@enlavin/pi-computer-noises1.1.0

pi-computer-noises

Retro mainframe ambience for pi: a 60Hz mainframe hum with data blips while the agent thinks (70s/80s sci-fi console — WOPR, Star Trek). Fades to silence when the last turn ends.

How it sounds / works

• All sound is synthesized in pure TypeScript. Blips are a near-uniform telemetry stream of short electronic beeps at tightly-clustered pitches (392-523Hz) with a strong octave on top, so the stream's energy sits in 400-1600Hz. The hum bed is a 60Hz mains stack plus the low-mid partials (46/69/139/262/294/370Hz) and two filtered-noise beds that give it a dense 20-400Hz body. Sparse ambient server-room beeps play over the hum even between turns. The hum bed can be switched off on its own (hum off): blips keep playing, the idle drone (and its ambient beeps) goes quiet.
• The spectral balance is tuned for a dense 70s/80s console texture: per-octave weight sits in 400-1600Hz, the hum carries a 20-400Hz body, and there is little of consequence above ~2.6kHz. 13dB crest factor.
• Everything is mixed into ONE continuous PCM stream fed to a single long-lived raw player (pacat / pw-cat / ffplay / play) on a dedicated worker thread, so timing stays sample-accurate and never stutters when the host's event loop is busy.
• One shared instance per user: any number of pi agents elect a single audio owner (Unix socket + O_EXCL lock file) and refcount active turns — hum + blips play while ANY agent is working and stop when the LAST one finishes.

Audio themes

The default is space (the sound above) 🚀. robot 🤖 restores the original original sound: 1170-1290Hz telemetry beeps (fundamental + 3rd + 5th) over a bare 60/120/180Hz mains drone.

Switch at runtime with the /computer-noises command:

/computer-noises                     # interactive menu (sound + hum + theme)
/computer-noises sound on|off        # mute or unmute everything
/computer-noises sound              # toggle
/computer-noises hum on|off         # silence just the idle drone
/computer-noises hum                # toggle the idle drone
/computer-noises theme robot        # switch theme directly
/computer-noises theme              # theme picker
/computer-noises status             # what is active right now

hum off only removes the idle bed (the hum tone stack plus its sparse ambient server-room beeps): data blips still stream while the agent works, and the idle between turns is silent. sound off mutes everything, hum included.

theme default and theme space are the same theme. The old names still work as aliases: reference → space, classic/legacy/old → robot. The status bar shows the active theme as an emoji (🚀 space, 🤖 robot, 🔇 off, plus · hum off while only the hum is switched off); the command line takes plain names. Settings persist to <agent-dir>/computer-noises.json (~/.pi/agent/computer-noises.json by default) and are shared by every pi instance: sound off silences the shared hum and all instances' blips, hum off removes the shared idle drone while leaving blips on, and a theme switch applies to the elected audio owner for everyone (the player is respawned, so a brief gap is expected).

Environment still works and seeds the startup theme. CN_AUDIO_THEME, when set, wins over the persisted one for that process, but the elected audio owner renders for all instances, so a per-shell override only applies reliably when that shell owns the audio:

CN_AUDIO_THEME=robot pi        # old sound
CN_AUDIO_THEME=space pi        # default

An unknown CN_AUDIO_THEME logs a warning and falls back to space. Direct runs take --theme space|robot instead:

bun src/mainframe.ts --audition 8 --theme robot

Install on pi

pi install git:github.com/enlavin/pi-computer-noises
# or local checkout:
pi install /path/to/pi-computer-noises

Enable/disable with pi config. Remove with pi remove /path/to/pi-computer-noises.

Requirements

• A raw-PCM player: pipewire (pw-cat), pulseaudio-utils (pacat), ffmpeg (ffplay), or sox (play).
• On Debian/Ubuntu WSL: sudo apt install pulseaudio-utils.
• OS support: WSL and native Linux. macOS/Windows-native only if ffmpeg or sox is installed. No raw player found → silently no-ops.

Tuning

Edit src/mainframe.ts:

• Both themes live in the THEMES table: per theme scale (blip pitches), blipAmp, partialAmps / partialCutoff (blip harmonic ladder), ambientScale, humPartials (hum tone stack), toneGain, bodyCutoff / bodyPoles / bodyLevel (low noise bed), chatterLevel (mid noise bed), humLevel (hum loudness).
• Shared timing: GAP_BASE / GAP_JITTER (blip spacing), WINDOW_MS (how long blips linger after the last update).

Spectral regression harness (raw s16le mono at 44.1kHz on stdout):

bun src/mainframe.ts --render 12 > /tmp/on.raw              # hum + blips
bun src/mainframe.ts --render 12 --no-blips > /tmp/hum.raw  # hum only

Sample audio clip

Audition standalone: bun src/mainframe.ts --audition 8