Contour 1

Joranalogue 8HP
SLEW ENVELOPE FUNCTION LFO VCO

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Voltage-controlled slew limiter and function generator with independently bendable rise and fall slopes. Generates AR/AD envelopes, LFO, VCO, or envelope follower. Slope times 500µs to 30s.

Patch Ideas · 6

Improved saw oscillator
Loop mode, audio range. Self-patch FALL gate to TRIG. so each cycle resets instantly to 0V for a clean saw edge.
Walkthrough
  1. Flip the Slew/Loop switch to Loop (right).
  2. Flip the Full/Audio switch to Audio (right).
  3. Push the Rise slider near the top (slow rising).
  4. Push the Fall slider all the way to the bottom (fastest fall).
  5. Centre both Bend knobs (linear slopes).
  6. Patch Contour 1 FALL output into its own TRIG. input.
  7. Patch Contour 1 OUT into a VCF input, then the VCF into your mixer.
  8. Move the Rise slider to change pitch; the fall now snaps to 0V instantly.
Signal out OUT — audio-rate sawtooth, 0 to +10V, fundamental set by Rise slider.
Listen for A bright, buzzy sawtooth tone. Without the self-patch the waveform sounds duller; with FALL→TRIG. the reset edge sharpens it noticeably.
▸ Show diagram
Patch diagramPatch diagram with 2 modules and 2 connections. Modules: Contour 1, VCF. Signals: 1 audio, 1 trigger.Contour 1VCFSlew/Loop: LoopFull/Audio: AudioRise: slowFall: fastTRIG.trigFALLtrigOUTaudioInaudio11. self-reset for clean sawaudiotrigger
★ AR envelope from a gate
Slew mode. Feed any gate into GATE; Contour 1 rises to +10V while high, falls back to IN voltage when released.
Walkthrough
  1. Flip the Slew/Loop switch to Slew (left).
  2. Flip the Full/Audio switch to Full (left).
  3. Set the Rise slider low-to-middle (short attack).
  4. Set the Fall slider around the middle (medium release).
  5. Centre both Bend knobs for linear slopes.
  6. Patch a gate from a sequencer or keyboard into the GATE input.
  7. Patch a VCO into a VCA input, and Contour 1 OUT into the VCA CV.
  8. Play notes: the envelope opens the VCA while the gate is high.
Signal out OUT — unipolar 0 to +10V AR envelope synced to the incoming gate.
Listen for Classic attack-release shape under each note. Longer Fall slider gives lingering tails; a concave Fall bend makes the release feel more natural.
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 3 connections. Modules: Contour 1, Sequencer, VCA, VCO. Signals: 1 audio, 1 cv, 1 gate.Contour 1SequencerVCAVCOSlew/Loop: SlewFull/Audio: FullGATEgateOUTcvGategateCVcvInaudioOutaudioaudiocvgate
★ AD envelope with trigger reset
Slew mode. A rising edge on TRIG. resets to 0V and fires a full rise→fall — great for drums and plucks.
Walkthrough
  1. Flip the Slew/Loop switch to Slew (left).
  2. Set Rise slider near the bottom for a fast attack.
  3. Set Fall slider low-to-middle for a short decay.
  4. Turn the Fall Bend knob slightly counter-clockwise (concave) for a natural decay.
  5. Patch a trigger source into TRIG.
  6. Patch Contour 1 OUT into a VCA CV input.
  7. Tap the front-panel Trigger button to preview the envelope without patching.
Signal out OUT — one-shot AD envelope, 0 to +10V, fires on each trigger edge.
Listen for Snappy percussive envelope. Every trigger punches the output up to +10V and back down; Fall slider controls the decay length.
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 3 connections. Modules: Contour 1, Sequencer, VCA, VCO. Signals: 1 audio, 1 cv, 1 trigger.Contour 1SequencerVCAVCOSlew/Loop: SlewTRIG.trigOUTcvTrigtrigCVcvInaudioOutaudioaudiocvtrigger
★ Envelope follower
Slew mode, full range. Fast Rise tracks peaks, moderate Fall sets decay — extract a CV envelope from any audio.
Walkthrough
  1. Flip the Slew/Loop switch to Slew (left).
  2. Flip the Full/Audio switch to Full (left).
  3. Push the Rise slider all the way down (fastest attack).
  4. Set the Fall slider around the middle for a musical decay.
  5. Turn the Fall Bend knob counter-clockwise (concave) for a natural release.
  6. Patch an audio source (drum loop, voice, guitar) into the IN jack.
  7. Patch Contour 1 OUT into a VCF cutoff input as the follower CV.
  8. Raise the Rise slider slightly if sharp transients cause clicks.
Signal out OUT — positive envelope CV tracking the amplitude of the IN signal.
Listen for The filter opens and closes with the dynamics of the source. Fast transients punch through; slower material produces smoother swells.
▸ Show diagram
Patch diagramPatch diagram with 3 modules and 2 connections. Modules: Contour 1, Audio Source, VCF. Signals: 1 audio, 1 cv.Contour 1Audio SourceVCFSlew/Loop: SlewFull/Audio: FullRise: fastestFall: moderateINaudioOUTcvOutaudioCutoffcvaudiocv
Pulse width and delay from a trigger
Slew mode. A trigger produces two gates: RISE is wide during the rise time, FALL fires afterward — the rise time becomes the delay.
Walkthrough
  1. Flip the Slew/Loop switch to Slew (left).
  2. Set the Rise slider to control the gate width you want on RISE.
  3. Set the Fall slider to control the gate width you want on FALL.
  4. Patch a clock or trigger source into TRIG.
  5. Patch RISE (+5V gate) into a VCA gate or drum trigger — this fires immediately.
  6. Patch FALL (+5V gate) into a second trigger destination — this fires after the rise completes.
  7. Adjust the Rise slider to change the delay between the two events.
Signal out RISE — +5V gate during rise stage · FALL — +5V gate during fall, delayed by the rise time.
Listen for Two rhythmic hits per incoming trigger, spaced by the Rise setting. Great for creating flams, echo-like doubles, or timed gate windows.
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 3 connections. Modules: Contour 1, Clock, VCA, Drum. Signals: 2 gate, 1 trigger.Contour 1ClockVCADrumSlew/Loop: SlewTRIG.trigRISEgateFALLgateTrigtrigGategateTriggate121. width gate2. delayed triggergatetrigger
FM/AM VCO with audio IN
Loop mode, audio range. Feed an external oscillator into IN; Contour 1 oscillates on top of it, combining FM and AM.
Walkthrough
  1. Flip the Slew/Loop switch to Loop (right).
  2. Flip the Full/Audio switch to Audio (right).
  3. Set Rise and Fall sliders to roughly equal positions for a symmetric waveform.
  4. Centre both Bend knobs (required for clean 1V/oct tracking).
  5. Patch a 1V/oct pitch CV into Rise Rate CV (it normals to Fall Rate CV for tracking).
  6. Patch a second oscillator's output into the IN jack — start with a low amplitude.
  7. Patch Contour 1 OUT into a mixer or VCF.
  8. Raise the modulator amplitude to deepen the FM/AM effect; try bend CV for extra motion.
Signal out OUT — audio oscillator whose lower bound is modulated by the IN signal, producing combined frequency and amplitude modulation.
Listen for A complex, metallic timbre that morphs as you change the modulator's pitch and level. Small amounts sound like vibrato + tremolo; large amounts get aggressive and FM-like.
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 3 connections. Modules: Contour 1, Modulator VCO, Pitch CV, Mixer. Signals: 2 audio, 1 cv.Contour 1Modulator VCOPitch CVMixerSlew/Loop: LoopFull/Audio: AudioINaudioRise Rate CVcvOUTaudioOutaudio1V/octcvInaudio11. normalled to Fallaudiocv

