Quote Originally Posted by 02audionoob
Most warps are on the outer areas of the record, so that's really not the idea of a weight. They could flatten a cupped record from one side, but obviously not both. The idea is to control vibration...not all that different a concept from what you're doing with that pillow.
Certainly a heavier platter would have more mass and more resistance to vibration, but I think my platter weights like 3lbs, would a few more ounces make a difference?

In any case I'm pretty sure that most of the problem comes from the tonearm-headshell-cartridge assembly. I can induce feedback in it even with out it playing, if the volume is set high.