Eurorack Reference / modules /joranalogue/contour-1 audit site v0.1 — milestone 3
joranalogue/contour-1

Contour 1

Joranalogue Audio Design

Analogue voltage controlled bidirectional slew limiter and function generator. Can be used as a slew limiter, envelope generator, envelope follower, VC(LF)O, and more. Features separate rise/fall slope control and bending with CV, gate/trigger inputs, loop mode for oscillation, and impedance-compensated outputs.397

Capabilities 5

Envelope Followerenvelope-follower
Fast rise rate tracks signal envelope; fall rate sets decay. Outputs envelope for CV modulation of other modules.397
Envelope Generatorenvelope-generator
Creates AR envelopes via gate input and AD envelopes via trigger input or push button. Output swings 0 to +10 V regardless of gate amplitude.397
LFOlfo
397
Slew Limiter / Portamentoslew-limiter
Bidirectional slew limiter with separate rise and fall rates, slope bending, and CV modulation for both rate and shape.397
Voltage-Controlled Oscillatorvco
In loop/audio-range mode, operates as a temperature-stable VC(LF)O with variable waveshape and 1 V/oct tracking over several octaves.397

Jacks 12 — 8 in / 4 out

NameSignalVoltageDescription
Inputs (8)
Analogue InmixedInput for the signal to be slew limited. In gate/trigger/loop modes, sets the minimum (floor) voltage for each cycle; default is 0 V.397
Fall Bend CV Incv-5V to 5VCV input to modulate the falling slope bend (shape). Receives normalled signal from Rise Bend CV In when unpatched. With bend knob centred, CV range is −5 V to +5 V.397
Fall CV IncvCV input to modulate the falling slew rate. Higher voltage increases slew rate (decreases slew time). Receives normalled signal from Rise CV In when Fall CV In is unpatched.397
Gate IngateIn slew mode: high gate switches source to precision +10 V reference for AR envelopes. In loop mode: gates oscillation on/off. Logic thresholds: +2 V low, +3 V high (Schmitt).397
Hold Inmixed397
Rise Bend CV Incv-5V to 5VCV input to modulate the rising slope bend (shape). Normalised to Fall Bend CV In. With bend knob centred, CV range is −5 V to +5 V.397
Rise CV IncvCV input to modulate the rising slew rate. Higher voltage increases slew rate (decreases slew time). Normalised to Fall CV In for simultaneous modulation; responds at 1 V/oct when both are patched together.397
Trigger IntriggerRising edge resets output to 0 V and triggers a single-shot AD envelope. Logic thresholds: +2 V low, +3 V high (Schmitt).397
Outputs (4)
Fall Gate Outgate0V to 5VGoes high (+5 V) whenever the slew core is falling; low (0 V) at all other times.397
Inv OutmixedInverted analogue output, impedance-compensated.397
Outmixed0V to 10VMain slew-limited output. Highly accurate and impedance-compensated for pitch-accurate CV. Voltage range 0 to +10 V.397
Rise Gate Outgate0V to 5VGoes high (+5 V) whenever the slew core is rising; low (0 V) at all other times.397

Parameters 8

NameTypeRangeBehavior
Fall BendknobBends the falling slope from concave through linear to convex. Changing bend minimally affects slope time in loop mode due to compensation design. Center position is linear.397
Fall Slew Ratefader0.0005s – 30sSets the falling slew rate. Fast at bottom, slow at top. In full mode, slew time ranges from 500 µs to 30 seconds; in audio mode, 500 µs to 30 ms. LED on lever shows falling status and brightness correlates with positive output voltage.397
Frequency Range SwitchswitchSelects between full range (500 µs to 30 s; for use as slew limiter, VCLFO, envelope generator, envelope follower) and audio range (500 µs to 30 ms; for use as VCO, VCF, waveshaper).397
Rise BendknobBends the rising slope from concave through linear to convex. Changing bend minimally affects slope time in loop mode due to compensation design. Center position is linear.397
Rise Slew Ratefader0.0005s – 30sSets the rising slew rate. Fast at bottom, slow at top. In full mode, slew time ranges from 500 µs to 30 seconds; in audio mode, 500 µs to 30 ms. LED on lever shows rising status and brightness correlates with positive output voltage.397
Slew/Loop SwitchswitchLeft position: standard slew limiter or envelope generator mode. Right position: loop mode — circuit continually re-triggers for sustained oscillation. In loop mode, output voltage rises to +10 V then falls to the analogue input voltage, repeating continuously.397
Trigger ButtonbuttonResets the output voltage to 0 V and starts a single-shot AD envelope: voltage rises to +10 V then falls to the voltage at the analogue input. Can also reset the output voltage without triggering a full envelope when used as a reset.397
V/Oct TrimmerknobCalibrates the module's 1V/oct pitch tracking. Accessible from front panel without removing the module. Each module is individually calibrated during production.397

Firmware history 3 versions

VersionReleasedNotes
Revision ENo functional changes.397
Revision DNo functional changes.397
Revision CInitial release.397

References 2

  1. [397]
    Contour 1 User Manualmanual
    verified 2026-05-15
  2. [398]
    Joranalogue Audio Design Contour 1 product pageproduct_page
    verified 2026-05-15