StarLab

Strymon 28HP
REVERB DELAY EFFECTS OSCILLATOR FILTER

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Stereo time-warped reverberator with three structures, variable-rate reverb core, regenerative shimmer, glimmer, pre-delay/Karplus-Strong string voice, LFO, resonant low-pass and four-slot favorite presets.

Patch Ideas · 12

★ Diffuse ambient bloom
TEXTURE: diffuse · DECAY 3 o'clock · SHIMMER ~noon with REGEN on · GLIMMER ~10 o'clock, HIGH BAND on · LOW DAMP ~9 o'clock, HIGH DAMP ~1 o'clock · sparse synth plucks bloom into slow octave-stacking wash with soft highs
▸ Show diagram
Patch diagramPatch diagram with 3 modules and 3 connections. Modules: StarLab, Synth, Output. Signals: 3 audio.StarLabSynthOutputTexture: diffuseDecay: 3 o'clockShimmer: noon · REGEN onGlimmer: ~10 o'clock · HIGH BAND onLEFT INaudioLEFT OUTaudioRIGHT OUTaudioOutaudioLaudioRaudioaudio
★ Karplus string voice
enter Karplus (hold ECHO ON + DELAY/TUNE CW until TAP/TRIG red) · FEEDBACK ~2 o'clock · ECHO ON engaged · sequencer 1V/oct into SIZE/PITCH CV · gate into TAP/TRIG CV for plucks · IN GATE for bowed passages · light reverb tail with TEXTURE: dense, DECAY ~11 o'clock
▸ Show diagram
Patch diagramPatch diagram with 3 modules and 4 connections. Modules: StarLab, Sequencer, Output. Signals: 2 audio, 1 pitch, 1 trigger.StarLabSequencerOutputMode: Karplus-StrongFeedback: ~2 o'clockTexture: denseDecay: ~11 o'clockEcho On: engagedSIZE/PITCH1v/octTAP/TRIGtrigLEFT OUTaudioRIGHT OUTaudioPitch1v/octGatetrigLaudioRaudio11. pluckaudiopitchtrigger
Clock-locked dotted-8th delay + plate
ECHO ON engaged · DELAY/TUNE at 3/4 ratio · FEEDBACK ~50% · TEXTURE: dense · DECAY noon · master clock at quarter notes into TAP/TRIG CV · rhythmic delay tails land dotted-8ths, plate reverb glues everything
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 4 connections. Modules: StarLab, Clock, Source, Output. Signals: 3 audio, 1 clock.StarLabClockSourceOutputTexture: denseEcho On: engagedDelay/Tune: 3/4 ratioFeedback: ~50%TAP/TRIGclkLEFT INaudioLEFT OUTaudioRIGHT OUTaudioOutclkOutaudioLaudioRaudioaudioclock
Scale-quantized pitch-shifted tails
hold INFINITE until LED blinks amber · turn SIZE/PITCH while holding INFINITE to pick a scale (e.g. minor blues) · TEXTURE: sparse · REGEN on · SHIMMER ~noon · 1V/oct sequencer into SIZE/PITCH CV — reverb core pitch-tracks the sequencer inside the selected scale
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 3 connections. Modules: StarLab, Sequencer, Source, Output. Signals: 2 audio, 1 pitch.StarLabSequencerSourceOutputTexture: sparseShimmer: noon · REGEN onPitch Quantize: Minor BluesLEFT INaudioSIZE/PITCH1v/octLEFT OUTaudioPitch1v/octOutaudioLaudioaudiopitch
Envelope-ducked reverb
SHAPE: env · DEPTH ~10 o'clock (negative env) · LFO TARGET: filter · LOW PASS engaged, HIGH DAMP ~2 o'clock, resonance low · reverb tails duck under transients then open up on the decay — pumping ambient
▸ Show diagram
Patch diagramPatch diagram with 3 modules and 3 connections. Modules: StarLab, Source, Output. Signals: 3 audio.StarLabSourceOutputShape: envDepth: ~10 o'clock (negative)LFO Target: filterLow Pass: onHigh Damp: ~2 o'clockLEFT INaudioLEFT OUTaudioRIGHT OUTaudioOutaudioLaudioRaudioaudio
★ Infinite frozen pad under new input
play a chord, press INFINITE or gate INFINITE CV · frozen bed holds while new input continues to pass through the reverb structure · TEXTURE: diffuse, DECAY max · play a melody over the pad · CLEAR CV rising edge erases the frozen bed
