#1
I was able to afford a Vox AC30 (one of the new Custom Classic models) back in December and it has been running fine since, but today I had it on with my SG plugged in and it started to crackle (I didn't touch any of the controls). For some reason it seems to be louder (even turning the Master Volume and Normal Volume down to 0 still gives a very loud level of sound). It also seems to be humming alot more. There's no problem with the grounding of my guitar as I'm still getting the same noise when unplugged.

Has anyone else had this problem? Could one of the tubes possibly be damaged or is it a grounding issue in the amp?
#2
Is the amp plugged into the same socket it was before? I heard that using one of those power strip things causes some background hum.

As far as the crackling, that could just be a dodgy cable or jack. Check to make sure the output jack on the guitar isn't damaged and try a couple of different cables if possible. It could be the input jack on the amp as well so check that if you can.

The volume swells could be caused by a dodgy volume knob or something like that. I don't think the valves are on the way out though. Failing power valves tend to result in a volume drop rather than an increase and I dont think that would cause any crackling anyway. I'm not an expert but hope I helped some.
#3
Quote by Snake_42
Is the amp plugged into the same socket it was before? I heard that using one of those power strip things causes some background hum.

As far as the crackling, that could just be a dodgy cable or jack. Check to make sure the output jack on the guitar isn't damaged and try a couple of different cables if possible. It could be the input jack on the amp as well so check that if you can.

The volume swells could be caused by a dodgy volume knob or something like that. I don't think the valves are on the way out though. Failing power valves tend to result in a volume drop rather than an increase and I dont think that would cause any crackling anyway. I'm not an expert but hope I helped some.


Yes it is. I then moved it to see if there was any electrical interference. It really is quite odd. I can't get that same warmth out of it anymore, it seems to have lost its thicker tone and seems much louder. I tried a different amp cable and it didn't make a difference, the amp is humming (even when not on standby). Thanks for your help.
#4
That's typical of a bad solder joint around a pot (probably the grounding side). Happens a lot...bad solder joint gets vibrated apart during use. Take it to a tech.
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#5
Quote by DLrocket89
That's typical of a bad solder joint around a pot (probably the grounding side). Happens a lot...bad solder joint gets vibrated apart during use. Take it to a tech.

Yeah, that sounds like the most logical explanation. It just seems to have lost its sustain and control over its volume. Its got too much hum.

Is this an expensive problem to fix? (Being a tube amp and all).

Thanks for your reply.
#6
Quote by Sticky Piston
Yeah, that sounds like the most logical explanation. It just seems to have lost its sustain and control over its volume. Its got too much hum.

Is this an expensive problem to fix? (Being a tube amp and all).

Thanks for your reply.


depends on amp tech. should be about a couple hour job (disassembly and reassembly are total pains...
Quote by kcdakrt
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