intellijel/swells

Swells

Intellijel

Multi-model stereo reverb with nine reverb models and a built-in SWELL Generator (multi-mode envelope follower), featuring comprehensive per-model controls, LO-FI modifier, FREEZE/REVERSE/BURST momentary FX, and nine CV inputs with attenuverters.972

Capabilities 2

Envelope Followerenvelope-follower
SWELL Generator operates as a multi-mode envelope follower with five modes (Follow, Gated, One Shot, Delayed One Shot, Looped) and outputs 0–5V.972
Stereo Reverbstereo-reverb
Nine selectable reverb models with comprehensive controls including PREDELAY, SIZE, DECAY, HI/LO DAMP, EQ, and per-model EBB/FLOW parameters.972

Jacks 16 (13 in / 3 out)

NameSignalVoltageDescription
Inputs (13)
IN LaudioLeft audio input; normalled to right input when right is unpatched.972
IN RaudioRight audio input; receives left input signal when unpatched (normalled).972
LEVELcv-10V to 10VShared CV input affecting both INPUT and MIX controls via their respective attenuverters.972
Mod Input 1cv-10V to 10V972
Mod Input 2cv-10V to 10V972
Mod Input 3cv-10V to 10V972
Mod Input 4cv-10V to 10V972
Mod Input 5cv-10V to 10V972
Mod Input 6cv-10V to 10V972
Mod Input 7cv-10V to 10V972
Mod Input 8cv-10V to 10V972
SCmixed-10V to 10VSidechain audio or CV input used as trigger source for the SWELL generator.972
TRIGtrigger≥1.2VAssignable trigger input that can be routed to FREEZE, REVERSE, SWELL, or BURST functions.972
Assignable destinations
FREEZETriggers FREEZE — captures a moment in sound for infinite sustain through the selected reverb model.972 REVERSETriggers REVERSE — reverses audio playback from the pre-delay.972 SWELLTriggers SWELL — manually fires the SWELL Generator envelope.972 BURSTTriggers BURST — adds noise or feedback alongside the input to add energy to the signal.972
Outputs (3)
OUT Laudio972
OUT Raudio972
SWELLcv0V to 5VDedicated output for the SWELL envelope generator signal, patchable to other modules.972