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 5 connections. Modules: StarLab, Gate, Trigger, Source, Output. Signals: 3 audio, 1 gate, 1 trigger.StarLabGateTriggerSourceOutputTexture: diffuseDecay: maxLEFT INaudioINFINITEgateCLEARtrigLEFT OUTaudioRIGHT OUTaudioOutgateOuttrigOutaudioLaudioRaudio11. erase padaudiogatetrigger
Chorus / flange via modulated pre-delay
ECHO ON bypassed (delay becomes pre-delay) · DELAY/TUNE very short (~9 o'clock) · LFO TARGET: delay · SHAPE: triangle · SPEED ~2 Hz · DEPTH ~11 o'clock · FEEDBACK low for chorus, high for flange · dry signal modulated into reverb
▸ Show diagram
Patch diagramPatch diagram with 3 modules and 3 connections. Modules: StarLab, Source, Output. Signals: 3 audio.StarLabSourceOutputEcho On: offDelay/Tune: ~9 o'clockLFO Target: delayShape: triangleSpeed: ~2 HzLEFT INaudioLEFT OUTaudioRIGHT OUTaudioOutaudioLaudioRaudioaudio
LFO-clocked pitch wobble
master clock into LFO CLK IN · SHAPE: random · SPEED set to /4 clock division · LFO TARGET: pitch · DEPTH ~1 o'clock · reverb core pitch jumps to a random interval every four bars, phase-locked to the rest of the rack
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 3 connections. Modules: StarLab, Clock, Source, Output. Signals: 2 audio, 1 clock.StarLabClockSourceOutputShape: randomSpeed: /4 clock divisionLFO Target: pitchDepth: ~1 o'clockLFO CLK INclkLEFT INaudioLEFT OUTaudioOutclkOutaudioLaudioaudioclock
Two-voice Karplus with external envelope
Karplus mode · IN GATE CV from a gate source continuously bows · EXT LFO IN from a function generator · LFO TARGET: delay (modulates string tuning) · DEPTH centered for subtle vibrato · gentle TEXTURE: sparse reverb behind · playable bowed-string voice with vibrato
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 5 connections. Modules: StarLab, Sequencer, Function, Output. Signals: 2 audio, 1 cv, 1 pitch, 1 gate.StarLabSequencerFunctionOutputMode: Karplus-StrongLFO Target: delayTexture: sparseSIZE/PITCH1v/octIN GATEgateEXT LFO INcvLEFT OUTaudioRIGHT OUTaudioPitch1v/octGategateOutcvLaudioRaudio121. bow2. vibratoaudiocvpitchgate
Self-oscillating resonant LPF voice
LOW PASS on · hold LOW PASS + HIGH DAMP CW for max Q (self-oscillation) · TEXTURE: dense, DECAY low, WET max · sequencer 1V/oct into HIGH DAMP CV (positive V opens filter) to play the resonant sine · reverb tail adds space to the filter pitch
▸ Show diagram
Patch diagramPatch diagram with 3 modules and 3 connections. Modules: StarLab, Sequencer, Output. Signals: 2 audio, 1 cv.StarLabSequencerOutputLow Pass: on · high QTexture: denseDecay: lowWet: maxHIGH DAMPcvLEFT OUTaudioRIGHT OUTaudioPitchcvLaudioRaudioaudiocv
Preset morph spillover
save a dense plate to Favorite slot 1 (hold FAVORITE until green, press slot button) · enable DIP-1 spillover · set manual panel to a diffuse shimmer wash · clock gate into FAVORITE CV · every gate-edge morphs between plate and shimmer with tail crossfade
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 4 connections. Modules: StarLab, Clock, Source, Output. Signals: 3 audio, 1 trigger.StarLabClockSourceOutputFavorite 1: dense plateManual: diffuse shimmerDIP-1: ON (spillover)LEFT INaudioFAVORITEtrigLEFT OUTaudioRIGHT OUTaudioOuttrigOutaudioLaudioRaudio11. morphaudiotrigger
Quantized shimmer interval sweep
SHIMMER ~1 o'clock, REGEN on · INTERVAL CV fed from a stepped random/quantizer (±5V, ±1 oct, semitone quantized) · TEXTURE: diffuse, DECAY ~2 o'clock · tails rebuild at a new pitch interval each step — harmonised ambient
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 4 connections. Modules: StarLab, Random, Source, Output. Signals: 3 audio, 1 cv.StarLabRandomSourceOutputShimmer: ~1 o'clock · REGEN onTexture: diffuseDecay: ~2 o'clockLEFT INaudioINTERVALcvLEFT OUTaudioRIGHT OUTaudioOutcvOutaudioLaudioRaudioaudiocv

