Speaker output jack is dead-Warning Noobie Alert

[HackRabbit]

I am a Noobie. javascript:emoticon(':shock:')
Long time lurker, first time poster.

I have a Roland Jazz Chorus 120 head.
If I plug into one of the speaker output jacks, there is no sound at at all. No click, no nothing. I can plug into the 3 other speaker jacks and they work fine, so I don't think it is a cable/speaker issue.

My technical level is very low, I have soldered guitar circuitry, but I have never been inside an amp. Is it dark in there?

On a related note, do solid state amps retain fatal charges when not plug in like tube amps?

There are 2 jacks per channel, so I can use the other one, but I would like to correct this defect. [I want to sell the amp to help finance an Express build ... and then and only then will I be truly happy. javascript:emoticon(':lol:')]

[M Fowler]

If it is the jack that you use the most then more than likely the PCB tracing is broke and maybe able to be fixed by jumpering to a good part of the tracing hard to tell until you get into the dark spaces and look.

It is safe to look.

Mark

[Structo]

Yes on a lot of printed circuit board (pcb) amps, they solder the jacks right to the pcb.

What happens is that when the jack is used a lot or the plug gets bumped when plugged in the little lugs on the jacks can break loose or pull the trace off the board.

Pull the chassis out and take a look. You may be able to fix it just by touching up the solder there.

[M Fowler]

Yes about 1 year ago I thought my transformer for my Roland GR33 had gone bad so I paid big bucks for a replacement from Roland and guess what it was the freakin DC power jack not the transformer.

I opened the GR33 up to find a huge amount of tracing floating and then had to solder it back down and so far it has held onto the remaining tracing but it won't last much longer gigging. I will then need to find a new path on the PCB as I am not throwing away a well used GR33 away just because the PCB tracing is bad, too expensive of a machine.

Mark

[HackRabbit]

Tom Mark
Thank you for taking the time to reply.
I will take a look under the covers to see if I can really munge things up.
Peter

[Kregg]

It's probably just a loose solder joint. If you don't have experience with amp repairs, you're better off having an amp tech take a look at it.
That said, if you have a total of 4 jacks (2 right/2 left) just choose between the remaining working channels and go with it.