PARTYBUS TO ZOO - SID
zuulkuul & annizio / #afwd - ZOO 2026

Three voices, one resonant filter, about three and a half minutes of
SID acid. Accented sawtooth riffs and slides, a filtered bass/kick and
off-beat noise hats. Tuned on the 8580.

Our text-based song creator describes notes, rhythms, transpositions
and bar order. An off-machine renderer calculates the filter envelopes,
pitch slides and gate changes, packing them into SID register frames.
Repeated bars reuse the same data.

In the demo, BASIC PRINT sends those frames through the screen editor
into the SID's $D700 mirror: music without a machine-code player.
This standalone .sid carries the same rendered frames, wrapped in a
small 6502 player with CIA timing for normal SID players.

Two subtunes, the same bars in two arrangements, 3:30 each:
  1. Release version: built up for listening, the riff alone first,
     pairs, then a chord a bar for the climax.
  2. Demo version: as the demo's credits play it, the chords moving
     from the first bars. In the demo, press space at the end for
     the release version, looping.

Also included: a C64 .prg with the credits PETSCII screen and the release
version looping in BASIC, with its beat-synced colours. No fade or sign-off.
Reset to leave it: RUN/STOP would leave PRINT directed into the SID.
