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fvdhoef / vera-module

Versatile Embedded Retro Adapter
MIT License
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Increase audio mixing resolution and implement a way to reset waveform phases #27

Closed akumanatt closed 1 year ago

akumanatt commented 2 years ago

This utilizes a full 24-bit DAC range and makes PSG and PCM to have less noise in very low volume ranges while increasing a relatively small about of logic. Also the phase reset allows manually syncing waveform phases per channel which can be done by setting both left/right output to 0 (mute) for at least one sample. A volume value of 0 alone will not reset a phase.

If the mixing change isn't desirable and only phase reset change is wanted then you can just change this one line.

fvdhoef commented 2 years ago

Has this been verified on real hardware?

jburks commented 1 year ago

The increased DAC range has been verified to be at least a neutral change. A-B testing of a VERA PSG "chiptune" resulted in no perceivable difference by volunteer "golden ears." It is believed that this will yield perceivable differences at low volumes, but confirmation of that is still pending.

I don't believe that the phase synchronization change has been tested.