Buzz/hum from Spectron Musician II amplifier.

If it's a transformer hum, you need to check your voltage. My voltage ramps up to 129volts and made my balanced conditioners transformer humm. It doesn't sound like a ground issue.. Also sometimes in shipping the transformer mount loosens up inside and it might need to be tightened down, but if your sub is doing the same thing you have a problem in the power.

Thanksfully 10" away isn't bad though..

Panamax conditioners won't help.. you need a regenerator (PS Audio Powerplant, etc.) that might help if it's a voltage problem. Take the amp to a friends house and measure his voltage and see if the amp humms.

Thanks - this seems to be the consensus in the cross post as well. I am going to take the amp to another house and see what happens, and see if I can diagnose the voltage, as well.

I would second the hypothesis that the voltage ramp up causes the hum. I've had a Spectron Musician IIISE in my house for about a week and a half, and it sometimes hums (the unit, not through the speakers)...but it's always been around 5-5:30 in the morning...never in the afternoon or evening. Come to think of it, kind of fits the same scenario with some Blue Circle Noise Hounds I have.

Problem was completely solved with a Channel Islands Audio XDC-2 AC filter. definitely transformer hum from DC noise riding on the eAC line.

Just the other day, I received my Musician II that has been recently upgraded to a Musician II Hybrid. There was a significant and new hum similar to what you've described... mostly heard about 10" away, but also noticeable from the seat during some quiet passages.

Based on what was said in this thread, I tried an experiment: Normally I plug my amp into the "Filtered AC" plug on my PS Audio P500 regenerator. This connection doesn't regenerate the AC, but presumably has some sort of filtering... clearly not enough to knock down the hum. I plugged the amp into the "regenerated" outlet, and the hum stopped.

I suppose that this supports the DC noise theory.

Problem is, as I understand it, one is not supposed to use regenerated AC ports for the amp, lest I restrict the power. Thoughts? (I'm planning to contact PS Audio for their opinion.)

My P500 also has a slight bit of hum. Do you suppose that the Channel Islands XDC-2 would work between the wall and the P500, knocking out hum for all the gear?

Rob