4ms EnvVCA
Analog envelope, slew limiter, and VCA in one
8 HP Eurorack module
The EnvVCA is a 100% analog envelope generator, slew limiter, and VCA in one module. It produces linear envelopes ranging from audio-rate modulation up to 30-minute sweeps, with an integrated exponential VCA whose gain tracks the envelope output. Its Follow jack enables slew limiting, ASR/ADSR envelope generation, portamento, and exotic audio filtering, making it a deeply versatile utility voice-shaping tool.
Features
- 100% analog linear envelope generator
- Low-noise low-distortion DC-coupled exponential VCA
- Rise and Fall times from 100 microseconds to over 30 minutes via CV
- Sliders and switches only: approximately 1.25ms to over 2 minutes
- Independent Rise and Fall sliders with Slow/Med/Fast range switches
- Time CV jack with independent attenuverter knobs for Rise CV and Fall CV
- Blue/red LEDs on Rise CV and Fall CV indicate modulation strength and polarity
- Cycle button for looping LFO-style envelopes
- Cycle jack for gate-controlled cycling with inverted logic when button is on
- Trigger jack fires one-shot envelopes on rising edges above 2.5V
- EOR (End of Rise) gate output for chaining and sequencing events
- Env Level slider independently controls Env jack output without affecting VCA gain
Controls & Jacks (19)
- Cycle — Toggle cycling/LFO mode. When on, envelopes cycle continuously. Button illuminates orange when cycling.
- Fall CV — Attenuverter controlling how much the Time CV jack affects fall time. Turn right to lengthen with positive CV, left to shorten with positive
- Rise CV — Attenuverter controlling how much the Time CV jack affects rise time. Turn right to lengthen with positive CV, left to shorten with positive
- Time CV — Modulates rise and fall times through Rise CV and Fall CV attenuverters.
- EOR — End of Rise gate output for chaining and sequencing events.
- Cycle — Toggles cycling state with a gate signal.
- Audio Out — VCA output with audio modulated by envelope.
- Env — Envelope output, attenuated by Env. Level slider.
- Follow — Slew limiter input for complex envelope generation and filtering effects.
- Trigger — Fires a one-shot envelope when receiving a trigger of at least 2V.
- Audio In — Audio input to the VCA.
- Rise — Selects rise time range: Fast (2.5Hz to 800Hz), Med (20 sec to 18Hz), or Slow (5 min to 1.5 sec).
- Rise — Controls rise time of envelope. Move up for slower rise, down for faster rise. Range depends on Rise switch position. White LED indicates en
- Rise CV LED — Indicates strength and polarity of Time CV modulation on rise time. Blue = lengthening, Red = shortening.
- Fall — Controls fall time of envelope. Move up for slower fall, down for faster fall. Range depends on Fall switch position. White LED indicates en
- Fall — Selects fall time range: Fast (2.5Hz to 800Hz), Med (20 sec to 18Hz), or Slow (5 min to 1.5 sec).
- Fall CV LED — Indicates strength and polarity of Time CV modulation on fall time. Blue = lengthening, Red = shortening.
- Env.
- Env. Level — Attenuates the envelope output on the Env jack from 0V (bottom) to 10V (top). Does not affect internal VCA envelope. White LED indicates env
How-To Guides
- Basic Cycling Notes with VCA
- Clock-Triggered Notes
- ASR Sustain Envelope from Gate
- ADSR Envelope with Attenuator
- Ratcheting Burst Effect
- Advanced Ratcheting Bursts
- Exponential and Logarithmic Envelope Shapes
- Portamento Glide on CV Sequences
- Slew Limiter Low-Pass Audio Filter
- EOR Gate for Sequential Event Chaining
Explore the interactive EnvVCA panel on BleepDex — tap any control to learn what it does.
