Crate GFX 212T amp sound cuts out
The sound cuts out on my Crate GFX 212t but returns with pressure on any control knob or bumping the amp. I'm thinking loose solder joint but not sure where to start.
It sounds like a bad solder joint or a loose connector. If you are comfortable removing the amp from the case, first look for any lose connectors (AC unplugged). If none are found then plug in the amp into AC and use a plastic handle of a screw driver (or other plastic device) to tap around the circuit board. With the volume set a a low setting, the place that makes the loudest static with light taping is usually close to the problem area. Unplug the amp from AC and carefully look for a bad solder joint. You will need a soldering iron and solder to fix.
Chances are you input jack is breaking free from the solder holding it to the board. Unplug Amp and then speakers, Use philips head to remove amp head. Also unscrew the knobs and nuts securing Potentiometers and 1/4” Jacks. Once you have the amp head separated safely then analyze input jack. Suction and or whick the old solder off. Use soldering iron and solder of your choice to resecure the input jack to board. (You can even skip the desolder part and just hit the joints with a fresh bit of solder). While the amp is open go ahead and resolder any other solders, but more importantly you can also get some contact spray and spray all the potentiometers while turning the knob to clean out any residue. If your volume or gain pot (or others) are dirty it can be responsible for connectivity issues.
after that verify that the speaker cable going to the amp board look good. Then reassemble, be sure contact spray has dried, and then plug in and play (hopefully it sounds new again).