Marshall Amp Forum - View Single Post

Jesstaa · 06-28-2009, 09:21 PM

Quote:

Originally Posted by bjp

Thanks for your reply Jesstaa
The power transformer is vibrating slightly, I think I'm more aware of it, because I'm looking for faults and scrutinizing every part now. The power transformer has had a maximum use of 10 hours and was a fresh Marshall replacement which I purchased from a service tech who used to be our Marshall service agent. The output transformer appears to be perfect as, I said , I have checked it for shorts and readings of the taps seem to be right. Through out testing it remained cool, and the amp did sound good. I am aware that there is a hell of lot more to testing transformers than I have carried out, but I think they are good. Thanks for reassuring me though
, in the past I sold many Marshalls but it never occurred to me listen to the amps when they were just switched on, these amps being new I guess I never really looked for anything other than that the amp worked and sounded good. Many thanks for your reply. All the best

BJP

You say it was a proper Marshall replacement, meaning it was one of the transformers they fit into stock Marshalls? If you got it in 1991 and it was a new transformer, there is a good chance that even just the sitting around could've weakened it (The transformers Marshall has used in recent years have been dodgy from what I've been told). But you might wanna ask some experts, I'm not exactly a good source of knowledge, I just go off my experience and what people tell me, and then choose which seems most logical.

And remember, when checking a valve amp out, remember to listen to it, feel it and smell it. If the feel, sound or smell of it is a little odd, then it's most likely got something wrong with it.