#1
so my peavey 3120 isn't producing any sound whatsoever. no hum, no hiss, pops, notta. noticed my phase inverter preamp tube (it was a 12ax7, right next to my power tubes) wasn't glowing. replaced the tube, it's glowing now, but still no sound. all my other tubes are glowing just fine. no bright red color, no blue color..still no sound whatsoever.

went throught the following link to look for some answers

http://guitar.about.com/gi/o.htm?zi=1/XJ/Ya&zTi=1&sdn=guitar&cdn=hobbies&tm=2&f=10&tt=14&bt=1&bts=0&zu=http%3A//www.geofex.com/ampdbug/ampdebug.htm

somewhere in there he mentioned not to ttrust a new tube until it has some burning time. so should i just let my amp sit on standby for a few hours? are my power tubes going bad?

i've tried everything. switching cables, power supply cords, all kinds of stuff trying to get this thing to work. it was working just fine the last time i used it about a week ago at practice =(
keep writing. keep dreaming.

keep the notes coming...

ibanez ftw
#2
What have you been doing with your amp lately? Anything that could cause this?
Also, there should be a faint blue glow around the edges of your tubes. This is caused by the actual electron flow. The power switch will power up the grid (which will cause the filaments to glow), and the standby switch will make the outside of the tube housing glow a very faint blue. Without this, there shouldn't be any sound.
Standard Strat
Jackson WRMG
Parker DF724

Axe-Fx Standard
Carvin DCM1000L

Mesa Trad. Slant Recto 4x12 (UK V30s)
Custom Horiz. 2x12 (Commonwealth 12s)
#3
maybe because the PI tube went south, it caused the HT fuse to blow?
Call me "Shot".

ShotRod Guitar Works

Custom Hand-wired Amplifiers and Effect Pedals.

Est. 2007


Source to everything I say about Guitars, Pedals, and Amplifiers: I make them.


UG's Best DIY PedalBoard
#4
all i've been doing is using it at practice 3 times a week, and i've played 2 shows with it. all this since february.

i don't see any faint blue glow around the outside the tube housing.

and if the fuse blew, wouldn't my amp not even turn on?
keep writing. keep dreaming.

keep the notes coming...

ibanez ftw
#5
Correct, your fuse is not the problem. Any serious tube faults would cause it to blow. Which means good news and bad news.

Good news: Whatever problem your amp has isn't serious enough to the point where it will short your amp. (Yet)

Bad news: This may also make it harder to diagnose. Going by your description, you probably won't find capacitor guts spewed across the PCB, but it can be more of a problem than that seems. Unfortunately, no sound isn't better than shitty sound, and doesn't pinpoint any culprit. Specific sounds can hint at certain parts failing, but any number of items could cause a lack of sound. It could be the power supply, could be the speakers, could be power supply to the tubes specifically, your amp's probably class B so it could even be the output transformer. My advice would be to take it into a qualified tech who can take a solid look at it. No one here will be able to tell you exactly what the problem is without taking a look at the amp itself. Sorry to say.
Standard Strat
Jackson WRMG
Parker DF724

Axe-Fx Standard
Carvin DCM1000L

Mesa Trad. Slant Recto 4x12 (UK V30s)
Custom Horiz. 2x12 (Commonwealth 12s)