Family 8 — "make it sound like a game." The SNES has a whole second processor for sound — the SPC700, with its own 64 KB of RAM, its own S-DSP, and its own instruction set, talking to the main CPU through just 4 I/O bytes. This family has two on-ramps — tracker music, and driving the DSP straight from C — then the DSP's party tricks.

The ladder

Tracker music (SNESMOD) — compose in a tracker, smconv converts the .it, the lib plays it:

Rung	Example	Developer question
8.1	snesmod_music	How do I play tracker music with transport controls?
8.2	snesmod_music_large	How do I play a >32 KB multi-bank soundbank?
8.3	snesmod_sfx	How do I mix SFX over music?

Raw APU from C (audio v2) — the lib uploads its own resident SPC700 driver; everything else is plain C:

Rung	Example	Developer question
8.4	soundboard	How do I drive the whole audio-v2 engine from C?
8.5	apu_switch	How do I hot-swap APU programs at runtime?
8.6	play_noise	How do I make drums from the S-DSP noise generator?
8.7	pitch_mod	How do I do hardware vibrato (pitch modulation)?
8.8	speech_synth	How do I play BRR speech?
8.9	echo	How do I add echo / reverb from the S-DSP?

The idea in one screen

Sound is a co-processor problem: you never touch the DSP registers from the 65816 directly — you hand a driver a command over the 4 I/O ports and it runs on the SPC700. SNESMOD's driver plays a compiled tracker module; the audio-v2 driver exposes voices, ADSR, BRR samples and the echo unit as C calls (audioLoadSample, audioPlaySampleEx, audioSetEcho…). Both share the same 64 KB of ARAM, so samples, the echo ring and the driver all compete for it.

(Audio examples have no screenshot — the lesson is audible. Run them with sound.)

apu_switch — hot-swapping APU programs at runtime Echo / reverb pitch_mod — hardware vibrato via pitch modulation play_noise — a drum kit with zero samples SFX from WAV SNESMOD Music Example SNESMOD Large Soundbank Music SNESMOD Sound Effects soundboard — the audio v2 engine, driven entirely from C speech_synth — the SNES says "OPEN SNES"