Ripsaw

Acid Rain Technology 6HP
OSCILLATOR VCO

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Four-voice supersaw oscillator on the HEX platform · 7 saw-to-square morphing oscillators per voice (28 total, 56 with stereo spread) · Shape, Spread, Shift CV over hard-sync-style detune · stereo L/R with voice detection on insertion.

Patch Ideas · 7

★ Classic supersaw trance lead
Sequencer p> V/O 1 · Shape CCW for saw · Spread 2 o'clock · Shift 0 · Out L/R → stereo delay → reverb · one voice already delivers 7 detuned saws wide in stereo · move Spread by LFO for shimmer
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 4 connections. Modules: Ripsaw, Sequencer, LFO, FX Stereo. Signals: 2 audio, 1 cv, 1 pitch.RipsawSequencerLFOFX StereoShape: CCW (saw)Spread: 2 o'clockShift: 0V/O 11v/octSpread CVcvOut LaudioOut RaudioPitch1v/octOutcvIn LaudioIn Raudioaudiocvpitch
★ Four-voice paraphonic chord
Poly quantizer or chord module → V/O 1-4 · insertion activates all four voices = 28 oscillators (56 stereo) · root held by encoder · single trigger gates a stereo pad through an external envelope/VCA · big cinematic stacks from 6HP
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 7 connections. Modules: Ripsaw, Chord Module, Envelope, Stereo VCA. Signals: 2 audio, 1 cv, 4 pitch.RipsawChord ModuleEnvelopeStereo VCASpread: midShape: 11 o'clockShift: 0V/O 11v/octV/O 21v/octV/O 31v/octV/O 41v/octOut LaudioOut RaudioOut 11v/octOut 21v/octOut 31v/octOut 41v/octOutcvIn LaudioIn RaudioCVcvaudiocvpitch
Supersync sweep lead
V/O 1 from melody sequencer · slow envelope → Shift CV for rising sync-formant sweep each note · Spread moderate · Shape towards square for more harmonics before sync · hard-sync whine multiplied across 28 oscillators
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 5 connections. Modules: Ripsaw, Sequencer, Envelope, Clock, Output. Signals: 2 audio, 1 cv, 1 pitch, 1 trigger.RipsawSequencerEnvelopeClockOutputShape: 2 o'clock (more square)Spread: noonShift: 0 (CV-driven)V/O 11v/octShift CVcvOut LaudioOut RaudioPitch1v/octTrigtrigOutcvOuttrigLaudioRaudioaudiocvpitchtrigger
Audio-rate PWM-style Shape FM
Second VCO square at audio rate → Shape CV · Shape CV responsive to ~500Hz so it behaves like PWM across every one of the 28 saws · adds brightness and sideband content to the swarm without a wavefolder · Spread sets width
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 4 connections. Modules: Ripsaw, VCO Mod, Sequencer, Output. Signals: 2 audio, 1 cv, 1 pitch.RipsawVCO ModSequencerOutputShape: noonSpread: 2 o'clockV/O 11v/octShape CVcvOut LaudioOut RaudioOutcvPitch1v/octLaudioRaudioaudiocvpitch
★ Unison bass through a filter
Spread fully CCW = near unison · Shape 11 o'clock · sub-bass melody on V/O 1 only (other voices off) · Out L → mono low-pass filter → VCA · fat seven-oscillator unison bass with micro-detune chorus — not a thin single saw
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 4 connections. Modules: Ripsaw, Sequencer, Filter, VCA, Envelope. Signals: 2 audio, 1 cv, 1 pitch.RipsawSequencerFilterVCAEnvelopeShape: 11 o'clockSpread: fully CCWShift: 0V/O 11v/octOut LaudioPitch1v/octInaudioOutaudioInaudioCVcvOutcvaudiocvpitch
Stereo drone with modulated Spread and Shift
Hold a long chord on V/O 1-2 · slow LFO → Spread CV (wide/narrow breathing) · slow random → Shift CV (wandering sync formant) · Out L/R into stereo reverb · evolving drone where internal motion replaces LFOs on filter cutoff
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 6 connections. Modules: Ripsaw, Chord, LFO, Random, Reverb. Signals: 2 audio, 2 cv, 2 pitch.RipsawChordLFORandomReverbShape: noonSpread: CV-drivenShift: CV-drivenV/O 11v/octV/O 21v/octSpread CVcvShift CVcvOut LaudioOut RaudioOut 11v/octOut 21v/octOutcvOutcvIn LaudioIn Raudioaudiocvpitch
Percussive pluck with Shift envelope
Short AD envelope → Shift CV for 'pew' formant transient · second short envelope → VCA · Shape CW for square-ish bite · each note gets a hard-sync chirp before settling into swarm · stereo pluck in 6HP
▸ Show diagram
Patch diagramPatch diagram with 6 modules and 7 connections. Modules: Ripsaw, Clock, Envelope Shift, Envelope Amp, VCA Stereo, Sequencer. Signals: 2 audio, 2 cv, 1 pitch, 2 trigger.RipsawClockEnvelope ShiftEnvelope AmpVCA StereoSequencerShape: 3 o'clockSpread: 1 o'clockV/O 11v/octShift CVcvOut LaudioOut RaudioOuttrigTrigtrigOutcvTrigtrigOutcvIn LaudioIn RaudioCVcvPitch1v/octaudiocvpitchtrigger

