24.April.2018
Mutant Brain user manual v1.00
PG7
Hexinverter Électronique, 2018
Layout of the configuration page
The function for each control will be explained in the following sections, however at a basic level the
configuration page has the following sections:
1.
At the top are the controls that allow you to load an existing SysEx file into the page
2.
Below this are Global settings which define some optional standard values for other mappings (such
as the MIDI channel).
3.
The four “note inputs” which listen to incoming MIDI notes and deal with prioritizing them and
assembling them into chords which can be mapped to CV and Gates outputs – these will be
explained next
4.
The source of the voltages for each of the four CV outputs
5.
The source of the status for each of the twelve gate outputs
BASIC SETUP
The note inputs
The Note Inputs dropdown on the Mutant Brain Surgery page need some explanation. A key point to
remember is that a musical note (but not a drum trigger) can only be mapped to a CV output if it has come
through a “Note Input”. We cannot simply map a MIDI note to a CV output.
What is this note input and why is in needed?
Many, if not most, modular users do not use a keyboard to sequence notes, but the MIDI standard is partly
geared towards keyboard players and the Note Input allows Mutant Brain to take advantage of MIDI’s
performance-oriented features, as well as allowing polyphonic sequencing.
Say you want to play a mono keyboard patch over MIDI. If you play notes one at a time this works - the synth
plays each note we press. However, what if you press more than one note at a time? A monosynth played via
MIDI must decide to play just one of the notes you are holding, and when you release that note it may
(depending on what synth you have) start playing one of the other notes that is also held. This “prioritisation”
of the notes is a useful feature for keyboard players and can be used to get some nice trills or alternating
lead and bass notes.
Mutant Brain must make the same decision, so it needs to “listen” for the MIDI notes and decide which note
to send to the CV output. This is where “Note Inputs” come into play - they prioritise the notes and decide
which one should be mapped to a CV out. For polyphonic modes there might be multiple CV outputs playing
the notes, so the Note Input must be separate from the CV output itself.
Basic note mapping
Say we have a mono patch that we want to control with MIDI notes on MIDI channel #1. We are using a MIDI
sequencer - no two notes will ever be played at the same time, so it does not matter what the note priority is
set to.