Behaviors

AR Envelope gate → GATE

High gate triggers rise to +10V; releasing gate triggers fall. Rise and fall times set by sliders.

AD Envelope trigger → TRIG.

Rising edge resets to 0V then rises to +10V and falls. Manual button fires envelopes without patching.

Slew Limiter / Portamento CV → IN

Smooths voltage changes at the IN input. Impedance-compensated output maintains pitch accuracy on 1V/oct sequences.

LFO / VCO loop mode

Continuously re-triggers, producing variable-shape waveform. Rise/fall sliders set frequency and shape. 1V/oct tracking in audio mode.

Controls

slew core Rise Slider Sets rising slew rate. Bottom = fast, top = slow.
Full mode: 500µs–30s · Audio mode: 500µs–30ms
slew core Fall Slider Sets falling slew rate. Bottom = fast, top = slow.
Full mode: 500µs–30s · Audio mode: 500µs–30ms
slew core Rise Bend Knob Shapes rising slope from concave through linear to convex.
CCW: concave · noon: linear · CW: convex
slew core Fall Bend Knob Shapes falling slope from concave through linear to convex.
CCW: concave · noon: linear · CW: convex
mode Slew/Loop Switch Left: slew limiter / envelope. Right: loop mode (LFO/VCO).
Loop: output rises to +10V then falls to IN voltage, repeating
mode Full/Audio Switch Sets frequency range. Full: LFO/envelope/slew. Audio: VCO/VCF range.
Full: 17mHz–1kHz loop · Audio: 17Hz–1kHz loop
manual Trigger Button Manually fires trigger: resets output to 0V then executes rise/fall.
Creates AD envelope in slew mode
calibration V/Oct Trimmer Front-panel trim pot for pitch tracking calibration in VCO mode.
Factory calibrated; adjust only when needed

I/O

IN · 8

  • IN any CV/audio CV
    Analogue signal input for slew limiting. Sets minimum voltage in loop mode (0V default).
  • GATE +2V low / +3V high threshold GATE
    In slew mode: switches source to +10V for AR envelopes. In loop mode: gates oscillation.
  • TRIG. +2V low / +3V high threshold GATE
    Rising edge resets output to 0V and fires single-shot rise/fall (AD envelope).
  • HOLD +2V low / +3V high threshold GATE
    High gate slows the slew core to near-standstill, effectively freezing the output until released.
  • Rise Rate CV 1V/oct (when both equal for pitch tracking) CV
    Voltage control of rise rate. Normalizes to Fall Rate CV.
    NORM → Fall Rate CV
  • Fall Rate CV CV CV
    Voltage control of fall rate.
  • Rise Bend CV ±5V CV
    Modulates rising slope shape. Normalizes to Fall Bend CV.
    NORM → Fall Bend CV
  • Fall Bend CV ±5V CV
    Modulates falling slope shape.

OUT · 4

  • OUT 0–+10V
    Main slew-limited output signal.
  • INV. 0–-10V
    Inverted output signal.
  • RISE 0/+5V gate GATE
    Gate output, high (+5V) while slew core is rising.
  • FALL 0/+5V gate GATE
    Gate output, high (+5V) while slew core is falling.