#1
Hey, I just picked up a used Marshall AS50D Acoustic Amp. Some dudes were cleaning out their warehouse and said I could have it. When I turn it on it hums even if all the knobs are at 0 and there's no output when I play the guitar(which is known good)

The power rating for this amp: 130 watts(not to be confused with the output which is 50 watts) 120 Volts 60 HZ

Here's what I checked... I checked the fuse on the circuitboard. I checked for continuity through the fuse and it checked out fine. The only discrepancy I could see is that on the circuit board it says that for the 120V version a 1.6 Amp fuse is required and the fuse that's in it is a 1.5. Will that cause the amp to hum like that? I would have gone right out and gotten one but I'm in Iraq, I doubt they have 1.6 Amp fuses over here.

I checked all the wires and none were loose. I replaced the speakers with a known good speaker and it still hummed.

I checked the voltage at the power cable and it is indeed getting 110 volts and there's also voltage going to the fuse clips.

I checked the ground wires and they're firmly attached and there isn't a smell of burnt electronics or any burn marks on the circuit board.

Any help would greatly appreciated. Thanks...
I PAY FOR MY MUSIC!!!
#4
asshole.... way to spam my thread you jackass!

It's a three prong. would you normally still have some output with a ground loop hum?
I PAY FOR MY MUSIC!!!
#5
Quote by paesano
asshole.... way to spam my thread you jackass!

It's a three prong. would you normally still have some output with a ground loop hum?

haha just try a different outlet, even though it is a 3-prong.

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#6
I took care of the advertising, but don't bump your thread, please.
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#7
Quote by jc349
haha just try a different outlet, even though it is a 3-prong.


Ok, tried a few other power converters. I'm overseas right now so there is no actual 110v outlets, we have to use step downs. The only reason I wasn't immediately ready to accept that explaination was because my other 110v amps (frontman +vypyr) work just fine out here. I think it'll just sit in storage until I get back and I'll take it to a shop. I got it for free so I'm not complaining. Appreciate the help...
I PAY FOR MY MUSIC!!!