#1
My amp uses 5 EH 12AX7 preamp tubes.
If I were to put a JJ ECC83 in as the V1 tube, will that effect the gain channel tone?

wanting a richer distortion without changing all 5 tubes.
and v1 (closest to input) is the gain channel tube, yes?
#2
V1 is the input tube spot that affects the whole preamp. V2 is typically designated for the gain channel only.
You should hear a difference with the JJ in both spots. Try V1 first, then try it in V2.
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