hellsine = the sine that went to hell. the "hell" is what hard saturation does to a pure sine — and that distorted sine is the gabber kick. so "all-sine + hardcore" is not a contradiction. it is hardcore's literal DNA. the Rotterdam kick is a pitch-enveloped sine clipped past its own skin.

the research question this lane exists to test:

can a complete hardcore track — carrying a full John Williams melodic structure — be built from nothing but Math.sin, and still work as epic study music (continuous, immersive, no dead air)?

bottom-up + compositional, the strictest possible reading of the pop/ posture: one waveform, a whole genre, a whole compositional tradition.

the all-sine law #

a voice is legal iff its sample value is a sum of sin() terms (plus envelopes and memoryless waveshaping of those sines). allowed:

additive sine partials (brass / strings / pad / bell)
sine-on-sine FM (the metallic stab, the hoover scream)
pitch-enveloped sine (the kick body, the riser)
memoryless saturation of a sine — tanh, hard clip, foldback — the harmonics are derived from the sine, so it stays legal. this is the kick. this is the "hell".
ring-mod = product of two sines → still sines.

illegal, no exceptions: white/pink noise, sampled hats/breaks, saw or square oscillators, any audio file decoded as a source. percussion that is "usually noise" (hats, claps) is re-derived here as very high, very short sine blips — honoring the law literally is the point.

the voices (all sine) #

voice	how it's a sine
kick	sine, pitch env ~250→45 Hz over ~35 ms, then `tanh(drive·x)` hard-clipped — the gabber/Rotterdam kick. `drive` is the hell knob.
sub	low sine at the root, sidechain-ducked under each kick (the pump).
brass/strings	additive sine partials (1·2·3·4·5, odd-harmonic bite for brass), vibrato, octave doublings — carries the leitmotif.
hoover	a few detuned sines + rising sine-on-sine FM index + saturation — the aggressive lead, all sine.
stab	2-op sine FM (sine modulates sine, high index), clipped — the hardcore stab.
perc	8–12 kHz ultra-short sine blips (sub-ms decay) = the tick/hat; ring-modded sine pair = metallic open hat.
scream/riser	sine swept up a bar with rising FM index + saturation — the build.

form — John Williams × hardcore × epic study #

tempo 182 BPM, 4/4 (hardcore range)
key D minor (Williams' heroic register), with a step-up key lift at the final restatement
theme a hand-written, singable heroic leitmotif: a leap up, an expressive stepwise descent (Williams hallmark). a contrasting, lyrical B theme is the calm "study" core.

arc (continuous — no dead air, loop-friendly tail; the "study" use-case lives on uninterrupted immersion under a film arc):

overture   theme hinted in soft sine strings, no kick
statement  theme in full sine "brass" + the gabber kick enters
bridge     B theme, kick thins to a pulse — the study zone
develop    theme fragmented + sequenced through related keys, hoover
climax     full gabber kick + theme restated, transposed up (key lift)
coda       theme dissolves back to strings, continuous fade

length ~1:45 (radio edit, slightly long for the epic-study form)

source → track #

pop/hellsine/bin/hellsine.mjs   the all-sine engine (deterministic seed)
  → <out>/hellsine-MASTER.wav   engine → scratch-mix post-FX → Spotify finalize
  → <out>/hellsine.mp3          320k

deterministic: same seed + same flags = byte-identical audio. the theme/harmony are hand-shaped data, not random — "highly melodic" is composed, not stumbled into.

pipeline #

node pop/hellsine/bin/bake.mjs            # render → post-fx → master
node pop/hellsine/bin/bake.mjs <outDir> -- --hell 14 --bpm 182   # tune

reuses pop/dance/bin/scratch-mix.mjs (genre-agnostic beat-locked post-FX, anchored to this engine's own struct.json grid) and a bake.mjs-shaped finalize chain (loudnorm I=-14 / TP=-1.5 / limiter / end fade), same as the dance lane.

mastering note (inherited, see pop/RELEASES.md): pure-sine mixes render dark. hardcore saturation adds upper harmonics so hellsine starts brighter than the trance bed, but A/B every master against a brightened take before release.

tracks #

hellsine — the concept track itself. status: in flight (see pop/RELEASES.md).

maintained by @jeffrey