[.Luke]

Wow. Just from reading the topic, the SNES audio format finally makes sense; an XM style format with samples. I always wondered why all of my favorite games had very different sounds to them.

As for the interpolation, I can kinda relate there. While playing Super Street Fighter II on SNEmulDS on the DS, it probably doesn't have that interpolation as far as I know, so the sound effects and music are crystal clear, (The music sounds a lot better that way.) but when I played it on ZSNES, (Which I later realized had filtering.) I was wondering what the heck was wrong with the sound. It was fairly muffled and compressed.

[muteKi]

ICEknight, on 31 July 2013 - 10:27 PM, said:

...This makes me wonder how would the Game Boy Advance games sound like with those SNES filters and interpolation applied, specially on top of the clear samples you can hear when extracting the songs to MIDI format.

I like just putting on a cubic interpolation through highly advanced (in_gsf), which has pretty comparable sound quality to the we-don't-need-no-stinkin-interrupts performance via midi+soundfont, and has the advantage of not needing a media player that's not winamp.

[Covarr]

So if SNES audio is sample-based, and GBA audio is sample-based, what excuse did Super Mario World: Super Mario Advance 2 have for sounding so completely awful? I'm fairly certain they didn't use the same samples.

[Shadow Hog]

The GBA doesn't have very good DAC, to my understanding. I forget if that's because it doesn't have a proper sound chip, forcing the CPU to handle audio duty, or if it's a memory issue limiting the size of samples, or if I'm completely off-base with my knowledge.

[Andlabs]

GBA isn't sample based: it's two PCM streams and all the work has to be done in software (though you can also use the original Game Boy audio hardware as well). I can't explain the poor quality choices by devs.

[GerbilSoft]

Andlabs, on 05 August 2013 - 05:02 PM, said:

GBA isn't sample based: it's two PCM streams and all the work has to be done in software (though you can also use the original Game Boy audio hardware as well). I can't explain the poor quality choices by devs.

Worse: It's PWM, not PCM. That's why so many games have horribly scratchy music.

[Flygon]

Doesn't the DS also use PWM? Or have I been wrong all these years?

[TmEE]

GBA CPU is dedicated to sound management in the DS. The scratchiness in GBA games has exactly the same reasons why most MD games have shit PCM - inability to maintain jitter free sample playback.

[Maxd]

JaredAFX, on 30 July 2013 - 02:08 PM, said:

I'm pretty knowledgeable about chiptune music. I make stuff in FamiTracker, so I completely understand the NES/Famicom's 2A03 chip and the Famicom's expansions, like the VRC6. I also understand that the Game Boy basically has four FDS (Famicom Disk System) channels. Last, but not least, I get that the Genesis has a Yamaha FM chip and a Texas Instruments PSG chip, and that the two are controlled by a Z80 (the Master System's CPU, as well as a lot of other devices). What I don't understand is the S-SMP, the Super Nintendo/Famicom's soundchip. I've heard that it doesn't make "chiptunes" in the conventional sense because it only uses samples. Is this true? Is there no internal sound that it can make, other than bending the pitch of samples? I'm just confused on the whole subject and I can't find a reliable source; everything conflicts with each other.

EDIT: Changed the topic title to better reflect the conversations going on.

The Gameboy can be made to sound like the FDS or 2A03, but it is an entirely different beast. The two are extremely different, considering the Gameboy has only three (technically 4) pulse width options, a FM-like subtractive synth waveform channel which can also do low-fidelity WAV file playback, and a noisechannel that is very different from the one of the NES. Also, the NES saw various expansion chips and enhanced audio options, the Gameboy saw (and to this day, but that may change in the coming year) no audio expansion.

