novelizer — the novel-voice research lane #

Last updated: 2026-07-02

A research lane inside pop/ (sibling of voice/ and dsp/, not a track lane). Its whole job: research and synthesize novel sounds — instrument voices that don't already exist in the AC stable — and prove them on real melodies so the track lanes (and eventually notepat / gm_synth / AC Native) can pick them up.

"Novel" is measured against what AC already plays: sine bells, supersaw, hoover, skrill FM, zitar (Karplus-Strong + jawari), the nullnoise carved-noise engine, the gm_synth waveguide families. A novelizer voice earns its keep by sounding like none of those.

Posture #

Bottom-up + compositional, same as all of pop/. Every voice is a self-contained portable C99 program (libm only) in the AC house style — normalized phase 0..1 advanced by freq / SR per tick, deterministic, no deps — so a keeper can later be ported into fedac/native/src/audio.c, gm_synth.c, or wasm without translation.

Each voice is grounded in a real synthesis-research technique with a citation (Roads, Essl, Verplank/Mathews, Kaegi, Ishizaka–Flanagan, …). The lane is a reading list that compiles.

Layout #

novelizer/
  c/
    novelizer.h        # the harness: WAV writer, test melodies, nv_main()
    voices/<name>.c    # one file per voice, self-contained + harness
    build/             # binaries (gitignored)
  bin/
    analyze.mjs        # WAV → spectral features JSON (FFT, centroid, flux, flatness…)
  out/                 # rendered WAVs + spectrograms + analysis (gitignored)
  REPORT.md            # per-batch findings: novelty / musicality verdicts

The harness contract #

A voice implements one function and hands it to the harness:

#include "../novelizer.h"

static void render(const NvMelody *m, float *out, int nframes) {
  /* full-melody render: voice owns all state, writes mono floats */
}

int main(int argc, char **argv) { return nv_main(argc, argv, "myvoice", render); }

nv_main renders every test melody (or --melody <name>) into out/<voice>-<melody>.wav, peak-normalized to −1 dBFS so voices compare fairly. Melodies exercise different musical demands:

Workflow (per batch) #

1. Pick candidate techniques (novel vs the AC stable).
2. One builder agent per voice: research → write voices/<name>.c → compile (cc -O2 -std=c99 -o build/<name> voices/<name>.c -lm) → render → bin/analyze.mjs + ffmpeg spectrogram → iterate.
3. One judge agent per voice: adversarial novelty / musicality / entertainability scoring from the renders + features + spectrograms.
4. Human listen (@jeffrey, via slab-afplay) → verdicts land in REPORT.md.
5. Keepers graduate: a track lane adopts the voice, or it ports to dance/synths/-style JS, gm_synth, or AC Native.

Analysis #

bin/analyze.mjs <file.wav> prints JSON: duration, peak/RMS/crest, zero-cross rate, spectral centroid (mean/σ), rolloff, flux, flatness, and an f0-vs-harmonics inharmonicity estimate. Spectrograms via ffmpeg -i in.wav -lavfi showspectrumpic=s=1024x512:legend=1 out.png.

Novelty is argued, not computed — the features + spectrogram + A/B against the existing stable are the evidence; the judge (and jeffrey's ears) make the call.