#1
I just got a new amp yesterday. It sounded great. I have played it probably six or seven times and everything was fine, until..... I was plugged into the Top Boost channel and switched to the Normal channel and there is a terrible noise that sounds like static from a radio that gets louder when I play a note. There is also a hum that stops when I put my hand over one of the pickups. Is there a problem with my amp or a problem with the wiring in my guitar?
MY GEAR

Guitars
- Gibson SG Standard(Ebony)
Amps
- Vox AC30
Pedals
- Vox V487A Wah
- SansAmp Classic
- EHX Big Muff Pi w/ Tone Wicker
- MadeByMike Custom Overdrive
- HBE Germania 44
#2
My initial guess is that you have a microphonic preamp tube. They are easy to replace. I'd buy 1 or 2 from one of the online tube dealers. Tung Sol is a good brand.

dougstubes.com
thetubestore.com
tubedepot.com
eurotubes.com
hotrox.uk

also try your guitar in another amp so you can rule that out.

report back
#3
Quote by 311ZOSOVHJH
My initial guess is that you have a microphonic preamp tube. They are easy to replace. I'd buy 1 or 2 from one of the online tube dealers. Tung Sol is a good brand.

dougstubes.com
thetubestore.com
tubedepot.com
eurotubes.com
hotrox.uk

also try your guitar in another amp so you can rule that out.

report back


I only have one guitar and one amp... with no access to others....
MY GEAR

Guitars
- Gibson SG Standard(Ebony)
Amps
- Vox AC30
Pedals
- Vox V487A Wah
- SansAmp Classic
- EHX Big Muff Pi w/ Tone Wicker
- MadeByMike Custom Overdrive
- HBE Germania 44
#4
I would just take it back and get another one instead of replacing tubes as soon as you get it.
#6
Quote by Kyleisthename
I would just take it back and get another one instead of replacing tubes as soon as you get it.


Bought it off a guy on craigslist.
MY GEAR

Guitars
- Gibson SG Standard(Ebony)
Amps
- Vox AC30
Pedals
- Vox V487A Wah
- SansAmp Classic
- EHX Big Muff Pi w/ Tone Wicker
- MadeByMike Custom Overdrive
- HBE Germania 44
#7
Quote by Darkflame
^he bought it used
I agree with the toob change =) tap on your tubes with a pencil's eraser tip to see if one of them makes a bigger pop than the others, that would be the microphonic one


Its an AC30, so this may sound dumb, but am I going to have to take apart my amp to get to the tubes.
MY GEAR

Guitars
- Gibson SG Standard(Ebony)
Amps
- Vox AC30
Pedals
- Vox V487A Wah
- SansAmp Classic
- EHX Big Muff Pi w/ Tone Wicker
- MadeByMike Custom Overdrive
- HBE Germania 44
#10
Quote by mmolteratx
No. They stick out of the chassis.


The only part of the guts I can see are through the 3 grill things on the top.
MY GEAR

Guitars
- Gibson SG Standard(Ebony)
Amps
- Vox AC30
Pedals
- Vox V487A Wah
- SansAmp Classic
- EHX Big Muff Pi w/ Tone Wicker
- MadeByMike Custom Overdrive
- HBE Germania 44
#11
You can feel them by sticking your hand underneath the slot in the back. For easier access you could take the top part of the back off but that's no effort whatsoever. Just make sure not to touch the insides.
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