Solid State Guitar Amp Forum | DIY Guitar Amplifiers

So my friend gave me an amp to fix. As mentioned its the DXB112, a simple 30W combo from crate. 

It turns on, all the lights turn on and the switches react to being pressed but there is no output. I checked for shorts in the input and output and for loose connections. The main power amplifier seemed to be ok. No shorts across certain pins. There is a pop when the amp is turned on and then a pop a few seconds after the power is turned off.

I have some moderate experience with debugging, but am not sure where to take this one.

http://www.crateamps.com/pdf/manuals/DX112212_OM.pdf (http://www.crateamps.com/pdf/manuals/DX112212_OM.pdf)

Thanks for the help in advance.

Could be a bad solder somewhere.  Is there any sound if you plug headphones in the headphone jack?  What about if you jiggle the amp while it is on, any noises?  Drop it from 1-2 inches, any noise out of the speaker?

Simple? no way!!
It's a very complex digital beast, that just happens to have a 30W power amp.
If you have a (reasonable) pop when on and off, probably the power amp is fine; but if the digital part is bad, or simply acting stupid .....  xP
Can't even suggest the traditional "check the effects loop", because it doesn't have any.
Do you get sound through the stereo line in?
Worst case, you have a powered box, similar to Trade60 extension cabinets, and can drive it straight from a Pod or pedalboard.

Sorry i guess i misspoke. Well i did get some output from the line in but it popped a fair amount and only after I pushed the jack in relatively hard. I can't seem to find my quarter inch to headphone jack adapter so ill go get on of those today.

Ill be working on this later in the week. Got classes to work on.

Thanks for the help.

Quote from: Ullr on March 29, 2011, 01:23:59 PM
Sorry i guess i misspoke. Well i did get some output from the line in but it popped a fair amount and only after I pushed the jack in relatively hard. I can't seem to find my quarter inch to headphone jack adapter so ill go get on of those today.

Ill be working on this later in the week. Got classes to work on.

Thanks for the help.

Sounds like you might have a bad jack or solder going to it.