I have an old Adcom amp that I use in my keyboard rig and like it. Lately, it developed a buzz that comes and goes (it stops after 1/2 hour or so of operation). The buzz is not coming through the speakers, but a physical, 60Hz vibration. I suspect it is a transformer.
So, how do I stop it? Hot glue (will that melt when the amp is hot?)? Jam a piece of something under it to wedge it?
It operates fine. A few years ago, I upgraded the power supply with a kit from some guy on the internet. I soldered it up and installed it fine. I am not sure if this is the section of the amp that is buzzing as I have not opened the thing yet. I will do it in the next day or so, but I want to be prepared to repair it before I open it.
Ideas for stopping the buzz? Ideas for diagnosing? Since it is a physical vibration, I figured I would just pull the cover and use my ears and a non-conductive poker to find the offender.
Thanx man… that is all that it was. Actually I don’t think the screws moved, but I think there is a rubber pad or some insulator under this huge toroidal transformer and maybe it is breaking down over the years?? maybe?
I dunno, I did tighten up the four corners and it apparently worked.
Nice call, Elk. Hang on to that Adcom amp, Bruce. It’s good for another 20 years. Adcom was my introduction to high power SS amplification. Built like a tank.
Apparently, according to those tech illuminati of the internet, this amp had a less than perfect power supply. So there are kits out there and I soldered one up… and I did a three-prong plug… cheap fun. Interesting that this amp still has a following after all these years.
I never put this amp in my big home audio rig so I am not real sure how it sounds… You would thing a geek like me would have tried it out but I guess I just don’t like all that work. For my keyboard setup, it sounds really good.
Every got-dang amp and component has a less-than-ideal power supply. And Caps. And Input transformers or Output transformers. And/Or overall design. Not to mention Parts Budget.
But have to say that the Adcoms weren’t some Lost Holy Grail. They were generally good. Mostly didn’t suck. Which is - surprisingly - saying something.