Dead Man's Catch v0.3-beta for the Mutable Instruments Peaks module

Dead Man's Catch Version 0.3-beta

WARNING: Due to a nasty bug in this release, installation is NOT recommended at this stage unless you have been requested to assist with testing.

This is a beta release of Dead Man's Catch, which is modified firmware for the Mutable Instruments Peaks eurorack synth module, in the same way that Bees-in-the-Trees is modified firmware to the Mutable Instruments Braids eurorack synth module.

This release of Dead Man's Catch adds two things to the standard Peaks firmware:

• it unlocks a hidden feature which Olivier Gillet, the owner of and principal developer at Mutable Instruments, put into the Peaks firmware from the outset: the Bouncing Ball envelope generator. The Bouncing Ball envelope emulates a ball which is thrown into the air and then allowed to fall back to earth and bounce several times - think of a basketball bouncing on a basketball court. The envelope output equates to the height of the ball at any instant.
• it adds dual Turing Machines, which are semi-random looping CV sequencers, modelled closely on the Music Thing Turing Machine.

These instructions assume reasonable familiarity with Peaks. If in doubt, please consult the official Peaks manual.

After installing Dead Man's Catch on your Peaks module (see below for instructions), the Bouncing Ball function is accessible as a fifth alternative mode, and the Turing Machine as a sixth alternative mode. First put your Peaks into alternative function mode by holding the FUNCTION button for one second (it starts blinking). In the factory peaks firmware, there are four alternative functions available:

• Mini step-sequencer (4-step in twin mode, 2-step in split mode)
• Trigger delay/shaper
• Trigger stream randomiser
• Digital drum synth

In Dead Man's Catch v0.3-beta, the Bouncing Ball envelope generator is a fifth alternative mode, immediately after the digital drum synth function. The Bouncing Ball function is indicated by the top two function LEDs (that is, the ENV and the LFO LEDs) flashing.

The Turing Machine is a sixth alternative mode, immediately after the Bouncing Ball envelope generator. The Turing Machine function is indicated by the first and third (from the top) LEDs (that is, the ENV and the TAP LEDs) both flashing. Press the FUNCTION button again to cycle back to the first alternative function (the mini step-sequencer).

Bouncing Ball controls

Controls for the Bouncing Ball envelope generator are as follows.

In TWIN and EXPERT modes, the knobs from top to bottom control:

• Gravity - increasing values reduce the acceleration due to gravity, so that twisting the knob clockwise simulates a bouncing ball on the Moon, or an asteroid, and turning it counter-clockwise simulates a bouncing ball on Kepler-452b.
• Bounce energy loss - how much energy is dissipated as heat each time the ball bounces. Increasing values reduce the energy loss, and at high values, the ball just bounces forever. Think of it as how hard a basketball is pumped up. At low values, the ball is soft and flat, and hardly bounces at all. Higher values equate to a progressively higher air pressure inside the ball, and thus a bouncier ball.
• Initial amplitude - the height from which the ball is thrown upwards - similar to throwing the ball upwards from progressively higher levels of the Eiffel Tower. Turning the control clockwise reduces the initial amplitude.
• Initial velocity - how hard the ball is thrown upwards.

In SPLIT mode, the knobs from top to bottom control:

• Channel 1 initial velocity and gravity
• Channel 1 bounce energy loss
• Channel 2 initial velocity and gravity
• Channel 2 bounce energy loss

Initial amplitude is set to minimum (i.e same as knob fully clockwise) and cannot be adjusted in SPLIT mode.

Turing Machine controls

If you are unfamiliar with the way in which a hardware Music Thing Turing Machine works, it is strongly recommended that you read Tom Whitwell's explanation so that the following explanations make more sense. The Turing Machine implementation in Dead Man's Catch is not an exact recreation of Tom Whitwell's hardware Turing Machine module, but it is inspired by it.

Two independent Turing Machines are available, one on each of Peaks' two channels. Triggers received on the TRIG1 input advances the Turing Machine 1 shift register by one step (subject to the Clock Division ratio, see below), and triggers received on the TRIG2 input advances the Turing Machine 2 shift register. Each Turing Machine outputs a voltage on the OUT1 and OUT2 outputs, respectively. The value of the output voltage is indicated (approximately) by the brightness of the TRIG1 and TRIG2 illuminated push buttons.

In EXPERT mode, you can, of course, use a Turing Machine on just one of the Peaks two channels, and some other function on the other channel.

Controls for the Turing Machines are as follows.

