could one of these separate units substitute the regular pre-amp section of a regular all-in-one, standard-style amp?
I'm specifically refering to a 2 channel mesa.
is their v-twin a stand-alone pre-amp? or is it a regular pedal?
if its possible to do this, what brand/model, high-gain pre-amp might you recommend?
um bit unclear on what ya meant mate, but if ya lookin to use different sections of an amp exclusivly you use the effects loop. turn the effects loop to full and put a lead from your chosen preamp to the 'return' section of the effects loop.

probs no help but cya

actually, that's exactly the answer i was looking for
now, which pre-amp brand/models could you recommend for high-gain. can units like the mesa v-twin, a pedal-style pre-amp, replace the the built-in pre-amp? or will only the rack units do the job?
the Vtwin actually has a rackmount version in addition to the pedal, but they are the same unit. The pedal has a seperate output designed specifically for running into a poweramp, or the FX return in your case. I've owned it and used it this way with a combo amp.
"The fool doth think he is wise, but the wiseman knows himself to be a fool." - W.S.
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unfortunately the v-twin is no longer in production. could you recommend another brand around the same price?
you can find them used pretty easy, they are a hardy little unit too. The foot pedal is built like a tank, I know from taking it apart, lol. TBH though, I found it to be a little loose with it's gain, kind of got fuzzy too.

Going to be hard to get something for the same price though, I've seen them used under $250. What kinds of tones are you looking for, and what's actual budget? The ADA MP-1, Mesa quad, maybe an ENGL E530 pre are all pretty well regarded, and pretty reasonably priced if you go used.
"The fool doth think he is wise, but the wiseman knows himself to be a fool." - W.S.
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