From las8323@rs175174.ks.boeing.com Mon Sep 10 05:56:06 2001
Subject:Re: V5 - espression pedal?


> If an organ has a REAL expression pedal/circuit, it will try to follow
> these curves as much as possible. The end result is that the midrange
> frequencies are attenuated more than the bass and high-treble frequencies
> when the pedal is pulled back (low volume), so that the ear hears about the
> same timbre at all volume levels.

Well, in a REAL organ, the expression pedal brings in extra ranks of *pipes*
while the swell pedal handles the volume of air ("volume" pedal) to the
pipes. Don't remember all the Italian/Latin names -- but who cares?

The Hammond accomplishes this with a large plate style variable
capcitor similar in mechanics to an old analog radio tuner. This
is a not-too-complex tone control, really -- if not totally documented.
In an effort to duplicate it, why not use a "tone control" pedal? So
I shop around and now I'm trying another hair-brained (hey,
gotta have hair *somewhere* :-) idea. Dunno when I'll be done,
but whole concept, basically, is to take a Morley Volume/Wah pedal
apart and "re-equalize" the wah to tone down the response and more
closely emulate the Hammond expression ped. But by keeping the Vol
section intact, still allow for plain old Vol pedal when the gig
really calls for it (those "heavy" days :-). That way, it also
works on "whatever" clone I choose to hook it to with some trimmer
tweaking.

But don't panic, it won't be done anytime soon -- but it can't be
all that hard.

Larry