Behaviors

Three reverb structures TEXTURE switch

sparse produces audibly distinct reflections — granular-style textures on staccato input, clean tails on sustained. dense is a plate-like tank with fast response that ventures into ambient at long DECAY. diffuse is a slow-building atmospheric wash with reverse-like attacks. Each re-routes the internal tank topology, not a tonal filter change.

Variable-rate reverb core SIZE/PITCH knob or ±2V 1V/oct CV

Scales the process rate of the reverb tank. CCW halves core size and drops regenerating audio one octave; CW doubles size and raises pitch one octave. Combined with SHIMMER it produces pitch-shifted tails that track incoming V/oct.

Karplus-Strong string voice Hold ECHO ON + turn DELAY/TUNE CW until TAP/TRIG LED glows red

Swaps the delay line into a monophonic plucked/bowed string synthesizer. FEEDBACK sets string decay, LOW/HIGH DAMP damps body harmonics, DELAY/TUNE coarse-tunes over 4 octaves, SIZE/PITCH CV is 1V/oct, TAP/TRIG plucks (quick press) or bows (hold). IN GATE CV continuously bows. Exit by holding ECHO ON + turning DELAY/TUNE CCW until TAP/TRIG blinks green.

Karplus pitch-tracking trim Hold LOW PASS + turn INPUT GAIN

Trims V/oct tracking of the Karplus string to compensate for external CV calibration offsets. Noon = nominal; below noon tracks flatter, above noon tracks sharper. Persists through power cycles.

Pitch-quantize scale mode Hold INFINITE until LED blinks amber

Quantizes SIZE/PITCH knob and 1V/oct CV to one of 15 scales shown by a binary pattern on SHIMMER/GLIMMER/FEEDBACK/DELAY LEDs: octave, root+5th, pentatonic, minor blues, Major, Dorian, Phrygian, Lydian, Mixolydian, Aeolian, harmonic minor, whole-tone, minor/Major chord stacks with monotone input, chromatic. Turn SIZE/PITCH while holding INFINITE to pick a scale; hold LOW PASS + turn SIZE/PITCH to set scale portamento.

Delay as clock-locked effect TAP/TRIG CV connected

DELAY/TUNE becomes a clock divider/multiplier with eleven ratios (1/4, 1/3, 1/2, 2/3, 3/4, 1/1, 3/2, 5/3, 7/4, 2/1, 5/2) around the knob. Delay time maxes at 7.5 s with a 3 s clock period × 5/2. ECHO ON routes the delay into the wet bus; bypassed, DELAY/TUNE is a simple pre-delay into the reverb.

Infinite hold with continuous play INFINITE button or gate on INFINITE CV

Freezes the signal present at the reverb input; new incoming audio continues to be processed by the reverb structure over the frozen bed. Latching by default; hold REGEN at power-up to switch to momentary. Differs from IN GATE which mutes the input entirely.

Regenerative vs. input shimmer REGEN button

Regenerative (LED green): shimmer sits inside the reverb feedback loop, producing the classic octave-stacking ambient bloom. Input (LED off): shimmer applies pitch-shift once at the input of the reverb structure — flat pitched wash without compounding octave stacks. Interval set by SHIMMER knob secondary function (hold REGEN + turn).

Resonant low-pass at output LOW PASS button engaged

Repurposes HIGH DAMP as a 24 dB/oct variable-resonance low-pass at the final output. HIGH DAMP CV still controls cutoff (positive V opens). Hold LOW PASS + turn HIGH DAMP knob to set resonance (Q) — CW peaks, CCW gentler roll-off. Disable LOW PASS to restore HIGH DAMP's reverb-core damping role.

LFO envelope follower SHAPE = env

Replaces the LFO with an envelope follower driven by input dynamics. SPEED sets envelope decay rate; DEPTH is centered at noon — CW for positive depth, CCW for negative. Target via LFO TARGET. Combined with filter target, creates dynamic reverb ducking.

