Centaur Keyboard Amp Needs Help!

[nitekatt2009]

Hi. I am a pro keyboard player and my ole trusty Centaur KB amp has failed. It has a 12" PS Carvin speaker and a Motorola 1" tweeter and is solid state. The amp hums, buzzes, static, you name it. I would like to try and troubleshoot it myself and even restore and overhaul it. It's too old to send to the shop and pay hundreds of dollars to fix. I took out the 12 and tweeter and they were hooked up to the wires ok. Didn't see or smell any burnt caps, resisters, etc. All solder connections seem ok/

Where do I start as a beginner? What tools do I need and books? Also, I want to learn as a hobby, troubleshoot and work on all my keyboards, pedals, everything that is out of warranty. I want to build some kits like a preamp, but want to start at the basics.

Yesterday I went to Frys and bought a ECG 25 watt soldering iron, an EDSYN universal, holder some regular rolled up solder, some 9 volt batteries. I bought a portable multimeter at Radio Shack that was about $30. Yeah I know, whoo, big purchase, heheh. Anyway...

Frys has oscilloscopes from $200 up to $4000, yikes. They also had power supplies and other interesting expensive electronic toys.

Anyway, I'm the grasshopper now, so I'm hoping a master here will offer me some advice and help send me what direction to go and what kind of gear do I need. I also got a PDF of Jack Darr's Amp book, but it mainly involves tube amp repairs which is good.

If I am in the wrong forum here, this is my first post since I joined this morning and glad I found it. So much good info and pros here.

Thanks for your help and response. katt

[Enzo]

Oscilloscopes are great, and maybe the most powerful diagnostic tool on the bench. But until you know what you are looking at, there is little point in getting one. You want to learn to work on amps, but you'd have to learn to operate a scope as well. Not to mention learn what a meter is telling you. By all means learn this stuff, we help people every day do just that, but it is not simple like show me how to play solitaire.

DO find some sort of kit to build, that will teach you to solder and deal with parts. Also, when you make a mistake, it is not on your primary equipment, it is on your little kit.

To actually approach your amp, we would want a schematic. I am not personally familiar with that amp. If it were in my shop, I might not need a schematic, because I have many years experience in such repairs. But I cannot direct you to things we have no means to locate.

Off hand I would suspect you have cracked solder connections on the main filter caps, and possibly the jacks and controls along the panel. Not to mention the controls likely need cleaning.