"johnelstad" wrote in message
ups.com...
He shoots, he scores! My amp has a three-prong plug, so I added a
two-prong adapter and the hum disappeared completely. I'm so relieved.
Thanks so much, James, for your quick and helpful response!

John

James Lehman wrote:
Does you power amp have a two prong plug? If so try adding a wire from
the
chassis to a real Earth ground. If your power amp has a three prong plug,
try it with one of those two prog adapters with no ground at all.

Does your preamp have an unpolarized two pronged power plug? If so, I'd try
plugging the amp back in *without* the two-prong adapter and try reversing
the preamp's unpolarized power plug to see if that gets rid of the hum. If
it does get rid of the hum, then I'd keep it hooked up that way. Removing
the chassis ground on the amp by using a two-prong adapter isn't the safest
thing to do.

Also, as others have said, I'd make sure the preamp and amp are on the same
circuit. I'd do this by plugging all your audio components into a single
power strip/surge protector/line conditioner.

Jeff
--
"They that can give up essential liberty to obtain a
little temporary safety deserve neither liberty nor
safety"
- B. Franklin, Bartlett's Familiar Quotations (1919)