source file: m1389.txt
Date: Sat, 18 Apr 1998 07:13:26 -0500 (CDT)

Subject: RE: delurking (synthesizer tuning capabilities)

From: mr88cet@texas.net (Gary Morrison)

>You're forgetting the 4 pitch table selection limit.

   There are ways around that of course.  Somebody suggested using what
might be called "instantaneous crossfades" between layers with the
mod-wheel.




>Matching octave boundaries for
>scales over 12 notes would make things easier, in my opinion.

   I'll tell you sir, I'm with you on this one.  But I think you'll find
that - mind-bogglingly if you ask me - we're pretty darned near alone.
Among the people who map(ped) tunings linearly, mismatching octave
boundaries in the tuning with octave boundaries on the keyboard, are,
Easley Blackwood, Ivor Darreg, Jonathan Glasier, Harry Partch (on the
Chromelodeon), Brian McLaren, Bill Sethares, and my K2500-playing friend
Bill Meadows.  And speaking of whom...




>(K2500):  nTET and nCET scales can be
>created at the program level by adjusting a few parameters, and are
>unlimited in step size.  Resolution is 1 cent or better if done correctly

   Perhaps you can provide some insight for Bill Meadows here:  He wants to
map 19TET linearly across the keyboard, which means that you have to set
the step size between keys to about 63.1579 cents.  Keymaps are
12-tone-per-octave-based, so you can't use them.  The other available
tuning facility was to state a step size between keys, consistent across
all of the keyboard, but the resolution of the step-size between keys was 2
cents.  Obviously then setting that to 64 would make the octave sharp by
about 16 cents.

   He and one of the techies at Kurzweil concluded initially that the K2500
had no means of doing that, except by assigning a single (I don't know the
Kurzweil terminology, but the Ensoniq-equivalent term would be
"wavesample") to each individual key and setting its root pitch so that it
works out right.  He says that he later heard of something I think he
called a "function" that conceptually should make it possible.

   Obviously though a general, arbitrary pitch table would be a lot easier.
Do you know of an easier way to do that?





>It's FM timbres make a good counterpoint to today's
>wavetable synthesis.  The Yamaha TX802 has been out of production for quite
>some time

   Does it by chance allow resonant filters to manipulate FM-generated sounds?