VC ADSR Clock Generator

100% handmade Voltage Controlled ADHSR Clock Generator with discrete transistor core circuit

The Radical Frequencies Voltage Controlled ADSR Generator, is a classic four stage Attack/Decay/Sustain/Release envelope generator, with the option of adding a fifth stage, by utilising the Hold CV input.
The ATTACK, DECAY and RELEASE CV inputs are bi-polar and when a jack is plugged in at the input, the CV is added to the knob position.
The HOLD CV input is uni-polar, so negative control voltages are not taken into account for that particular CV input.
The envelope has a LOOP switch that transforms the module into a CV controlled LFO, that outputs a trigger at the PULSE output, at the end of every cycle, thus making the Radical Frequencies VC ADSR Generator, an analog, voltage controlled CLOCK GENERATOR!.
GATE MODE (LOOP switch - down).
By sending a trigger at the GATE input the VC ADSR is a snappy envelope with bi-polar CV control of the ATTACK, DECAY and RELEASE parameters.
Since these CV inputs are bi-polar, the VC ADSR Generator will respond to negative CV, which is added to the knob position of the ATTACK, DECAY and RELEASE times, thus making them, faster.
HOLD CV input (GATE mode)
When there is a CV present at the HOLD CV input, there is an extra hold stage applied to the output of the envelope, that is proportionate to the CV going into the HOLD CV input, as well as the value of the SUSTAIN parameter. When the SUSTAIN parameter is full CCW, HOLD CV has no effect.
LOOP MODE (LOOP switch - up).
Turning the LOOP switch up, puts the VC ADSR Generator into loop mode.
Frequency can go from approx 5 seconds (but can go much lower with CV applied to the ATTACK and RELEASE CV inputs) , up to audio rate (approx. 580hz), making the VC ADSR Generator a versatile CV source for frequency modulation, as well as ring modulation.
HOLD CV input (LOOP mode)
When no jack is plugged in the HOLD CV input, the frequency of the LFO is determined by the respective ATTACK and DECAY knobs.
When there is a jack plugged into the HOLD CV input, the module becomes a more involved CV generator and the different parameters start to influence each other in a more organic way.
When SUSTAIN is full CW, HOLD time is proportionate to the amplitude of the CV that is present at the HOLD CV input.
The higher the amplitude into the HOLD CV input, the longer the HOLD time.
When SUSTAIN is full CCW, the Hold CV input becomes a crude, end of cycle crossfader, between the DECAY and RELEASE parameters.
High HOLD CV moves the end of cycle towards the value set by the DECAY parameter.
Low HOLD CV moves the end of cycle towards the value set by the RELEASE parameter.

More room for exploration is available when playing with the, in between SUSTAIN values and different HOLD CV values.

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