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Heliophobe told me about checking to see what frequency the sound rate was. I'm glad he told me because I found something interesting out. True indeed, whether your sound is running at 8000, 11025, 22050, and 44100 will make a big difference in the quality of your sound. But, there is one more thing that too will make a big difference in the quality of your sound. And I'd say 99.9% of emulators (excluding the music players) don't even consider it (Mabye they do but I haven't noticed). The bit rate of the sound. Most emulators only support 8-bit sound (compadability reasons, I guess). 16-bit sound is the bomb! I did a little experiment. I took Nosefart and listened to every combination of sound possible. Here's my results...




11025__8:  Badly Muffled, extremely hissy


22050__8:  A little muffled, extremely hissy


44100__8:  Not muffled, still hissy


48000__8:  Clear from muffle, still hissy





11025_16:  Badly Muffled, still hissy


22050_16:  A little muffled, no hiss


44100_16:  Clear from muffle, no hiss


44800_16:  Clear from muffle, no hiss

What does this have to do with anything (you might ask)? A whole lot when it comes to digital sound emulation. Sound that is in 8-bit isn't the best, but you can really hear the difference between 11025, 22050, and 44100 sound. Charles' emulator, SMS Plus, uses 44100 sound. Meka uses 23105 (I think. It still rounds off to 22050). But anyway, it's not really that SMS Plus is better but that it uses a higher frequency rate. Previously when I kept saying hissy or hiss, I meant background distortion or noise. The SMS has a noise channel. This causes conflicts in the quality of the sound when you use low sound rates. If the sound rate his higher, then there's less distortion. But what I found out, if the bitrate is 16, then there's close to no distortion (Your human ear can't pick it up). So the end result, anything that comes out of it sounds real or like natural noise. Before you harp on me, Yes, I know that you can adjust the frequency rates. But you can't adjust the bit rates that the sound comes out. Mabye this is an option to be considered in the future. Am I right, or wrong?

Chris :o)

CHASMS uses 16-bit, 44khz sound all the time. I don't know if it's just that air (coder of MikMod) completely kicks ass, but no matter how high I turn up the mixing quality, it makes almost no impact on overall cpu usage of the emulator. If intelligently coded, it's entirely possible to do high quality sound mixing without much of a speed hit, so I don't really know why emulators continue to use 8-bit sound (aside from that they may not think it's necessary, but I agree with you, it does make a difference)

The one thing that has sort of irritated me is that the sound quality is ever-so-slightly, but still noticably degraded when I switched to Stereo sound from Mono. I guess that's one of the drawbacks of using a WIP sound-mixing core. I'd might try using Mono mixing for SMS games and only Stereo mixing on GG games, but that means I have to shutdown and re-initialize the sound library each time it loads a game... which would probably produce audible popping. So that'd be bad. But I suppose I should at least try it out.

Or it may be that my Awe64 is a gigantic piece of crap. Idunno.

- vecna

indeed. if you consider the sound to be made up of 4 sources mixed together, you would probably limit each channel to be 1/4 or less of the actual output volume.

so basicly you can say an 8bit psg emulation is like adding 4 6bit sounds together, and thats gotta be bad

cant explain it further, but im sure you understand or will work out your own idea

Author	Message
Consolemu Guest	Sound Issues Posted: Mon May 29, 2000 5:35 am
Consolemu Guest	Heliophobe told me about checking to see what frequency the sound rate was. I'm glad he told me because I found something interesting out. True indeed, whether your sound is running at 8000, 11025, 22050, and 44100 will make a big difference in the quality of your sound. But, there is one more thing that too will make a big difference in the quality of your sound. And I'd say 99.9% of emulators (excluding the music players) don't even consider it (Mabye they do but I haven't noticed). The bit rate of the sound. Most emulators only support 8-bit sound (compadability reasons, I guess). 16-bit sound is the bomb! I did a little experiment. I took Nosefart and listened to every combination of sound possible. Here's my results... `11025__8: Badly Muffled, extremely hissy 22050__8: A little muffled, extremely hissy 44100__8: Not muffled, still hissy 48000__8: Clear from muffle, still hissy 11025_16: Badly Muffled, still hissy 22050_16: A little muffled, no hiss 44100_16: Clear from muffle, no hiss 44800_16: Clear from muffle, no hiss` What does this have to do with anything (you might ask)? A whole lot when it comes to digital sound emulation. Sound that is in 8-bit isn't the best, but you can really hear the difference between 11025, 22050, and 44100 sound. Charles' emulator, SMS Plus, uses 44100 sound. Meka uses 23105 (I think. It still rounds off to 22050). But anyway, it's not really that SMS Plus is better but that it uses a higher frequency rate. Previously when I kept saying hissy or hiss, I meant background distortion or noise. The SMS has a noise channel. This causes conflicts in the quality of the sound when you use low sound rates. If the sound rate his higher, then there's less distortion. But what I found out, if the bitrate is 16, then there's close to no distortion (Your human ear can't pick it up). So the end result, anything that comes out of it sounds real or like natural noise. Before you harp on me, Yes, I know that you can adjust the frequency rates. But you can't adjust the bit rates that the sound comes out. Mabye this is an option to be considered in the future. Am I right, or wrong? Chris :o)

vecna Guest	Posted: Mon May 29, 2000 8:46 pm
vecna Guest	CHASMS uses 16-bit, 44khz sound all the time. I don't know if it's just that air (coder of MikMod) completely kicks ass, but no matter how high I turn up the mixing quality, it makes almost no impact on overall cpu usage of the emulator. If intelligently coded, it's entirely possible to do high quality sound mixing without much of a speed hit, so I don't really know why emulators continue to use 8-bit sound (aside from that they may not think it's necessary, but I agree with you, it does make a difference) The one thing that has sort of irritated me is that the sound quality is ever-so-slightly, but still noticably degraded when I switched to Stereo sound from Mono. I guess that's one of the drawbacks of using a WIP sound-mixing core. I'd might try using Mono mixing for SMS games and only Stereo mixing on GG games, but that means I have to shutdown and re-initialize the sound library each time it loads a game... which would probably produce audible popping. So that'd be bad. But I suppose I should at least try it out. Or it may be that my Awe64 is a gigantic piece of crap. Idunno. - vecna

Limbs a Flyin' Guest	Posted: Tue May 30, 2000 4:05 pm
Limbs a Flyin' Guest	indeed. if you consider the sound to be made up of 4 sources mixed together, you would probably limit each channel to be 1/4 or less of the actual output volume. so basicly you can say an 8bit psg emulation is like adding 4 6bit sounds together, and thats gotta be bad cant explain it further, but im sure you understand or will work out your own idea

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