gris
gris is a digital recreation of the famous Throbbing Gristle Gristleizer — a vactrol-based tremolo and voltage-controlled filter. the LFO drives a vactrol envelope follower with asymmetric attack/release, modulating either the VCA amplitude, the filter cutoff, or a blend of both. 10 runtime-selectable waveforms from triangle and ramp to smooth random, stepped random, exponential envelope, and noise. germanium-style diode clipping at the input.
character modes
all six knobs retain identical semantics across all modes — the toggle changes what moves, not what the knobs do.
- classic: original Gristleizer behavior. LFO modulates VCA/VCF at a fixed rate and depth.
- envelope: input signal dynamics modulate LFO depth. playing harder increases tremolo intensity. attack 30ms, release 400ms. depth controls how much the envelope influences modulation.
- drift: random per-cycle modulation offset. each LFO cycle generates a new random value added to the modulation, scaled by depth. at low depth, subtle organic wobble. at high depth, the effect becomes unstable and chaotic.
LFO waveforms
| shape | waveform | description |
|---|---|---|
| 0 | triangle | linear rise and fall |
| 1 | ramp up | linear rising |
| 2 | ramp down | linear falling |
| 3 | square | hard on/off |
| 4 | smooth random | filtered sample-and-hold |
| 5 | stepped random | classic sample-and-hold |
| 6 | exponential envelope | attack/decay envelope (rate-dependent) |
| 7 | noise | per-sample random |
| 8 | sine | pure sine wave |
| 9 | exponential rise | power curve (quadratic) |
mode routing
- VCA: signal multiplied by vactrol envelope
- VCF: signal passes through; filter cutoff modulated
- MIX: blend of VCA and VCF based on bias knob
filter
1-pole lowpass with resonance feedback:
- cutoff: 20hz to 20khz (logarithmic mapping)
- resonance: 0 to 3.0 feedback
- active in VCF and MIX modes only
violence region
when depth × bias pushes modulation past unity, the effect enters a deliberately unstable overdrive: the open phase amplitude wobbles chaotically and the output stage drives ~2.5× harder. the gate floor itself is preserved — the silence stays absolute.
output stage
after the VCA, the signal passes through a warm asymmetric saturator:
- drive scales with level to a max of 3.4x, boosted further in the violence region
- positive half saturates harder than the negative half, adding even harmonics (warmth) without softening the odd-harmonic grind
- when the tremolo gate closes, the output is sample-held at silence — full-depth gating stays absolutely quiet
bypass
while bypassed the wet chain stays warm — the LFO keeps running, so the tempo led keeps ticking and re-engaging is click-free.