Hum Issues - Rega P-25 w/ Grado Reference Platnum


My friend just put a Grado Reference Platinum cartridge on his Rega P-25. As the cartridge tracks toward the center of the records, the hum increases from non-existant to unacceptable.

Is there anything that can be done about this?

Is it possible to put some type of shielding between the motor and the platter? Or perhaps coat the underside of the platter with a copper-based paint to shield the cart from the inductive interference from the motor?

Has anyone else experienced this?

Thoughts?
128x128nrenter
Hello,

Your problem is normal with your grado cartridge because it is not protected against the magnetic and electric fields from the motor. You have two solutions. First, put a metal cover under the turntable between the motor and the plinth. Finnally, change your cartridge and choose one which is well protected against the magnetic and electric fields. An example, the rega Elys or the old Linn K9.