Mods that use VAR Source/Control have to be after Mod that defines the VAR

Polyphonic Analog Synthesizer
Post Reply
devnull
Posts: 24
Joined: Sat Dec 19, 2020 1:00 pm

Mods that use VAR Source/Control have to be after Mod that defines the VAR

Post by devnull » Sun Dec 27, 2020 5:46 pm

It appears that MOD lines that have a VAR source or controller need the MOD line that defines the VAR to be before it (i.e. line that defines the VAR has to have a lower number in the MOD table). This is a bit awkward because there is no way to move a MOD line around. It would be better if the algorithms that processed the MOD lines did not require this (e.g. internally order the lines that have VAR destinations to be processed first).

As an example:

Case 1:
EG 1 Sustain = 50%
Mod Matrix:
Exp1 100% / Constant 8% / Function DIODE(S-C) / VAR 10
VAR10 50% / Constant -30% / Function S+C / EG2 Sustain

This case works as expected.
First line nulls the petal to zero and puts the result in VAR10 (i.e. VAR 10 = Max(0, Exp 1 - 8%).
Second line makes VAR10 Bipolar and modulates Sustain up or down (e.g. crescendo or diminuendo).
The result is that Sustain = 50% + (VAR10 - 30%) - which ranges from Sustain = 10% when Exp1 = 0% to Sustain = 90% when Exp1 = 100%.

Case 2:

EG 1 Sustain = 50%
Mod Matrix:
VAR10 50% / Constant -30% / Function S+C / EG2 Sustain
Exp1 100% / Constant 8% / Function DIODE(S-C) / VAR 10

This case does not work as expected.
This case acts as if VAR 10 = 0% no mater where you set the expression pedal.
The result is that Sustain = 0%.

Post Reply