Stereo Amp Question

[HerrProctor]

So i had an old friend in town this past weekend, and I guess at some point he drunkenly knocked my stereo amp down on to the floor. He proceeded to complain about how bad my speakers sounded, even though he broke it and didn't tell me, but I digress. Anyways, what its basically doing is this:

The sound sort of fades up and down and every so often the left or right channel will partially cut then come back. This is the best interpretation I have of what it's doing, but I've never really heard anything like it. Some inputs work better than others, some barely produce sound at all. If i plug the inputs into some channels, it plays (crappily) selected on other channels as well as the one it should be set on. I took off the top and things look unbroken, there's no obvious damage. I didn't pay much for the thing, but any advice is much appriciated. If it requires repair I can't do, its in the dumpster.

[direwolf-pgh]

i know this wasn't a tube amp..cause your friend would be in the hospital right now.
solid state = stress fracture to the board (broken solder joints)

best shot in the dark. sorry buddy.

[Five]

its probably fucked but sometimes amps have a way of coming back to life for no apparent reason so don't throw it out right away.

if you're brave you can unplug it, open it up and look for any obviously broken connection and re-attach it with a little solder job.

also, I wouldn't send it to the landfill... just put it out side close to the sidewalk with a little piece of paper taped to it that says "free amp. needs a minor repair but still mostly working" and somebody will scoop it up.

and bitchslap your friend next time you see him.

[HerrProctor]

i already popped her open, i can't find anything unusual. im gonna slap him, he also broke my brother thelonious glass.

[splumer]

So i had an old friend in town this past weekend, and I guess at some point he drunkenly knocked my stereo amp down on to the floor. He proceeded to complain about how bad my speakers sounded, even though he broke it and didn't tell me, but I digress. Anyways, what its basically doing is this:

The sound sort of fades up and down and every so often the left or right channel will partially cut then come back. This is the best interpretation I have of what it's doing, but I've never really heard anything like it. Some inputs work better than others, some barely produce sound at all. If i plug the inputs into some channels, it plays (crappily) selected on other channels as well as the one it should be set on. I took off the top and things look unbroken, there's no obvious damage. I didn't pay much for the thing, but any advice is much appriciated. If it requires repair I can't do, its in the dumpster.

I'd make sure first that it is, in fact, the amp that was damaged and not any of the cables. I assume it was fully connected when it took a dive, so it may have yanked a cable or two on it's way to the floor. Check all those connections first, and then hook up your headphones to it and check to see how it sounds to narrow it down.

Another thing to think about it where did it land? Well, on the floor, obviously, but if it landed on any output jacks or control, those may be damaged. It doesn't take much to damage those. I work for an AV company and our gear, when it gets damaged, usually gets damaged in that way. For a board to break it's usually got to take quite a fall.

It might be worth it to take it somewhere and at least get an estimate for repairs, or maybe pay for a diagnosis and do the repairs yourself.

[Karst]

Alcohol and amps don't mix. Bring it to the closest pawnshop - someone will take it.

[direwolf-pgh]

nice amp for $10 bid
http://cgi.ebay.com/Vintage-80s-Harmon-Kardon-PM650-Integrated-Amplifier_W0QQitemZ130204915439QQcmdZViewItem?hash=item130204915439

[Five]

yeah, great amp ! I've got an h-k 590i (almost identical). the digitally-controlled tuner is a little wonky on mine, tho but excellent in every other way.

[mctom]

As already stated check all your connections first, were they still all connected when you opened it up?

[dorrcoq]

Bo knows amps