Tourmaster 4212 Tubes Question

[Len Rabinowitz]

Thinking about retubing my 4212, and maybe trying to save a few bucks, so a question:

Do the following pre-amp tubes just power certain functions, and hence not affect the tone (Meaning I don't have to replace them) or do they affect the sound somehow? What do the do exactly?

V5: Countour circuit buffers for overdrive channels
V6: Reverb drive and return
V7: Effects send buffer and effects return mixer
V8: Phase splitter, plus veggie juice (Just seeing if you are paying attention!)

Thanks!

 

[Rod]

Hi...The Contour tube only works if you use the contour control and turn it on. I don't use it, so it's an xtra tube for me if another one goes south at a gig...The reverb and FX only affect the said stuff, not the tone of the amp....The phase inverter definetely affects the tone.....put in a good matched triode JJ if you can,,,not the 803, but the Ecc83....and V1 affects the tone of all the channels...V2 is ch 3 and 4. V3 is 2 and 3. V4 is only ch 4.....After owning and playing out with my Tourmaster for over a year, I just spent the last week retubing all the preamps tubes...Trying different brands to see if there's much difference..messing more with the FX loop...[still sounds best in the serial mode with my pedal delays and reverbs.].....The main thing to watch out for is microphonic tubes...Bruce's design pushes these tubes into some great Overdrive, but that can be touchy if you have any tubes that are microphonic....and sometimes a microphonic V1 won't show up as an issue till you hit channel 4...So at any rate, I'm using some JJ's, Electro Harmonix, Russian 12AX7's, a Mullard, and an RFT. hope this has been some help....rod