Question on snes sound

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Question on snes sound
by on (#149016)
If for whatever reason, I was to do a port from nes to snes, will the snes output the same sound as you would hear in, say, Super Mario Bros.? Or will it sound different due to the snes sound chip?
Re: Question on snes sound
by on (#149021)
If you try for an exact port, it will sound a bit different, even if you use trivial samples (square, triangle, and noise). The NES APU generates mostly squarish waves at 894.9 kHz through a set of five primitive DACs (digital to analog converters) and relies on analog post-filtering in the console and TV to remove high harmonics. The Super NES S-DSP generates Gaussian-interpolated waves at 32 kHz through a pair of DACs with higher bit depth. Because of the lower sample rate, it has to filter out the high frequencies before sending them to the DAC; hence the use of Gaussian interpolation. But the Gaussian formula saps a lot of the treble, giving the S-DSP a "dark" or "muffled" sound unless you take care to preemphasize your samples properly.

But in practice, it sounds how you want it to sound. Super Mario World and Super Mario All-Stars use a completely rewritten engine with rearranged music, and "Here We Go" from Super Mario Bros. sounds like this and this through it. Later games would re-remix it: Super Mario 64, Super Smash Bros. Melee, Dance Dance Revolution Mario Mix, and Tetris DS.
Re: Question on snes sound
by on (#149024)
Thank your for that in depth answer! :-)
Re: Question on snes sound
by on (#149038)
Caravan Shooting Collection has probably the best example I can name of how to get good-sounding NES audio on the SNES.