Parameters 33

NameTypeRangeBehavior
ALTbuttonButton that accesses ALT functions labelled in grey on the panel. Press to enter the Alt Page (auto-exits after 20s of inactivity); press and hold for momentary access. While the Alt Page is active, parameter LEDs display modulation depth/sign instead of value.972
BURSTbuttonInjects a momentary burst of noise or feedback into the reverb input; hold for momentary activation, can be latched or assigned to TRIG.972
CV Attn 1-8knobAttenuverters for the 8 modulation inputs above each main slider, also normalled to SWELL when nothing is patched. Centre position = no modulation; turn off-centre in either direction to assign SWELL or external CV to that parameter.972
DECAYfaderSets reverb fade time from quick decay to near-infinite sustain; also affected by SIZE and DAMP settings.972
DRIVEbuttonToggles saturation/overdrive on the INPUT signal path to the reverb (does not affect dry signal). Access via ALT + REVERSE button.972
EBBfaderModel-specific parameter whose function changes per reverb model; may be unipolar or bipolar depending on the model.972
Zones
ritual
Shift Down
Shift Up
  • Shift Down -100–0%Pitch-shift down, amount proportional to position below center.972
  • Shift Up 0–100%Pitch-shift up, amount proportional to position above center.972
EF GAINknob0.5x gain – 2.5x gainSets the gain of the trigger source feeding the SWELL envelope follower, independently of the main signal path; accessed via ALT + RISE.972
EQfaderTilt EQ on reverb signal only; upper range boosts highs and cuts lows, lower range boosts lows and cuts highs, center position has no effect.972
FALLknob10ms – 5000msSets SWELL envelope release time with an exponential response; level drops quickly at first then shallows.972
FLOWfaderModel-specific parameter whose function changes per reverb model; may be unipolar or bipolar depending on the model.972
Zones
buckets
Random
Sine
  • Random -100–0%Random modulation, depth proportional to position below center.972
  • Sine 0–100%Sine-wave modulation, depth proportional to position above center.972
fog
Random
Sine
  • Random -100–0%Random modulation, depth proportional to position below center.972
  • Sine 0–100%Sine-wave modulation, depth proportional to position above center.972
blur
Random
Sine
  • Random -100–0%Random modulation, depth proportional to position below center.972
  • Sine 0–100%Sine-wave modulation, depth proportional to position above center.972
shadow
Random
Sine
  • Random -100–0%Random modulation, depth proportional to position below center.972
  • Sine 0–100%Sine-wave modulation, depth proportional to position above center.972
velvet
Random
Sine
  • Random -100–0%Random modulation, depth proportional to position below center.972
  • Sine 0–100%Sine-wave modulation, depth proportional to position above center.972
asterion
Random
Sine
  • Random -100–0%Random modulation, depth proportional to position below center.972
  • Sine 0–100%Sine-wave modulation, depth proportional to position above center.972
FREEZEbuttonFreezes input to the reverb for infinite sustain; tap to toggle, hold for momentary. Can be latched or assigned to TRIG input.972
HI-DAMPfaderReduces high-frequency decay time; slider top applies minimal damping, slider bottom applies maximum damping.972
HPF->VERBknob50Hz – 400HzSets highpass filter cutoff on the signal entering the reverb; accessed via ALT + MIX.972
IN/SC/OUTswitchSelects the audio source that feeds the SWELL envelope follower: IN L/R (pre INPUT), SC sidechain input, or reverb output (pre MIX).972
INPUTknobSets signal level from IN L/R into the reverb path (post TRIM); also controls drive amount when DRIVE is active.972
LEVEL Attn (INPUT)knobAttenuverter controlling the amount of LEVEL CV applied to the INPUT parameter. Shares the single LEVEL CV input with MIX.972
LEVEL Attn (MIX)knobAttenuverter controlling the amount of LEVEL CV applied to the MIX parameter. Shares the single LEVEL CV input with INPUT.972
LO-DAMPfaderReduces low-frequency decay time; slider top applies minimal damping, slider bottom applies maximum damping.972
LO-FIswitchApplies a model-specific audio degradation or modification effect at three levels: OFF, MIN, and MAX.972
LPF->EFknob≥40HzSets lowpass filter cutoff on the SWELL trigger source signal; CCW is 40Hz, CW disables the filter. Accessed via ALT + FALL.972
MIXknobControls the dry/wet balance of the output signal.972
MODEbuttonSelects the trigger mode of the SWELL Generator (ALT + SWELL). Press ALT to enter the Alt Page, then press MODE (the SWELL button) to toggle between the five modes. The MODE button LED colour identifies the active mode (Blue / Amber / Green / Purple / Red). The five modes are enumerated as parameter_assignments.972
Assignable destinations
FollowBlue. Classic envelope follower — the input level determines the output level.972 GatedAmber. When the threshold is reached, the input signal is treated as full scale.972 One ShotGreen. Passing the threshold triggers a full-length envelope.972 Delayed One ShotPurple. Passing the threshold triggers a delayed full-length envelope, fired when the signal drops below the threshold again.972 LoopingRed. Looping envelope — passing the threshold retriggers. (Manual prose also labels this mode 'Looped'.)972
MODEL 1/2/3switchSelects reverb model number 1, 2, or 3 within the chosen bank; combined with MODEL X/Y/Z to select one of nine models.972
MODEL X/Y/ZswitchSelects reverb bank X, Y, or Z; combined with MODEL 1/2/3 switch to choose one of nine models.972
PREDLYfader0ms – 250msSets reverb pre-delay time; also controls reverse time for the REVERSE effect.972
REVERSEbuttonReverses input signal to the reverb. Reverse time (100ms–2s or clock divisions) is set by holding REVERSE and adjusting PREDLY. Can be synced to TRIG clock.972
RISEknob10ms – 5000msSets SWELL envelope attack time with a logarithmic response; initial rise is faster and slows near the end.972
SIZEfaderControls perceived reverb size; each model has its own SIZE range from small to massive.972
SWELL buttonbuttonManually triggers the SWELL envelope. Momentary by default; hold SWELL and press ALT to latch. Can be reassigned to the TRIG input via TRIG Assign.972
THRESHknobSets signal level at which SWELL activates; CCW gives more frequent swells, CW gives fewer.972
TRIG AssignbuttonOpens the TRIG Assignment page via ALT + FREEZE; allows toggling which functions (FREEZE, REVERSE, SWELL, BURST) respond to the TRIG input. Button LEDs show AMBER when assigned.972
TRIMknob0.5x gain – 2.5x gainAdjusts input gain for IN L/R; accessed via ALT + INPUT. Default x1 gain shown by fading LED.972
TYPEbuttonSelects the BURST noise type: White Noise, Pink Noise, Velvet Noise, High Feedback on PREDLY, or Unburst (v1.1). Accessed via ALT + BURST.972

Firmware history 2 versions

VersionReleasedNotes
1.12026-04Added Unburst (TYPE option that smoothly kills reverb buffer signal); Alt Page timeout after 20 seconds of inactivity; TRIG Assignment Page timeout; Glitchy Switch Mode toggle (buffers clear by default when switching models); LED behavior updates for TRIM, HPF->VERB, EF GAIN, and LPF->EF.972
1.02026-04972

References 3

  1. [972]
    Intellijel Swells User Manual v1.1manual
    verified 2026-05-26
  2. [973]
    Intellijel Swells Quick Startmanual
    ⚠ verified 2026-05-26 · manufacturer changed since last verified
  3. [974]
    Intellijel Swells product pageproduct_page
    verified 2026-05-26