Behaviors

JP-8000 style supersaw swarm default patch with Shape CCW, Spread at taste

Seven detuned saws per voice using the same offset curves as Roland's JP-8000 supersaw produce the iconic trance-lead swarm. Spread controls width from unison to chorus-heavy without reducing level.

Voice detection by cable insertion patching V/O 2, 3 or 4

Ripsaw adds voices only when their V/O jacks receive cables. One voice = 7 oscillators; four voices = 28 oscillators, doubled across stereo for 56. Paraphony scales with patching.

Shape as saw-square morph Shape knob or Shape CV

Blends every oscillator continuously from sawtooth to square. Mid positions sit in unusual asymmetric territory. Shape CV is audio-rate capable for PWM-style motion across the whole swarm.

Supersync formant sweep Shift knob raised above zero or Shift CV modulated

Raises the pitch of a per-oscillator hard-sync master by a ratio while the slaves keep the original pitch. Classic hard-sync formant whine, but multiplied across 28 oscillators — hence 'supersync'.

Semitone-quantized fine tune menu option · short-press encoder for cents

Fine-tune ring can be locked to semitones for chord-tuned paraphonic voices or left free for cents-level detune offsets. Root pitch stays set via encoder; V/O inputs transpose from there.

Stereo oscillator spread patching Out L and Out R

Each voice's 7 oscillators alternate L / R so a single voice already images wide. Summing to mono cancels some of the wow and fatness — keep stereo downstream to preserve the supersaw character.

HEX firmware platform USB firmware update

Ripsaw is the first firmware for Acid Rain's 6HP HEX platform. Additional free firmware images reflash the same hardware into different modules (granular, delay, etc.), so the panel engraving names the current firmware rather than fixed function.

Controls

Global root pitch Encoder Turn to step all four voices in semitones; short press to access cents fine-tune (0–99); long press to reset to C2.
turn: ±semitones · short press: cents 0-99 · long press: reset to C2 (65.41Hz)
All voices Shape Morphs every oscillator's waveform from saw to square through continuous blend. Applies equally across all 28 oscillators.
CCW: saw · CW: square · continuous morph
All voices Spread Detunes the 7 oscillators per voice using classic 1990s supersaw offset curves. Controls the swarm width from unison to fully detuned chorus.
CCW: unison · CW: wide swarm · curves modelled on JP-8000
All voices Shift Raises the pitch of 28 per-voice hard-sync oscillators, producing supersync formant sweeps.
CCW: no sync · CW: rising sync · responds at audio rate via Shift CV
Global root pitch Fine tune (encoder short-press) Cents fine-tune with optional semitone quantization from the menu.
0-99 cents · quantized or free
Display LED screen Displays encoder value, current musical note and menu state.
shows note letter + octave

I/O

IN · 7

  • V/O 1 -5V to +7V CV
    1V/oct pitch CV for voice 1. Voice 1 is always active. Range tracks C0 to C7.
  • V/O 2 -5V to +7V CV
    1V/oct pitch CV for voice 2. Inserting a cable activates voice 2 (voice detection) and adds 7 more oscillators to the stereo field.
    NORM → voice 2 muted when unpatched
  • V/O 3 -5V to +7V CV
    1V/oct pitch CV for voice 3. Cable insertion activates the voice.
    NORM → voice 3 muted when unpatched
  • V/O 4 -5V to +7V CV
    1V/oct pitch CV for voice 4. Cable insertion activates the voice — full four-voice paraphony at 56 oscillators across L/R.
    NORM → voice 4 muted when unpatched
  • Shape CV -5V to +5V CV
    Modulates Shape parameter. Responsive up to roughly 500Hz so audio-rate PWM-style sweeps are possible.
  • Spread CV -5V to +5V CV
    Modulates Spread. Swarm opens and closes under CV. Audio-rate safe up to ~500Hz.
  • Shift CV -5V to +5V CV
    Modulates Shift, giving CV control over the hard-sync offset for sync-sweep formant motion.

OUT · 2

  • Out L 4–12V peak-to-peak · internal soft clipping
    Left channel. Each voice's 7 oscillators are spread across L and R so the swarm fills the stereo field rather than stacking mono.
  • Out R 4–12V peak-to-peak · internal soft clipping
    Right channel. Complement of Out L; patch both for a wide stereo image or either alone for a mono sum of the swarm.