Re: Hum has me stumped

Sorry to disappear on you guys. I thought the issue was resolved and
didn't expect further comments. Thanks to all who have contributed
helpfully. I think I've found the real cause of the problem.

I'll try to address the questions or suggestions you've offered:

Jeff Findley: My pre-amp doesn't have an unpolarized two pronged power
plug, so I can't plug it in flipped around. Also, all components are
attached to the same power strip.

normanstr...@xxxxxxxxxxx: I don't have a voltmeter, sorry.

windcrest: I don't have a power Y adaptor, but I'll buy one if others
think this is the best solution.

Richard Crowley: I noticed the hum a couple weeks ago.

AZ Nomad: A ha! By doing this, I isolated the new coax cable directly
connect to my tv as the cause of the hum. See reply to Pooh Bear below
for more info.

Pooh Bear: At first I thought I hadn't moved anything, but now I
realize that two weeks ago I signed up for cable to watch the World
Cup. I now have a splitter that goes to my cable modem and directly to
my tv. Disconnecting the coax cable from my tv kills the hum.

Any suggestions? Thanks again!


Jeff Findley wrote:
"johnelstad" <john@xxxxxxx> wrote in message
news:1150311946.800106.223710@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
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)

.

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