Vintage DD turntables. Are we living dangerously?

Fleib, What are "DD motor vibrations"? In any decent DD motor, the platter either is the rotor or is securely bolted to the rotor. The stator surrounds the spindle. Thus the only source of vibration is bearing friction, which can afflict any type drive system. Cogging is also an issue for all types of drive systems. I hate to go into this yet again, but in theory one wants the tonearm and the tt bearing to be subject to the exact same external forces so they can respond in unison, resonate in the same way at the same frequency, etc, which should result in minimal dissociation between them in terms of energy dissipation. Thus the stylus is least disturbed from doing its job of following the groove. I'm convinced that this is the best way to go. I am not upset if others do not agree. This IS only a hobby after all. Not that music is not seriously important to me. Another way to say this: "Do what you want".

Truthfully, Thuchan, I think that the major flaw in the much loved Micro Seiki turntables are those cantilevered tonearm mounts. They are much too flimsy to achieve what I am talking about above. Once again, look at an L07D for comparison.

Sorry, Fleib. After reading some of your most recent posts, I see that we are not that far apart in our thinking. Just a little bit apart.

I wonder where is Halcro to argue the other side?

I use gunmetal micro-seiki arm boards cantilevered off of a 20lb steel weight to hold my tonearm. The bottom of the weight is double stick taped to a wall mounted platform. The turntable is on brass cones which are double stick taped to the can, including a critical cone in the center of the can. The cones sit on brass disks which are double stick taped to the same platform as the tonearm pod. Nothing moves independently from anything else.

The ms gunmetal arm boards are massive and allow me to rotate them in order to set the geometry. I use the Feickert protractor. Everything stays in the correct geometry until I deliberately move it.

I can't envision a use for a connection Btwn TT and armpod. But to each their own.

On the subject of platter mats I just want to re-iterate that I am using a lead mat glued to an Achromat. I thought that Fleib or someone else was about to try the same thing and wonder how that worked for them?

Lew,
"I hate to go into this yet again, but in theory one wants the tonearm and the tt bearing to be subject to the exact same external forces so they can respond in unison, resonate in the same way at the same frequency, etc, which should result in minimal dissociation between them in terms of energy dissipation."

That's where we disagree. As you pointed out, motor vibrations might be minimal in a high quality DD, but having arm and platter/bearing subject to the same external forces is a potential problem IMO. What about sound pressure waves hitting the record and plinth? The cart/arm already has to deal with this and might have to deal with it again if it's transmitted from plinth/chassis back to the arm.

I completely agree with Dover concerning BD or suspended tables, but if a DD is firmly planted where is the movement, the moving target? If a platter wobbles, it will wobble regardless.
The goal of controlled energy dissipation is to get rid of cart vibrations and isolate the arm from other ones. I think this is more easily accomplished w/o a plinth/chassis. The final exit of all vibrations should be out the feet otherwise it's just damped, although that might be sufficient.

In the real world either approach can be great or disappointing depending on design, materials etc.
Regards,