Psych-Tone Sequencer

Pseudo-random sequencer for CV and gate

This module is based on the sequencer part of the "Psych-Tone" synthesizer as published in the "Popular Electronics" magazine from February 1971.

It uses 6 JK flip-flops that basically form a shift register to create a 63 note pseudo-random sequence. The jacks in the left-most column let you tap onto the flip-flops outputs (normal and inverted) for further usage. The LEDs visualize the state of each output.

The behavior of the shift register - and hence the order of the sequence - can be controlled with the scale and direction switches above and below the Tune Select column respectively. The shift register can be triggered by the internal clock ranging from 0.1 Hz to 20 Hz or by an external source via the clock input jack.

The outputs of the flip-flops can be selected to generate a gate signal. Each switch in the Pause Select column selects a flip-flop output to use for the gate signal, where the gate will open if any selected flip-flop output is high.

In the Tune Select column you can select the flip-flop outputs that will contribute to the CV value at the output jack. Each knob selects one of the 12 flip-flop outputs. If the selected output is high, then the corresponding voltage set in the Ratio column will be added to the output value. An offset voltage can also be added to the output value with the knob next to the output jack.

When modulating the Tune Select or Ratio, you can enable S&H for each modulation signal. The S&H is triggered either by the internal clock or (if connected) by the external clock signal.

Features that have been added in this software version compared to the original design:

• clock input jack for external triggering
• output jacks for the flip-flop outputs
• LED indicators
• modulation ability for Tune Select and Ratio
• S&H for modulation
• CV offset on output

If you have any module specific questions, please visit the Monkey Business Audio forum. For questions about Voltage Modular in general, please visit the Cherry Audio forum. If you don't want to ask your question in the forum you can send me a pm or an email.