Compressor Module — Dynamics Compressor

A shared processor module used by all six synth engines (Neuro, BIA, Kick, Snare, Hihat). Juno uses a dedicated limiter instead.

Exports

Export	Signature	Purpose
paramDefs	{}	9 parameter definitions
build	(ctx, params) → {input, output, nodes}	Creates compressor subgraph: split → dry/wet → SC HPF → compressor → makeup → sum
update	(nodes, params) → undefined	Updates AudioParam values on an existing compressor graph

Params

Param	Range	Default	Description
compThreshold	–60–0 dB	–24	Level above which compression begins
compRatio	1–20	4	Amount of gain reduction above threshold
compAttack	0.001–0.1 s	0.003	How quickly the compressor responds
compRelease	0.01–1 s	0.1	How quickly compression releases
compKnee	0–40 dB	30 (Neuro) / 0 (drums)	Softens the transition at threshold
compMakeup	0–24 dB	0	Output boost to compensate for gain reduction
compMix	0–1	1	Dry/wet blend
compSC	off/on	off	Sidechain HPF on detection circuit
compSCFreq	20–1000 Hz	200	Sidechain HPF cutoff frequency

Signal Flow

input → split → (→ SC HPF →) comp → makeupGain → wetGain → sum → output
              └→ dryGain →────────────────────────────→ sum

When SC HPF is on, the compressor detection hears a highpass-filtered version of the signal, preventing low frequencies from triggering gain reduction.

Integrations

• Neuro: full 9 params, knee default 30 (soft), GR meter via formula
• Kick/Snare/Hihat/BIA: full 9 params, knee default 0 (hard), shared module build() via backward loop

Previously each drum engine had an inline createDynamicsCompressor() with only 4 params (threshold, ratio, attack, release). They now use the shared module's build() for consistent feature coverage.