Rocker 30 Preamp tube configuration

[jvolz]

If anyone could clarify which socket is v1, v2, and v3 (phase inverter) it would be greatly appreciated! Thanks!

[jerem37]

The preamp valves are labelled V1, V2 and V3 in this pic:



(Apologies to notagain for borrowing the pic...) Smile

(Sorry also for going back to basics here if you know preamp valves 1.01 already. Some reading this may not though...)

Each preamp valve has two separate halves and is effectively two valves in one bottle. They are totally separate and can be working in totally different parts of an amps circuitry.

The 'Natural' channel just uses one half of the V1 valve for its gain stage.

The 'Dirty' channel uses the other half of V1 and both halves of V2 for its three gain stages.

V3 is called the 'phase inverter' (PI) valve. Technically it is really more part of the power amp than the preamp. Signals from both channels go via it to the power stage.

So changing V3 (the PI) will affect the sound of the whole amp. (Want the whole amp brighter for example? A brighter sounding valve there will do it.) Changing V2 will only affect the sound of the dirty channel. Changing V1 will affect both natural and dirty channels, but differently from V3 as V1 has gain stages.

Pull V2 and the 'Natural' channel still works fine but you'll get nothing through the dirty channel. Pull either V1 or V3 and (for different reasons) you'll get no signal through either channel.

Knowing that upinflames, if you are basically happy with the sound of the dirty channel you only want to swap out V1. (You're inevitably going to change the sound / feel of both channels, but thats life. If it changes the dirty channel tone / gain some you can alway reset the controls on that channel a bit to compensate.)

Hello,
I asked same question few month ago, and Andy H. gave me this answer.
Thanks to him again.

PS: it would have been better to ask your question in the "technical" part of the forum i think...

[jord123]

so, I am looking at wrangling in the volume of my dirty channel, I going to put an at7 in v2. i'll get back to you I currently have jj's in all three slots, what do you suggest to brighten up the amp?

[jord123]

just put a new at7(ecc81) in the v2 slot. cool change, less gain, more tone. still pretty loud, I'm gonna mess w/ it tonight and try it in v1 tommarrow. i