External modulation via EXT LFO IN Cable patched into EXT LFO IN

Any external CV is routed through the LFO TARGET switch. DEPTH knob becomes a bipolar attenuverter with unity at the CW/CCW extremes and zero at noon. Lets function generators or envelopes drive SIZE/PITCH, delay time or filter cutoff without using the dedicated CV inputs.

LFO clock sync with ratios Cable in LFO CLK IN

Syncs LFO with phase alignment to the incoming clock. SPEED knob turns into a discrete clock div/mult: /8 /6 /5 /4 /3 /2 on the first half, ×2 ×3 ×4 ×5 ×6 ×8 on the second half, 1:1 at noon. Works for any SHAPE, including env.

Favorite preset spillover DIP switch 1 ON (rear)

Enables reverb tail spillover when toggling between the manual panel state and the selected Favorite preset via FAVORITE CV or button. Off: preset recall cuts the tail. Four preset slots are recalled by holding FAVORITE + pressing one of the four center buttons (SHIMMER/GLIMMER/FEEDBACK/DELAY).

CV response at power-up Hold REGEN / HIGH BAND / ECHO ON at power-up

INFINITE CV toggles latching↔momentary by holding REGEN at power-up (default latching). IN GATE CV toggles with HIGH BAND hold (default momentary). ECHO ON CV toggles with ECHO ON hold (default latching). Persists until changed.

Controls

Global DRY Unprocessed signal level to output. Analog path, zero-latency, never digitized.
min: mute · noon: unity · max: +3dB boost
Global INPUT GAIN Gain into reverb core through soft-clipping input stage.
LED: green = clean · red = soft-clip · blue = input gated by IN GATE CV
Global WET Overall wet signal level to output.
WET CV: ±5V offset sums with knob
Reverb DECAY Reverb tail length. At high values decay time is shaped by the FILTER section.
DECAY CV: ±5V offset
Reverb SIZE / PITCH Variable processing rate of the reverb core. Scales core size and pitches regenerating audio.
±1 oct range · min: 1/2x size · max: 2x size · CV: 1V/oct ±2V
Reverb TEXTURE Three reverb structures select the grain of the tail.
sparse: granular-sounding distinct reflections · dense: plate-like fast response · diffuse: slow-building atmospheric wash
Reverb INFINITE Button. Holds reverb input indefinitely; new audio keeps being processed by the reverb. 2s hold enters PITCH QUANTIZE scale mode.
Default latching · momentary via REGEN-hold at power-up
Global FAVORITE Button recalls currently selected preset. Hold + center-button selects 1 of 4 slots. Hold until green flashes to save.
4 preset slots · DIP-1 ON enables spillover between preset and manual
Harmonics SHIMMER Pitch-shifted reverb voicing amount. OFF at fully CCW.
Interval ±1 oct · secondary: hold REGEN + turn for interval · −detune/+detune near noon · CV: ±5V
Harmonics GLIMMER Dynamic harmonic spectrum enhancement applied to input or regenerating signal.
OFF at CCW · CV: ±5V
Harmonics REGEN Button. Toggles shimmer placement: regenerative (inside reverb loop) vs. input (before reverb structure).
LED green: regenerative · LED off: input shimmer
Harmonics HIGH BAND Button. Selects which harmonic band the glimmer enhances.
LED green: high-band · LED off: low-band
Delay / Karplus FEEDBACK Regeneration in the delay line. In Karplus mode, sets string decay and structure resonance.
CV: ±5V offset
Delay / Karplus DELAY / TUNE Pre-delay 0–1.5s (log taper). With TAP/TRIG CV becomes clock div/mult. In Karplus mode, coarse string tuning over 4 octaves or fine 12 semitones with SIZE/PITCH CV.
Clock ratios: 1/4, 1/3, 1/2, 2/3, 3/4, 1/1, 3/2, 5/3, 7/4, 2/1, 5/2 · max delay 7.5s at 3s clock × 5/2
Delay / Karplus ECHO ON Button. Routes delay output to WET bus (mixed with reverb). Bypassed = pre-delay only. In Karplus mode, mixes the dry string with wet.
Default latching · momentary via ECHO ON-hold at power-up
Delay / Karplus TAP / TRIG Button. Tap tempo in delay mode. Quick press plucks string in Karplus; hold continuously bows.
Clock range 25 ms – 3 s · max delay time 7.5s
Filter LOW DAMP Removes low-end from output and from the regenerating reverb core as knob turns CW. In Karplus mode, damps low end of string.
CW: aggressive low-cut
Filter HIGH DAMP Removes high-end from regenerating reverb structure as knob turns CW. With LOW PASS engaged, becomes 24dB/oct resonant low-pass output filter. In Karplus mode, damps string decay harmonics.
HIGH DAMP CV: ±5V · positive V opens filter
Filter LOW PASS Button. Converts HIGH DAMP into a 24dB/oct variable-resonance low-pass at the output.
Secondary: hold LOW PASS + turn HIGH DAMP to set LOW PASS resonance (Q)
LFO SPEED LFO period. Sets envelope decay when ENV shape selected. Acts as clock div/mult when LFO CLK IN detected.
15 s (0.067 Hz) – 1/15 s (15 Hz) · clock div 8/6/5/4/3/2 first half · mult 2/3/4/5/6/8 second half · noon = 1:1 · CV: ±5V
LFO SHAPE Six LFO waveforms: triangle, square, ramp, saw, random, envelope.
env shape responds to input dynamics; DEPTH sets envelope sensitivity
LFO DEPTH Modulation amount. Attenuverter for EXT LFO IN signal. With ENV shape: noon = off, CW = positive env, CCW = negative env.
OFF at CCW (non-env) · CV: ±5V · attenuverter centered at noon when EXT LFO IN patched
LFO LFO TARGET Three-way switch: delay (delay time / Karplus tuning), pitch (SIZE/PITCH), filter (HIGH DAMP cutoff).
Filter target subtle without LOW PASS engaged

