Volcz
VCA '18
Join date: Oct 2011
2,428 IQ
#1
*AC30C2! Not the tube rectifier AC30CC2

Just came home today (after jamming with a sweet as orange rockerverb half-stack!) and fired up my AC30. But as soon as I started playing it was creating this crackling, fizzy noise. I was on the top boost channel maxxed out pre-amp volume. it also seems to have become a lot noisier (when not playing anything).

I tried changing guitars and cables and nothing seemed to fix it. I've tried turning it on and off as well.

I'm guessing this would be a tube problem? Pretty disappointing since this is a new AC30 I bought from Cranbourne Music about a week ago as a backup for my gigs and as a secondary amp for rehearsals.

I'll try post a video tomorrow morning.

Any ideas?
Quote by greeny23
i shake the walls of my bedroom. with mah dick.
Quote by Eppicurt
Quote by NakedInTheRain
hey, be nice to the hipster.
I hear they use false bypass switches.

It's, like, so ironic.
Last edited by Volcz at Oct 20, 2012,
jaybals
guitarchitect
Join date: Jul 2007
1,825 IQ
#2
I know Vox AC30's are renowned for chewing up tubes like warm toast, and Korg are notorious for selling them with bad stock tubes, so it's no surprise if they go bad. I had JJ's in my AC30's power amp, and tung sols anf RFT's in the pre
gumbilicious
beginner
Join date: Oct 2007
1,236 IQ
#3
Quote by Volcz
Just came home today (after jamming with a sweet as orange rockerverb half-stack!) and fired up my AC30. But as soon as I started playing it was creating this crackling, fizzy noise. I was on the top boost channel maxxed out pre-amp volume. it also seems to have become a lot noisier (when not playing anything).


well, if it is only on the top boost channel than it is most likely not the power tubes

Quote by Volcz
I tried changing guitars and cables and nothing seemed to fix it. I've tried turning it on and off as well.

I'm guessing this would be a tube problem?


it could be, but since it's a preamp tube it'd be pretty easy to troubleshoot the problem. you should probably have an couple extra preamp tubes anyway just for random problems. replace the preamp tubes one at a time and see which one is broke. you don't need to replace every preamp tube, just do this:
-pull V1 tube
-replace with the new tube
-check to see if problem persists
-if problem persists, then pull the new tube
-replace V1 with old tube
-repeat with the next tube

there is also plenty of chance that this is not a tube problem, this could also be a bad capacitor or resistor. if you don't wanna go for awhile without the amp, then troubleshoot the preamp tube, and if there is still a problem then send it into the seller to fix.
punk isn't dead, it's always smelled that way.

"A perfection of means, and confusion of aims, seems to be our main problem."
-ae
Volcz
VCA '18
Join date: Oct 2011
2,428 IQ
#4
Woke up this morning and it seems okay. The strangest thing I've realized is that theres volume coming out of the amp when you play, when the master volume is right off.
Quote by greeny23
i shake the walls of my bedroom. with mah dick.
Quote by Eppicurt
Quote by NakedInTheRain
hey, be nice to the hipster.
I hear they use false bypass switches.

It's, like, so ironic.
Alphaform
Registered User
Join date: Jul 2012
1,942 IQ
#5
does speakers breaking in make the amp louder??? just curious
R45VT
Doesn't speak guitar
Join date: Dec 2009
1,110 IQ
#6
Make sure a tube didn't just come loose. Happens in transport.
Quote by DeathByDestroyr
See, it's important that people clarify when they say "metal", because I pretty much always assume they are a Cannibal Corpse fanboi.
CodeMonk
UG's Old Fart
Join date: Apr 2004
1,581 IQ
#7
Stock, the AC30 tubes suck. IMO anyway.
I think mine had EH tubes.
Swapped them out for JJs and haven't had any problems since.
Not that I had any problems with the EH tubes. Just saying.

And what R45VT said, check for loose tubes.
gumbilicious
beginner
Join date: Oct 2007
1,236 IQ
#8
Quote by Volcz
Woke up this morning and it seems okay. The strangest thing I've realized is that theres volume coming out of the amp when you play, when the master volume is right off.


i don't believe the pot on the master knob doesn't provide an infinite resistance and that is why you may still get volume

Quote by Alphaform
does speakers breaking in make the amp louder??? just curious


maybe a little louder, as the parts will loosen, but i bet even the most experienced guitarists would be able to tell the difference in volume.
punk isn't dead, it's always smelled that way.

"A perfection of means, and confusion of aims, seems to be our main problem."
-ae
Alphaform
Registered User
Join date: Jul 2012
1,942 IQ
#9
Hmm okay
Last edited by Alphaform at Oct 20, 2012,
Volcz
VCA '18
Join date: Oct 2011
2,428 IQ
#10
I'm sending it back to the store as it's still covered by 14-day refund and warranty. Never had a problem with my other AC30.

Also I didn't bother to check the tubes if they were in tight because when I looked at the back panel, two screws were half-screwed in and I tried tightening them but they're stuck. 90% of the screws also have marks that make it look like someone has been tampering with the amp before I purchased it.
Quote by greeny23
i shake the walls of my bedroom. with mah dick.
Quote by Eppicurt
Quote by NakedInTheRain
hey, be nice to the hipster.
I hear they use false bypass switches.

It's, like, so ironic.
R45VT
Doesn't speak guitar
Join date: Dec 2009
1,110 IQ
#11
Good call. **** that turd. Hopefully they can get you one new out of the box.


I had a similar thing with my MKV when I bought it. Found a preamp tube shield in the bottom. Never fun when you spend that much dough.
Quote by DeathByDestroyr
See, it's important that people clarify when they say "metal", because I pretty much always assume they are a Cannibal Corpse fanboi.
Volcz
VCA '18
Join date: Oct 2011
2,428 IQ
#12
Quote by R45VT
Good call. **** that turd. Hopefully they can get you one new out of the box.


I had a similar thing with my MKV when I bought it. Found a preamp tube shield in the bottom. Never fun when you spend that much dough.


Yeah, 1.5k

Oh wow, from a Mesa? That'd be quite disappointing! I mean the Vox is built in China, so I guess I kind of am not entirely surprised - but for that much cash you know.
Quote by greeny23
i shake the walls of my bedroom. with mah dick.
Quote by Eppicurt
Quote by NakedInTheRain
hey, be nice to the hipster.
I hear they use false bypass switches.

It's, like, so ironic.
R45VT
Doesn't speak guitar
Join date: Dec 2009
1,110 IQ
#13
I bought it from GC. Once I found the preamp shield laying in the bottom I started looking And found a bunch more stuff.

I spent 2400.

Price shouldn't matter though. You would hope your brand new gear would be perfect. I expect some sort of QC either at the factory and/or point of sale.
Quote by DeathByDestroyr
See, it's important that people clarify when they say "metal", because I pretty much always assume they are a Cannibal Corpse fanboi.