the optional peripheral ring and center weight. In addition, there was an optional ceramic mat that added yet another 1.4 lbs. Someone else calculated that the servo and motor will take up to 21 lbs of platter mass.