#1
Hi!

My JCM800's tubes is probably dying (major loss of gain and it all sounds kind of shitty).
I opened it up today after leaving it unplugged for 2 weeks (I read that's the way to stay safe), and I could easily locate the power amp tubes, but I'm unsure of where the pre-amp tubes are.

Here are some pics:







Are the pre amp tubes inside the metal "cans" behind the blue thing?
Also, what power amp tubes to I currently have (I know they're el34's, but I don't know what brand).

I'm going to sell this amp, so that's why I need fresh tubes. I'm going to start out by chaning pre amp tubes since you don't have to bias those.

Also, obviously I'm a noob, so please bare with me.

Thanks in advance
Last edited by juliusxxrock at Oct 26, 2014,
#2
yes, the 3 silver 'cans' are covers for the preamp tubes.
I like analogue Solid State amps that make no effort to be "tube-like", and I'm proud of it...

...A little too proud, to be honest.
#3
Yea- in the first image the pre-amp tubes are the ones in the metal casings on the left side of the amp. In my amps, I just have to push them down a bit, then twist and they pop right up. Have you lost a lot of volume?
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#4
Yes. Those silver shields come off sorta like a childproof jar. Stick JJ ECC83S tubes in it.


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#5
Quote by Watterboy
Yea- in the first image the pre-amp tubes are the ones in the metal casings on the left side of the amp. In my amps, I just have to push them down a bit, then twist and they pop right up. Have you lost a lot of volume?

I can't say I've lost any volume at all, just gain basically.