Pittsburgh Modular Envelope

The Pittsburgh Modular Envelope is a complex multi-stage envelope generator with voltage controllable attack and decay/release. Using the sustain switch to toggle between modes, the Envelope functions as either a 2 stage attack-decay envelope or a 3 stage attack-sustain-release envelope.

The Envelope response for attack and decay/release is continually adjustable between logarithmic, linear, and exponential allowing for precision envelope shaping. Cycle times range from .8ms or 1250Hz at the shortest to at the longest.

This module is incredibly versatile. It can perform as a:

Voltage Controlled Envelope Generator Voltage Controlled Slewing (Portamento) Envelope Follower VCO and Voltage Controlled LFO VC pulse delay VC wave shaper

To Use the Envelope as an Envelope...

Set the Envelope to the default settings. Input a gate signal to the Input jack. Adjust the ATTACK knob to control the attack stage of the envelope. Use the SUSTAIN ON/SUSTAIN OFF Switch to turn sustain on/off. Left for off, right for on. Adjust the DECAY/RELEASE control to adjust the decay/release stages. When sustain is off, the DECAY/RELEASE knob acts as a decay control. When sustain is on, the DECAY/RELEASE knob acts as a release control.

To Use the Envelope as a Voltage Controlled Envelope...

Set the Envelope to the default settings. Input a gate signal to the INPUT jack. Adjust the ATTACK knob to control the attack stage of the envelope. Adjust the SUSTAIN ON/SUSTAIN OFF Switch to turn sustain on/off. Left for off, right for on. Adjust the DECAY/RELEASE control to adjust the decay/release stages.

The top row of jacks (RISE CV, BOTH CV, FALL CV) are CV inputs that control the Attack stage, BOTH the Attack and Decay/Release stage, and Decay/Release stage respectively. The ATTACK NON-LINEARITY/CV IN knob and the DECAY NON-LINEARITY/CV IN knob are attenuverters that positively (turn the knob to the right of 12 0'clock) or negatively (turn the knob to the left of 12 o'clock) control the amount of CV applied to the Attack (RISE) or Decay/Release (FALL) stages.

To Adjust the Response Curve of the Rise and Fall Controls Individually...

The ATTACK NON-LINEARITY/CV IN and DECAY/RELEASE NON-LINEARITY/CV IN knobs each serve a dual function. The ATTACK and DECAY/RELEASE control response can be adjusted from logarithmic to linear to exponential, or anything in between. The following example uses the Attack controls but the Decay/Release works in the same way. Switch the Attack LINEAR/NON-LINEAR switch to Non-Linear. This enables the ATTACK NON-LINEARITY/CV IN control to control the response curve of the Attack. Turning the ATTACK NON-LINEARITY/CV IN full counter-clockwise will set the Attack response to logarithmic. Turning the ATTACK NON-LINEARITY/CV IN to 12 o'clock sets the response to linear. Turning the ATTACK NON-LINEARITY/CV IN full right will set the Rise response to exponential.

To Use the Envelope as an LFO or A Voltage Controlled LFO...

Set the Envelope to the default settings. Switch the CYCLE ON/CYCLE OFF switch to on (up). The attack and decay/release stages act as the waveshape and frequency controls. Turning the ATTACK and DECAY/RELEASE knobs to the left creates a very high frequency triangle wave. Adjusting the the ATTACK and/or DECAY/RELEASE knobs to the right lower the frequency and modify the wave shape. The ATTACK knob controls the left side of the wave shape. The DECAY/RELEASE adjusts the right side of the waveform. Switching a LINEAR/NON-LINEAR switch to non-linear allows the corresponding NON-LINEARITY/CV IN knob to further shape the waveforms.

The top row of jacks (RISE CV, BOTH CV, FALL CV) are CV inputs that control the Attack stage, BOTH the Attack and Decay/Release stage, and Decay/Release stage respectively. The ATTACK NON-LINEARITY/CV IN knob and the DECAY NON-LINEARITY/CV IN knob are attenuverters that positively (turn the knob to the right of 12 0'clock) or negatively (turn the knob to the left of 12 o'clock) control the amount of CV applied to the Attack (RISE) or Decay/Release (FALL) stages. Using the BOTH CV input jack allows the Envelope module to function as a voltage controlled LFO.

Envelope Controls:

LINEAR ATTACK / NON-LINEAR ATTACK SWITCH - Determines the response type of the attack portion of the envelope. Set to linear, the response is always linear. Set to non-linear, the response is assigned using the attack NON-LINEARITY/CV IN attenuator. Full left offers a logarithmic response, setting the knob to 12 o'clock provides a linear response, and turning the knob full right results in an exponential response.

ATTACK CONTROL KNOB - Adjusts the attack time of the envelope.

ATTACK NON-LINEARITY/CV IN ATTENUVERTER - Multifunction attenuverter used to attenuvert incoming attack CV. Turning the knob left of 12 o'clock results in attenuated inverted CV. At 12 o'clock, the CV response is off. Turning the knob to the right of 12 o'clock results in attenuated CV.

SUSTAIN ON/OFF SWITCH - Changes the envelope response. Set to off (left), the envelopes functions as an attack-decay envelope generator. Set to on (right), the envelope functions as an attack-sustain-release envelope generator.

LINEAR DECAY/RELEASE / NON-LINEAR DECAY/RELEASE SWITCH - Determines the response type of the decay/release portion of the envelope. Set to linear, the response is always linear. Set to non-linear, the response is assigned using the decay/release NON-LINEARITY/CV IN attenuator. Full left offers a logarithmic response, setting the knob to 12 o'clock provides a linear response, and turning the knob full right results in an exponential response.

DECAY/RELEASE CONTROL KNOB - Adjusts the decay/release time of the envelope.

DECAY/RELEASE NON-LINEARITY/CV IN ATTENUVERTER - Multifunction attenuverter used to attenuvert incoming decay/release CV. Turning the knob left of 12 o'clock results in attenuated inverted CV. At 12 o'clock, the CV response is off. Turning the knob to the right of 12 o'clock results in attenuated CV.

CYCLE ON/OFF SWITCH - Set to on (up), the envelope will retrigger the attack stage at the end of the decay/release stage causing the Envelope module to cycle.

ENVELOPE PATCH POINTS:

• RISE CV IN - Attack CV input.
* BOTH CV IN - Attack and decay/release CV input.
• FALL CV IN - Decay/release CV input.
* SIGNAL INPUT - Main signal input.
• END OF ATTACK OUT - Gate signal output. Signal goes high at end of attack stage.
• TRIGGER OUT - Trigger output. Trigger created at end of decay/release stage.
• SIGNAL OUT - Main signal output.

Size: 8hp
Module depth with ribbon cable attached: 36.5mm
Power Usage: 35mA