LOFI64
Endless lo-fi — on the three SID voices of a real breadbin C64.
Listen
$1964. The first four bars are chords only, then the drums and the melody come in. On a real 6581 the filter sounds a little different — see below.Press RUN and it plays, and it does not stop. No recorded track, no loop, no samples: every note comes from one 16-bit seed. The same seed always plays the same music; N picks a new one:
- Three voices, five jobs: voice 1 is the bass and the drums — kick and snare cut into the bass the way old C64 tunes did it. Voices 2 and 3 are the chords; voice 3 takes the melody when its turn comes.
- Shell voicings, the jazz pianist’s trick: the root in the bass and only the 3rd and the 7th above it. Two notes are enough to say “Dmaj7”, and each new chord moves them the shortest way.
- 75 BPM with a 60/40 swing. A loop of four chords plays four times, then it changes: one chord is swapped, a new loop is written, or the key moves up a fourth.
- A melody that cannot clash: it only uses notes of the chord under it; it states a two-bar motif, repeats it as the chords change, and answers itself at the end of the section.
- A mixer: bass, drums, chords, melody. On/off, level and a filter send per channel — all from the keyboard, while it plays.
What it needs
| Machine | PAL Commodore 64. The music clock is the PAL frame; on NTSC it plays 20% fast and sharp, and is not supported. |
|---|---|
| Sound | SID 6581. The warmth of lo-fi is a low-pass filter, and the 6581’s filter differs from chip to chip — so the cutoff and the resonance are on the keyboard. It plays on an 8580 too; tune the filter from scratch. |
| Controls | Keyboard only. |
| Size | One file, under 5 KB. |
| Version | v1.0 |
Download
The .d64 is a disk image: copy it to an SD card device, or mount it in an emulator. The .prg loads directly. Either way it is LOAD"…",8,1 then RUN. The zip has both, plus the release notes and screenshots.
If you cannot hear the filter, your chip is different. On the breadbin it was voiced on, the cutoff did nothing from $00 to $40 and everything happened between $40 and $50. Walk it with + and -: when the chords suddenly open up, you have found the step. Resonance is R.