While testing, I heard a lot of digital sounding noise on the output when turning the volume or pan pots. I first suspected it to be digital noise from the midi connection.
After extensive testing, I've concluded that this is not noise per se, instead it has two causes:
- The midi input is stepped, each pot has max 128 positions
- The CV is linear, so changes are more audible when the volume is low
I tried adding filtering of the output CVs, e.g. making the change take more time even if the midi said to change things instantly. This worked fairly well but when turning the volume pot slowly I could still hear stepping at the lower end.
This is because the steps are of equal size, but audio loudness is exponential. A one unit change when the volume is low is much larger and audible than a one unit change when the volume is high.
I have already added support for response curves, changing to an "exp_1" curve took care of most of the stepping.
As for the filtering, a "max 64 units change per update" gave a good result. 256 is too much.
Right now the filtering happens at the DAC update, it should be moved to the midi side as the rest of the matrix works as it should.
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