#1
Hello there

I have an old fender champ 12 amp and a little while ago it just stopped makings sound, although the light comes on and current still flows through the speaker, so thats not dead. I discovered that one of the valves wasnt lighting up, and so I'm replacing them, but I thought while I'm there I may aswell replace all the valves.

I bought the valves the other day, only to discover when i got them home that one is a 12AT7 and one is a 12AX7, im not sure of the difference, what will happen if i put them both in? Or will it blow the amp up or something? haha

Any help is appreciated.


I forgot to mention that they are electro harmonix valves, if that makes a difference.
"In modern music, a lot of people are really stuck on the example, asif it were the idea. It takes millions of examples to articulate an idea, so don't get stuck on the f*cking example." - Joshua Homme, 2008.
#2
The 12AT7 has a lower voltage gain than the 12AX7, but they are interchangable for the most part.

If the tube is for a vibrato circuit then I would make sure the 12ax7 is placed there, as a very high voltage gain is needed for the stage.
#3
Thanks for the reply man.

I just went for it and put them in there, sounds really good I'm really happy with it
"In modern music, a lot of people are really stuck on the example, asif it were the idea. It takes millions of examples to articulate an idea, so don't get stuck on the f*cking example." - Joshua Homme, 2008.
#4
http://www.guitaramplifierblueprinting.com/files/Phaseinverter.pdf

Here's an article on the Phase Inverter of a tube amp, and helps outline the difference in 12AX7's and 12AT7's too.
Then there's this band called Slice The Cake...

Bunch of faggots putting random riffs together and calling it "progressive" deathcore.
Stupid name.
Probably picked "for teh lulz"

Mod in UG's Official Gain Whores