On the topic of the SNES not being "chipmusic," the deal with it is that a) it isn't really capable of synthesizing its own sounds b) it plays back and manipulates exclusively samples. Despite the Amiga computers being very popular with sample-based music, they can (and still are) used to synthesize unique sounds to the hardware. Aside from the playback means, the SNES is currently "useless" chipmusic production hardware because of its history as being sample-only, the CPU architecture being a bit difficult to work with (8 bit processor and 16 bit addressing and registers is not "smart"), and being a mainly sample-based machine, it is easily outclassed by Amigas and other sample-friendly family computers from the 80's.

The real question to ask is: is chipmusic simply music made from specialized sound chips that generate waveforms? Or is it music made from teeny tiny samples on chips, cassettes, and other small-storage medias? Yes. Is SNES in line with the NES, Gameboy and Genesis? No. The SNES bridged an interesting gap along with the N64 and PSX between the end of tracker-or-MIDI generated music and the playback of actual recordings, like highly-capable Amiga music and other sample-oriented computers.

EDIT: I guess it's worth mentioning that I am an undergraduate student studying composition and I am working with a professor on a research project that includes chipmusic under its umbrella topic "computer music." It may be also worth mentioning that I have been making chipmusic actively for 3 years and I have spent 1 year learning assembly language quirks for Gameboy and NES. And I am a fairly active LSDJ user. If you have questions about Nintendo hardware let me know.

This post has been edited by Maxd: 06 August 2013 - 04:22 PM

[TmEE]

Amiga has no synthesis capability, all the synthesized stuff there is done by softsynths and those you can do an any machine capable of running a user program, even on SNES (but it is much harder than on Amiga, but still possible).

[Maxd]

Thanks for stating those points, those were somewhat glossed over in my post. Correct, there is no true hardware-based synthesis with the Amiga family, and yes, soft synths for the SNES could exist but are unlikely to ever be made (due to lack of demand and programming difficulty).

[dsrb]

Maxd, on 06 August 2013 - 04:15 PM, said:

a FM-like subtractive synth waveform channel which can also do low-fidelity WAV file playback

Can you explain what you mean here? Maybe it's technically accurate somehow, but right now, it just looks like a bunch of disparate terms mashed together in a way that makes no sense whatsoever.

Firstly, FM is very different from subtractive, so I'm not sure what equivalence you're trying to paint there. And as far as I knew, the GB's third channel was simply a low-res PCM channel (not WAV, and people need to stop implying the two are equivalent), nothing more, with the fact that it's often used for triangle bass not implying any real subtractive nature.

[Andlabs]

Flygon, on 06 August 2013 - 11:25 AM, said:

Doesn't the DS also use PWM? Or have I been wrong all these years?

DS is a proper sample-based system, with 16 channels and "ADPCM/PCM formats" as well s synthesis derived from the Game Boy channels.

[Chilly Willy]

TmEE, on 06 August 2013 - 10:49 PM, said:

Amiga has no synthesis capability, all the synthesized stuff there is done by softsynths and those you can do an any machine capable of running a user program, even on SNES (but it is much harder than on Amiga, but still possible).

Actually, it does. Channel 0 can modulate either the volume or frequency of channel 1, and channel 2 can modulate either the volume or frequency of channel 3. Now those were meant to allow tremolo or vibrato, but can and have been used for more than that. The primary use turned out to be modulating the volume at the SAME FREQUENCY as channel being modulated - that allows the volume to be changed at the exact same time as the sample, allowing for higher resolution on the sample (14 bits raw, but those other 6 bits are non-linear... if you adjust them, it's between 12 and 13 bits effective). Most music players allow for using the Amiga sound that way. So do some games and emulators.

And for others, there's nothing inherently bad about PWM. The vast majority of DAC are a combination of resistive ladders and PWM as making a ladder for a full 16/18/20-ish bits requires resistors of too high a precision. So you make a smaller ladder and feed that to a PWM circuit to make the full resolution of the DAC.

[TmEE]

I forgot about the modulation part, but its not really capable - you waste a whole channel on something that you can record and use as a sample on 2 or more channels :P.
Best use is what you described though hehe.