Chakster, on the issue of graphite vs slate, I do owe you an apology if you were talking about mats in the first place and not plinths. The OP was asking about plinths, and I assumed you were referring to plinths made by OMA, which are, or were last time I looked, of slate, not graphite. On the other hand, if you were discussing platter mats in the first place, mea culpa.
I'm also sorry, but your argument about the effect of a high mass counterweight is specific to FR and Ikeda, and I am talking in general about the calculation of tonearm effective mass. A heavy CW, which because of its weight can be placed close to the pivot, can have the effect of reducing effective mass, because the factor of distance between the center of mass and the pivot is squared, whereas CW mass is to the first power. Those are facts. Ikeda didn't abrogate physical laws. If you want to minimize effective mass, you are best off with a heavy CW that can be placed as close as possible to the pivot vs a lighter CW that has to be further from the pivot to achieve balance or the desired VTF. That's all I was saying.
I'm also sorry, but your argument about the effect of a high mass counterweight is specific to FR and Ikeda, and I am talking in general about the calculation of tonearm effective mass. A heavy CW, which because of its weight can be placed close to the pivot, can have the effect of reducing effective mass, because the factor of distance between the center of mass and the pivot is squared, whereas CW mass is to the first power. Those are facts. Ikeda didn't abrogate physical laws. If you want to minimize effective mass, you are best off with a heavy CW that can be placed as close as possible to the pivot vs a lighter CW that has to be further from the pivot to achieve balance or the desired VTF. That's all I was saying.
