grado reference statement hum

I just purchased a grado reference cartridge for my wilson benesch table with act.5 arm. I am getting hum when the arm moves closer to the motor (end of record). This did not occur with the ply cartridge that came with the table. Any thoughts? How to cure?
I can't speak for this Grado.I have a Silver Grado with VPI MK3 Table,and was at one time having problems with mine similar to yours,and had to use a better shielded toenarm cable straight din to RCA onto the phono of preamp.
Grado's are notorious for the poor shielding of the cartridge, which in your case is picking up hum from the TT's motor. Used to be a problem for me until I got a TT with a well shielded motor. I've seen suggestions in the past for shielding motors. Perhaps some one will chime in with some suggestions.
hopefully someone will know how to shield the motor. I like the sound but hate the hum. The ply was way too "digital" for my tastes
try the mu metal shielding material
where does one obtain mu metal?
Is the motor on your Wilson turntable directly underneath the platter? What I have seen some do in the past is to place a thin sheet of aluminum foil underneath the turntable mat. This will create a shield in-between the cartridge and the EMF fields being created by the motor.

This is ineffective if the motor of off to the side. But if it is directly underneath, it may be an inexpensive way to create some shielding without breaking the bank.
Had the same experience with Grado's when I used them many years ago. I guess they still choose to not include shielding. I believe lead creates a good shield, but is obviously heavy. I wonder if you could address the shielding at the platter and or mat. There was a company called Merril that used to make mods for the classic AR turntables, one of which was a motor shield since those motors were unshielded and really did a number on the Grado's. The metal plate they sold to shield the motor attached to the plinth and did offer some improvement, but my Grado still had quite a bit of hum even with the plate. I also swapped out my motor with the Merril modded motor but don't recall that helping as much as the plate did. Otherwise I always liked the Grado cartridges. I had three as I recall, the best of which was in the signature series. All MM cartridges. On the same table I tried a Sumiko MM and got no hum at all.

Good luck!


PS A quick search on magnetic field shielding (MU shielding) turned up This Site. I'm sure you can find others.
woo hoo mu metal works.....thanks all
Hum on my the statment (when the arm moves closer to the motor) completely gone when ac motor was replaced by dc motor. Magnetic filds are night mare for grados. ph-1 is also very sensitive and did not like any heavy electric powers (transformers, wires) around.
Magnetic shielding is nothing like electric field shielding. In this case, it sounds liek magnetic. Aluminum foil will probably have no effect.

Sorry for error, I had in mind electric fields. However the Statement is dead quiet now.
Hey Tom,where are you?
This 'aint over ;)