Grayscale Permutation 18hp 12hp 6hp Variant Turing Machine Voltages expander

Permutation: a random sequencer based on the Turing Machine

Permutation uses a digital shift register to generate unpredictable CV and gate patterns that can be locked into repeating loops. The concept is based on the Turing Machine, an open source module designed by Tom Whitwell, which takes inspiration from vintage analog randomization circuits such the Buchla 266 "Source of Uncertainty" module.

These modules retain the core functionality of the Turing Machine while adding new features such as dedicated pulse outputs for each bit of the shift register, CV inputs for all parameters, and an internal bipolar VCA. Locked sequences are also saved across power cycles automatically to facilitate easier recording and live performance.

Variant is an expander module based on the Volts and Voltages expanders for the Turing Machine. Gate voltages from the first 8 steps of Permutation are combined using a mixing console paradigm. Gates are shifted to the next mixer channel with each clock pulse, providing dynamic variations of the mix. Positive and negative mix outputs are provided, each with scaling knobs and CV inputs.


User Manual Version 1.1 covers all features of Permutation and Variant.


Permutation restock in progress. Preorder to reserve a module (ETA: July 2023).


Variant restock in progress. Preorder to reserve a module (ETA: July 2023).

Permutation Comparisons

Each version of Permutation has a slightly different feature set. Note that the 6hp version has an assignable CTRL input. Holding the Clear/Write switches down for a few seconds assigns the CV input to Shift, Bits, or Amp (the internal VCA).

Size 18hp 12hp 6hp
Sequence CV output
Inverted sequence CV output
White noise output
Clock output
Gate outputs 16 8 1
Bipolar VCA Assignable
Pause/Clock switches
Clear/Write switches
Clear/Write CV inputs
+12V current draw 48 mA 48 mA 48 mA
-12V current draw 14 mA 14 mA 14 mA


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