Help! Amp is humming!

[admin_exported]

Hello guys,

My vintage Marantz PM40se has a very annoying hum. It comes through the speakers and is not dependent on the volume or source. It stays when I decouple everything except the speakers. It's not always there, and I can stop it, by (don't laugh) sqeezing the front and bottomplate of the amp a certain way. It's absolutely silent then. After a while however it always returns. Anyone knows what to do about this? Thanks!

 

[PJPro]

Jack White:
... I can stop it, by (don't laugh) sqeezing the front and bottomplate of the amp a certain way......

Sounds like a job for the Mrs?

 

[a91gti]

I think your transformer may be on the way out, I had a humming Quad 303 that responded well to a sharp rap on the top and a new transformer fixed it.

 

[tonky]

Does it not know the words?

 

[Anonymous]

If squeezing the front and bottom plate together helps sometimes have you tried tightening all the screws to see if that helps at all. The screws on my amp seemed to loosen a bit after about one and a half years usage. I tightened them up the other day.

 

[Anonymous]

Thanks for your reactions (well, some of them were helpful...). I've tried tightening the screws, but that does not help. If all else fails, I will replace the transformer, but I would like to exclude other (cheaper) options first.

 

[PJPro]

Tightening the screws might not seem as silly a solution as it first appears. Most amps, etc will have earth connections attached to the case and rely on good contact between the panels to ensure continuity.