If you look on Vinyl Engine there is an exhaustive study of VPI arm geometry. It exhausted me and I'm a VPI dealer. But it is worth a look. The design of many of the moving coils is not greatly changed from the days when tone arms were typically of much higher mass and with lower mass arms the resonance frequency of the cartridge-arm combination will be too high. Thus the weights to raise the arm mass.
VPI tone arm set up
Wanting to get back into analog, I just completed all my purchases (here on Audiogon) and am ready to start putting everything together. I have a VPI Aries 1 turntable, a VPI JMW 9 Sig. tonearm and a Shelter 501 mk11 cartridge I have mounted to a Cartridge Man Isolator. My question is- I understand the distance between the spindle and tone arm pivot is to be 223mm. Are they talking about center of turntable spindle to center of tonearm pivot? Also, I purchsed a VPI tonearm jig and noticed it only has 1 null point (inner, closest to turntable spindle) where as other jigs I've seen have 2 null points. Will this align correctly?