sunn PA problems

[LOWBOY]

i have an annoying little problem i was wondering if anyone here might give me a little insight.

i have a 4 channel SUNN sx4150 pa plugged into a pair of peavey 115DL cabs.

usually its running either 4 mic's

(a fender D3 a GAS and a couple of shures)

or 2 mic's a keyboard and a yamahahaha drum machine.

 

the problem is every now and then the volume fades out.

turning the knobs doesnt seem to do anything,

but tapping on a mic will usually pop it back on

i know what ever is wrong is something in the output stage because everything cuts out.

the strange thing is,if its being used for a few hours everyday its not a problem.

but if its only being used once or twice a week then the problem returns.

lateley i turn it on an hour or so before band practice because it does fuck up less when its hot

but its just a pain in the ass.

anyone have a clue what the problem might be?

i dont have the $$$ to take it to a tech for a checkup at the moment.

so i dont know if i should stop using it for now or just live with the annoyance and hope nothing bad happens.

it would be nice to be able to use my pa for partys and gigs and nothave to worry about it.

[Bill Roberts]

Bad capacitors.

 

It is either the power supply caps or the input caps.

 

How do I know this???

 

 

Well, I have been there.

 

Any good guitar amp service person can do this easy..and not expensive. Expect around 60 labor and the caps.

 

Of course, I could be wrong...but I am willing to gamble a free song of my mastering on it.

[philbo_Tangent]

Try resoldering all the joints.

 

If it's really *fading* out (not cutting out) your capacitors are probably fine. More likely an intermittent open circuit in the power supply, IMHO.