I/O

IN · 20

  • LEFT IN 20 Vpp max · 22 kΩ AUDIO
    Left audio input. Use alone for mono.
  • RIGHT IN 20 Vpp max · 22 kΩ AUDIO
    Right audio input.
  • INFINITE 0–5V rising edge
    Engages infinite hold of input into reverb. Latching by default; momentary via REGEN-hold power-up.
  • IN GATE 0–5V GATE
    Gates audio into reverb (INPUT GAIN LED blue when muted). In Karplus mode, continuously bows string. Momentary by default; latching via HIGH BAND-hold power-up.
  • FAVORITE 0–5V rising edge
    Rising edge toggles between manual panel state and selected Favorite preset.
  • SHIMMER ±5V CV
    Offset for SHIMMER amount; knob sums with CV.
  • INTERVAL ±5V
    Shimmer pitch interval, quantized to semitones over ±1 octave.
  • HIGH DAMP ±5V
    Offset for filter cutoff; positive V opens filter.
  • GLIMMER ±5V
    Offset for GLIMMER amount.
  • LFO CLK IN 0–5V rising edge CLK
    Syncs LFO with phase alignment; SPEED knob becomes clock div/mult.
  • SPEED ±5V
    Offset for LFO SPEED.
  • DEPTH ±5V
    Offset for LFO DEPTH.
  • EXT LFO IN modular level CV
    External modulation source routed to LFO TARGET. DEPTH acts as attenuverter centered at noon.
  • SIZE/PITCH ±2V reverb · 0–4V Karplus · 1V/oct CV
    1V/oct reverb pitch CV summed with knob. In Karplus mode, tracks string pitch over 4 octaves (0–4V).
  • WET ±5V
    Offset for WET level.
  • DECAY ±5V
    Offset for DECAY time.
  • CLEAR 0–5V rising edge AUDIO
    Clears audio data from reverb buffer.
  • FEEDBACK ±5V
    Offset for FEEDBACK / Karplus string decay.
  • ECHO ON ±5V
    Toggles ECHO ON button. Latching by default; momentary via ECHO ON-hold power-up.
  • TAP / TRIG 0–5V rising edge · 25 ms – 3 s clock range GATE
    Clock-sets delay time (DELAY/TUNE acts as divider/multiplier) or plucks the Karplus string on rising edge.

OUT · 2

  • LEFT OUT 20 Vpp max · 1 kΩ AUDIO
    Left audio output. Sums mono if RIGHT OUT unpatched.
  • RIGHT OUT 20 Vpp max · 1 kΩ AUDIO
    Right audio output.