VPI Aries 2 platter is creating hum

What materials are the original platter made from? It could be that the old platter was shielding the cart from the TT motor or some other source of electronic hum and that the new acrylic platter isn't providing the same shielding.

Just a guess, but I've found that my Rega table hums--with volume cranked all the way and needle above the record--when it is located above my amp. Moving it to a table beside the amp eliminated the hum completely, so it was definitely not motor hum in my case.

Hi cbrentc, not really sure what material(s) the original was made from. It looks like solid steel. I tried extra grounding on the platter,tonearm and motor with no success. Hum occurred when cartridge met record only. I have my class A amps on either side of the table about 6" apart. Even though the motor is not attached to the table can it induce hum?

You might be able to play with a sheet of aluminum foil to see if you are getting electromagnetic interference from somewhere, it should act as a barrier to the em source. FWIW, made the same upgrade & did not get any ill effects.