In TWIN and EXPERT modes, the knobs from top to bottom control:

• Probability - sets the probability (p) that a bit in the LSB (least significant bit) position of the shift register will be flipped. The scaling on the potentiometer is from p=0 at the extreme counterclockwise position, up to p=0.125 at about the 4 o/clock position. Turning the knob all the way clockwise (to 5 o'clock) forces the probability to 1.0, (that is, every bit is flipped at every step), thus turning the shift register into a Moebius strip and effectively doubling its length (to a maximum of 64 steps). In general, low settings work best, and the shorter the length of the shift register, as set by the Length knob (the 3rd knob), the lower the Probability setting needs to be in order to maintain a given rate (strictly, expectation) of a bit being flipped in any arbitrary time period. Remember, the probability is tested at every step of the shift register, so if you only want a bit to be flipped every few cycles of the register, you will need a quite low per-shift probability. In general, low probabilities are the sweet spot.
• Span - sets the span (or range) of CV output by the Turing Machine, from a minimum of 0 volts to 0 volts (that is, no change at all) up to a span of about 0 to 5 volts. A low span compresses the range of the control voltage output. Note that the voltage is unquantised, and thus for best effect when used to control pitch of an oscillator, you really need to feed it through a voltage (note) quantiser (such as one of these, or these), or use it with an oscillator module that has built-in note quantisation, such as Braids (or Braids running Bees-in-the-Trees alternative firmware for even more quantisation options). Smaller spans create a more restrained, sombre feel to the sequence, while longer spans sound livelier and more bouncy, but it is easy to go too far with the span. Very short note spans can be effective when used with heavy timbral and/or colour modulation.
• Length - sets the length of the shift register, in 4 bit steps from 8 bits at the extreme anticlockwise position, to 32 bits at the extreme clockwise position. The length of the shift register in bits controls the number of steps before the pattern loops around and repeats (subject to random change as set by the Probability pot).
• Clock Division - sets the clock division ratio for the incoming trigger (clock), from a minimum of 1 at the extreme anti-clockwise position, to a maximum of 8 at the extreme clockwise position. Thus, when set to 1, the Turing Machine shift register will advance one step every time a trigger is received. If set to 2, then the shift register only advances every second trigger, and so on.

In SPLIT mode, the knobs from top to bottom control:

• Channel 1 Probability
• Channel 1 Span
• Channel 2 Probability
• Channel 2 Span

Note that in SPLIT mode, Length defaults to 8 and Clock Division to 1, but if you set these in TWIN or EXPERT modes, then whatever you set for Length and Clock Division will be retained in SPLIT mode.

Installation

First of all, all of the warnings set out in the Bees-in-the-Trees documentation, here, also apply to Dead Man's Catch firmware for Peaks. Please read these warnings and pay heed to them. This is beta firmware, and in any case, no warranty or guarantee that it will work correctly is offered. If you are in doubt, do not install Dead Man's Catch!

If, after reading all the warnings, you still wish to proceed, then before attempting to install Dead Man's Catch, it is strongly recommended that you practice the firmware update procedure and establish that it works correctly by re-installing the official factory Peaks firmware. You can download the latest official peaks firmware from the Mutable Instruments official firmware repository (just scroll down the list to find the latest version of Peaks firmware, which will be version 1.0 or higher). Now just follow the instructions in the Firmware update procedure section of the official Peaks manual.

Once you have established that you are able to install the factory Peaks firmware successfully, just follow the same procedure but using the Dead Man's Catch firmware WAV file that you download below, rather than the audio firmware file for the official factory Peaks firmware. You will need to unzip the file before using it, using whatever unzip utility you usually use.

De-installation

If you want to revert to the official Peaks firmware, download the WAV file for the latest official release for Peaks from the Mutable Instruments official firmware repository, and follow the same firmware update procedure, as described in the Firmware update procedure section of the official Peaks manual, using the official Peaks firmware WAV file. Note that it is strongly recommended that you set your Peaks to standard ENV function in the base (non-alternative) mode, on both channels, before trying to re-install the official Peaks firmware. If you don't do that, it shouldn't matter, but it is a wise precaution.

Feedback

If you encounter any bugs, please report them to Tim Churches at [email protected] providing as much detail about how to reproduce the problem as possible. Buggy behaviour that can't be reproduced can't be fixed.

Future versions

More features will be added to Dead Man's Catch in due course, as time permits. There is no development or release timetable. Some ideas for what might be included can be found in the Mutated Mutables wiki. If you have a GitHub account, you may add your own suggestions and ideas to that wiki page, or you can email me at [email protected], or discuss them on the Mutable Instruments forum, where they will be noted and recorded on the wiki page if they are a good idea and potentially feasible.

Feel free to fork or clone this repository, and git pull requests are welcome.