[iiwusynth-devel] Velocity-to-filter default modulator

[M. Nentwig]

Hello again,

I examined a soundfont (grandpiano2), that was written with SFEDT 1.20.
Putting a couple of printf-lines into iiwu_defsfont.c revealed this:
It implements a modulator, which fits exactly to the description in
SF2.01 section 8.4.2. Only the amount is 2400 instead of -2400. But
since it's a preset level modulator, the amount has to be added to that
of the default modulator, they cancel each other, no modulation remains.
Gotcha!
My conclusion is, that the default GM modulator has to be 'hacked´ to
fit to the specs in its definition, but produces a vel-to-filter curve
without a jump at V=64.
Now it's time for some listening tests.
Many other sound fonts (Vintage dreams, steinbow_mg.sf2, mk_1_rhodes.sf2
to name a few) don't use modulators at all, so once the default GM
modulators are right, they should produce the same result in Iiwusynth
or a hardware synth. Well, they should...

Cheers

Markus