happyruss wrote:
I have a question about tube swapping....

In my Hammond organ, I recently replaced two Yugoslavian 12ax7e tubes with a
pair of RCA 12ax7 tubes (for the sound).

My question is this:
Can I replace the 12au7 tube in my leslie speaker with one of the 12ax7e
tubes?

You can try, if you like, although I suspect it won't
sound too good.

I understand this will provide added overdrive.

More likely, the 12AX7 will distort before the 6550's
start clipping. Basically, you're just making the
amplifier more sensitive, you just won't have
to crank up the control as much for the same
volume.

Note: one of the 12AU7's in a two-speed Leslie operates
the tremolo/chorale (slow/fast) relay. The relay won't
work if you sub that 12AU7 with a 12AX7.

Is there any risk of
damage to the Leslie?

None I can think of. If you don't like the way it sounds,
put the 12AU7 back in.

--
Ned Carlson
SW side of Chicago, USA
www.tubezone.net