SME V effective mass.......again


I want to change the effective mass of my SME V from 10-11 (normal) to 15-16. If we assume that the arm is 10 inches long and the c/balance weight is 1 inch from the pivots then I know that the counterbalance is 10 times as heavy as the cartridge end. If I add more mass to the cartridge end I can re-balance the arm by either moving the c/balance weight away from the pivot or add more mass to the existing c/balance weight. In both cases what has happened to the effective mass?
clarkie

Not very much.

If you add 5 grams to the cartridge end and counterbalance this with 50 grams increae to the CW, the net increase in effective mass if 5.5 grams.

If you add 5 grams at the cartridge end and counterbalance this by moving a counterweight of say 100 grams back by 1/2 the existing distance the effective mass will increase by 6.25 grams.

Formulae supplied on request.

Mark Kelly