[loafier]

I have a hum problem on my system that's really starting to agrivate me. When my Bel Canto DAC and MPX3 amp are connected I hear a very audible hum noise, which I can't get to go away. This just started happening last night. I've never heard it before.

It's not the tubes or the MPX3 amp, because when I connect the amp directly to my computer sound card, the hum goes away. The Bel Canto is fine, too. When I connect it to a META amp, it is silent.

I've tried switching my DiMarzio MPath ICs to my old Outlaw PCAs and that didn't work either. Normally, both the Bel Canto and MPX3 are plugged into the filtered side of my Monster PC1000 powerstrip. I tried a different powerstrip and different outlets and that didnt work. I've also tried completely turning off my computer and monitor and network hub, the other devices hooked to the PC1000, and that failed. I'm using stock power cables.

Is there anything else I can try to fix the hum?

 

[tortie]

Try using a cheater plug, maybe its a ground loop problem.

 

[loafier]

Since I dont have a cheater plug, could I break off the ground pin on a power cable to test for a ground loop, or is that dangerous? If I understand correctly, a cheater plug cancels the ground, and has the same effect of removing the ground pin. Is that correct?

 

[Hirsch]

I would hesitate to float the ground on a tube amp. There's some serious voltage in there. Danger!

If you're going to try a cheater plug, you could try it on the Bel Canto, and see if it helps. It does sound like you've got a ground loop somewhere.

 

[qwerty870]

I agree sounds like a groundloop. I had a similar problem with my perpetual technologies DAC a while back. Deffinitely try and float the ground on the Bel Canto.

 

[loafier]

Well, removing ground on the Bel Canto fixed the problem right away. Thanks for the input, all. The amp remains grounded.