The thinking in the OP is absolutely right. Any of the old idler-drive TTs will benefit from being sunk into a large/massive vibration-sinking plinth. Most of what was developed over several years for Lencos on "Da Thread" at the late, lamented Lenco Lovers' site --much of which survives now on the Lenco Heaven site-- applies to other brands, too, such as Duals. Reading up on the threads there will give you a good background and appreciation for what might be done, and how.
You'll want to consider slate, soapstone, and laminated ("constrained layer damping") of materials like baltic-birch plywood, as good material to use for the plinth. Make it bond tightly to your top plate (the metal top surface of the player) so that vibrations pass through that bond. Leave as little open space as you can around the mechanisms, except for the motor area, where some airflow is needed for heat dissipation. Also work over the machine to damp and eliminate vibration wherever possible, starting with the obvious candidates like the motor and motor mounts, and then looking at the idler wheel mounting and control system, as well. Check lubrication where appropriate, as well as slack/loose things that might vibrate, and resonant metal connections that might be damped. Get a contact stethoscope and start listening to noises, tracking them down and minimizing them.
You may be surprised at just how much improvement can be wrung out of a typical idler-drive TT, with such an approach. While the Lencos, with their heavy platters and exceptionally simple and precise mechanisms are particularly well-suited to this approach, others such as the Duals can benefit as well. For absolute best sonic performance, simplify the drive as much as you can, removing what you can of the changer-mechanism parts and converting the player to a simple manual unit...however, this isn't necessary for good sound, only if you want to squeeze out that last percent or two of potential performance. Personally, I like to leave them as changers, but still transport them to heavy plinths, for the sonic benefits.
One nice approach right in between using the original resonant "empty box" plinths and the massive Lenco-type solid plinths is to take an original plinth, and "fill it in" to make it solid. Cut boards that fit exactly into the box, with the right cut-outs for the motor and gear mechanisms, and glue them in solidly, but leaving the original plinth as the outer "veneer". The TT will LOOK original, but SOUND much better than the original. This is my favorite approach whenever I find an original plinth that still looks very good cosmetically, and seems too good to waste.
I have always thought it is a real pity that the Technics 1200 II was designed with such a flimsy plinth. It could have been so much better as the driving system is so exceptionally good. All IMHO.
gusten[/QUOTES]
Should I add your name to the list of AKers who own GT-2000s? Obviously you must be used to some such monstrous plinth, if you call the Technics one "such a flimsy plinth"...
