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+--- Thread: Audio distortion at different speed (/showthread.php?tid=4774)
Audio distortion at different speed - abstractoakbow - 05-30-2018
I noticed that playing using mGBA at different speeds (audio/visual --> target FPS) distorts the audio pitch. I suppose this isn't exactly a "glitch" but is certainly not a welcome feature.
If I had to speculate, I suspect a 60hz tone played at 120 fps (double speed) means now 2 60hz waves fit in one second, or in other words 120hz fits in a second, effectively raising the entire game audio an octave.
Do other GBA emulators face this problem while playing on turbo?
If the devs ever see this, a couple work arounds to consider include:
1) Fixed turbo (fixed at 4x) comes with fixed audio (lower pitch by 4 octaves). [Of course, this assumes emulation is held steady at 4x, and doesn't fluctuate significantly. It would be up to the user to decide if their machine can hold a fixed turbo or not]
2) Variable turbo (such as unbound) comes with variable audio fix (dynamically approximating and lowering audio) to match approximated pitch. This option would of course take more resources to dynamically access the speed at which each frame comes out.
Thoughts or suggestions? Am I the only one finding chipmunk sequels at 6+ octaves too high annoying?
RE: Audio distortion at different speed - endrift - 06-03-2018
I'm probably going to add an option for muting when running at higher speeds but normalizing the pitch when fast forwarding will require DSP stuff that I don't intend to add at the moment.