asb2m10 / dexed

DX7 FM multi plaform/multi format plugin
GNU General Public License v3.0
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Adjust feedback for algorithm 32 in Mk I engine #331

Closed showlabor closed 2 years ago

showlabor commented 2 years ago

Pushing the feedback value up to 7 in algorithm 32 results in digital noise, see issue asb2m10#146. That's not how the original DX7 behaves. This patch tries to fix this issue by scaling the feedback value for algorithm 32. It sounds much closer to the (at least my) DX7 Mk I and doesn't produce the digital noise any more.

In direct comparison, at feedback value 7 it sounds a bit brighter than my original DX7. I tried different scalings (e.g. feedback_shift+3) which sounded a bit too muffled. So overall (feedback_shift+2) sounds closest to my DX7.

This might need further investigaion but for now I think that this scaling is much better than the digital noise currently produced.