Help me please my amp......

rainbow66666 · #1 02-24-2011, 06:40 AM

We had a gig last night and we were all sharing amps, so i brought my bass amp. The amp was working fine at the start turned the power supply on at the head and it powered the speakers fine and everything was nice. Then just as we go to do sound check the amp turns on (as usual) makes a quick pop sound (as usual) then hums quiet nicely (as usual) but when i put a lead in nothing came through no sound regardless of settings, we tried multiple leads and multiple basses but nothing. The amp sounds and looks like its functioning properly but isnt giving any sound from the basses. I already had the fuse replaced before cause the amp wasnt even turning on. But i dont know what it is. eletrical problem? I read somewhere that if the speakers are humming then there are still fine. If so then what the hell is wrong? anyone please

Downunderwonder · #2 02-24-2011, 07:56 AM

I dunno about the "speakers humming = hunky dory" school of diagnosis. On the face of it that indicates the power amp is running and there's nothing coming from the preamp. Could still be a dodgy speaker connection/lead.

I'd be looking at the input jack to see if it's all connected. After that you need an amp tech / someone that knows a lot more about amps than me.

You could try putting a signal in at the effects return if you have one. You'd need a "line" level signal there I think. So something juicy from an effects processor or another preamp.

JimmyM · #3 02-24-2011, 08:20 AM

it would be nice if we knew what amp it is, but since we don't, if it has effects loops that you don't use very often, they could have become corroded. so try running a plug in the effects loop jacks quickly several times and see if you can knock the corrosion loose. if not, then no idea.

WallBass · #4 02-24-2011, 08:26 AM

Was the volume on the bass up?
That's the best I can do.

rainbow66666 · #5 02-24-2011, 09:09 AM

cheers guys ya the amp has no effects loop, its just very basic with a gain knob, volume knob and an equalisation chart on it, opened it up and it looks completely fine from the inside so im guessing its got to be a problem with the wiring or speakers

dincz · #6 02-24-2011, 09:45 AM

Quote:

Originally Posted by rainbow66666

I read somewhere that if the speakers are humming then there are still fine.

So are they humming or not?

Bassman12350 · #7 02-24-2011, 10:11 AM

What type of amp is it, solid state or tube? There are a ton of things which could be wrong in either case, not just speaker cables. Probably time for an amp tech to check it out for you.

funkytoe · #8 02-24-2011, 11:54 AM

Check that fuse again. You say you replaced the fuse once before when the amp had no sound. Your amp could have a short and may be blowing fuses. Check it again.

Also, make sure all cables are connected properly and functioning. Did anyone substitute an instrument cable for the speaker cable between your head and cab?

I would change out my speaker cable (first) and if still no sound, my instrument cable (second) to eliminate cable failure as possible causes.

RickenBoogie · #9 02-24-2011, 12:02 PM

It would be nice to know what amp we're talking about, but either way, if you're not a qualified amp technician, then you need to find one and take the amp in for service. If it blew a fuse before, that means you have "other" problems, and now it's really in need of service.