"NGS" wrote in message
...
My guitar combo has five preamp tubes. They are all supposed to be
12AX7. For the effects send and return I use a 12AT7. For the first
preamp tube V1 I use a 5751. The last position V5 is the phase
splitter. What happens if I were to use a 5751 or 12AT7 or even 12AU7
in this position? Is it just the last boost stage prior to the power
tubes? Thanks.

There's a little gain... it also provides both sides of the push-pull
final section with drive.

Marshalls use 12AX7 here... Fenders use 12AT7. Try both and
see what you like, can't hurt.
__
Steve
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