Setting up a PA (Amp, speakers, mics)

lucid · 16 Sep 2013 at 18:11

It could be dying capacitors. They'll often work when warmed, but show as dead when cold. That might then have lead to problems for other parts of the circuitry. Transistors that are intermittent will work when cold, but as they warm up during use they'll fail. So you may have a combination of both issues if it isn't something external.

Peerzy · 16 Sep 2013 at 18:28

lucid said:
It could be dying capacitors. They'll often work when warmed, but show as dead when cold. That might then have lead to problems for other parts of the circuitry. Transistors that are intermittent will work when cold, but as they warm up during use they'll fail. So you may have a combination of both issues if it isn't something external.

Interesting - what could cause something like this? It's hardly been used and is only a few months old. Could it be the way I've wired the speakers up?

covenantuk · 17 Sep 2013 at 09:26

I have actually seen sports/village hall ceiling speakers wired up on a common ground, much like car speakers in the past, but that doesn't fit with the guy saying that the speakers were wired as you would expect.

Peerzy · 17 Sep 2013 at 18:13

Went back today and unplugged everything, turned it on and the protection light turns off after a second or two. Plugged the wireless mic unit back in and the same, plugged the laptop cable back in and the same. Added each speaker 1 by 1 and the light still goes off after 2 seconds. No idea if that means it's fixed but it was working when I left.

I'm waiting to hear if it has started cutting out again.

joeyjojo · 18 Sep 2013 at 13:58

Lakeland said:
It's hard to see but have you not flipped the switch to PHONO on Channel 6 in the first photo? I'm guessing that's why your laptop isn't working.

You don't want it set to phono with a laptop - far too hot. The images have gone now but if the alternative was "line" then that's the one to use for a laptop soundcard.