Filter gain modulation not working correctly

[David Healey]

@dannytaurus going back through the commits now to see where it appeared

[Lindon]

@David-Healey try April last year.....

[David Healey]

@Lindon My thought too. I've tried builds all the way back to 2023 and the issue is still there, so maybe this is a bug that has always been and I just never noticed - although I thought I'd used filters like this in the past without issue...

I'll see about implementing a fix.

[Christoph Hart]

@David-Healey afaik it was always like this it used the gain mode to modulate between zero position and the target value

[David Healey]

@Christoph-Hart

The dB readout for the modulator shows the correct value (I've increased it to 18dB here to make it clear) but that value doesn't make it to the filter. Maybe that's why I thought it used to work because I was seeing the correct number.

[David Healey]

Turned out to be a nice simple one, Claude fixed it.

[Christoph Hart]

@David-Healey yeah but doesn‘t that just break existing projects?

[David Healey]

@Christoph-Hart Might do... or fixes them :D

Preprocessor definition? Or another idea?

[David Healey]

Another little weirdness I noticed with the filter. Once a voice ends the filter value jumps to its previous value, this causes artifacts (clicks/pops) with other voices that are still playing.

[David Healey]

So after more poking around this issue with the filter values for voices overwriting each other also seemed to be present in the harmonic filter. It's very easy to recreate I don't know why it hasn't come up before, I think not many people are using voice start mods with poly filters or something.

I've updated the PR with the additional fix from Claude. In the process I also got it to fix a smoothing issue and a display issue.