De-barring a Power Amp

How do you clean a power amplifier.  Here are some responses from the SynAudCon forum.

Tips from the He(a)rd

I have a question about cleaning a power amplifier. We recently acquired an amp from a private source that has obviously spent most of its life in a bar, as it has a strong smell of cigarettes. We plan to use it as a rental and loan unit, but as most of our clients are churches, we can’t use it smelling as it does. Will it hurt the unit if I let it soak entirely submersed in a tub of hot soapy water for a while and then give it a thorough but gentle scrubbing, followed by a drying out with the heat gun? Any other suggestions for cleaning it? Normally I would just blow it out with compressed air, but the limited amount of dust that is inside is sticking to the surfaces. Thanks.

Dave Wettlaufer

I’ve never done this with a power amplifier, and I was less than a willing participant (less than a believing participant?) when we used a car wash (yes a car wash) to clean a console that had clearly been through the works. The chief engineer had read something in Broadcast Engineering about this solution, even dug out the issue and let me read it when I questioned his sanity.

I’m a believer now… We did remove all the faders (they weren’t sealed), and we did disassemble it before washing it, but it worked, and looked as good as new when we finished. Amazing I tell you…

Bill Thompson

Go for it. I would recommend “Purple Power.” It’s a cleaner/degreaser that is a solvent to nicotine and whatever other nightclub sin residue is over your amp. You can buy it at Home Cheapo, etc. I dilute it about 10:1 with water. Put it in a spray bottle, spray down the amp and rinse. You will see a stream of mud come rinsing out of the amp.

Get as much water out as you can with an air compressor, especially around inductors, under chips, behind boards, etc. Let it further dry out for a day before you power it up.

I know it sounds kind of barbaric, but the only thing I ever killed with this method was a muffin fan in a light fixture.

My contemporaries gasp when they see me hosing down the guts of a 4500 lumen video projector, but they marvel at the image quality improvement once all the bar muck is cleaned out.

Dave Rosenbloom

I can remember Fred Fredericks of TOA telling me they would often put cruddy circuit boards in the dishwasher (low heat).

Pat Brown

When I was working at Crown in 1971 we had a fire that destroyed the plant. We were able to salvage some of the amplifiers for personnel use and in the plant. We washed the units in soapy water and dried them in an oven at 150 degrees. It is important to get the water out of the transformers. The car wash trick sounds as good as anything and then dry it in a warm place or oven.

Don Eger