Chiptune: Encyclopedia II - Chiptune - Technology

Chiptune - Technology

Historically, the "chips" used were sound chips like the analog-digital hybrid Atari POKEY on the Atari 400/800, the MOS Technology SID on the Commodore 64, the Yamaha YM2149 on the Atari ST, AY-3-8910 on MSX and ZX Spectrum, the Yamaha YM3812 on IBM PC compatibles, and the Ricoh 2A03 on the Nintendo Entertainment System or Famicom. For the MSX several sound upgrades, such as the Konami SCC, the Yamaha YM2413 (MSX-MUSIC) and Yamaha Y8950 (MSX-AUDIO, predecessor of the OPL3) and the OPL4-based Moonsound were released as well, each having its own characteristic chiptune sound.

The technique of chiptunes with samples synthesized at runtime continued to be popular even on machines with full sample playback capability; because the description of an instrument takes much less space than a raw sample, these formats created very small files, and because the parameters of synthesis could be varied over the course of a composition, they could contain deeper musical expression than a purely sample-based format. Also, even with purely sample-based formats, such as the MOD format, chip sounds created by looping very small samples still could take up much less space.

These sample-based chiptunes were often used in crack intros, since they had to be squeezed into any spare space available on the disk of the cracked software.

As newer computers stopped using dedicated synthesis chips and began to primarily use sample-based synthesis, more realistic timbres could be recreated, but often at the expense of file size (as with MODs) and potentially without the personality imbued by the limitations of the older sound chips.

The standard MIDI file format, together with the General MIDI instrument set, describes only what notes are played on what instruments. General MIDI is not considered chiptune as a MIDI file contains no information describing the synthesis of the instruments.

Many common file formats used to compose and play chiptunes are the SID, MOD, and several Adlib based file formats.

Adapted from the Wikipedia article "Technology", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki