What causes a loud hum from an amp? really loud

[danger boy]

Without any speaker hooked up the amp.. it hums, but not to loud.. of course hooking up the speakers magnifies that hum.. i cleaned the connectors with DeOxit and it didn't help. so something must be bad... like a cap or something.

any ideas?

[zarrdoss]

uasually caps going out, is it a Carver?

[danger boy]

ok.. but no it's a Marantz mono block.

[zarrdoss]

about how old is it? I have a Carver doing the same thing.

[danger boy]

about 15 yrs old. i'm not the original owner of course. these things are pretty inexpensive if I can't find someone to fix it.

send your Carver amp to Bob (Carver) himself. I hear he work's on gear still ;)

[lightman1]

Once more, Al....strategic placement of a ball-peen hammer.:D

Could be a loose ground.... chassis, power supply TX.....given the age of it.
Or you could "re-boot" it.

[zarrdoss]

There is a repair shop around the corner from me that I dropped it off at a few weeks ago and if has has not had a chance to look at it I will send it in to Bob instead, On yours, just for someone to look at it is about $30-$40 and if its a cap anywhere from 100-150 at least thats what I got on mine and I see those mono blocks all the time for $150 or so on CL. You might try ben, Good luck!

[NewHTguy]

I have a very low-level "mechanical hum" with my Parasound even when it is not connected to anything bu the ac outlet. You can't hear from a few feet away, but it is one of those things that irks me just knowing it is there. Seems to be fairly common, so much so that Parasound does not have any official definition for "defective" when it comes to mechanical hums.

[PSOVLSK]

My xpa-5 does this. The buzz/hiss is in the amp itself, but it also comes through the speakers. As NewHTguy said, I can't hear it from a few feet away, but it still annoys me.

[Ricardo]

If coming from the amp, probably a mechanical hum from the toroidal. There are several threads on this if you search. Could be DC current in your power, loose toroidal, or just a toroidal that will hum (loose wiring maybe?).

[danger boy]

turned out to be a crack in the circuit board. not sure how that happen. had the amp for two years.. no problems. then all of a sudden a crack appears in the board? Odd.

fixed now.. $60 and she's happy again. :)

[danger boy]

Once more, Al....strategic placement of a ball-peen hammer.:D

Could be a loose ground.... chassis, power supply TX.....given the age of it.
Or you could "re-boot" it.

that would have been my next avenue. LOL

a ball peen hammer could take care of a lot of my problems.. both stereo and people wise. ;) :p

[lightman1]

that would have been my next avenue. LOL

a ball peen hammer could take care of a lot of my problems.. both stereo and people wise. ;) :p
Good stuff Buddy:D
Glad you found the problem. Sounding better now?

[tonyb]

Maybe that amp was crying out to be replaced with the MF super chargers.Glad your up and running.