Westlicht PERFORMER User manual

westlicht PER|FORMER
USER MANUAL
This document is written for firmware version 0.1.40

Table Of Contents
Introduction
Overview
Concepts
Project
Track
Note Track
Curve Track
MIDI/CV Track
Pattern
Snapshot
Fills
Song
Scale
Clock
Routing
Controller
File Management
User Interface
Overview
Navigation
Page Layout
List Pages
Copy/Paste
Pages
Project
Layout
Track
Sequence
Steps
Song
Tempo
Pattern
Performer
Routing
Midi Output
User Scale
Overview
Monitor
Clock
System
Appendix
Recording
Divisors
Run Modes
Play Modes
Rotation
Step Conditions
Scales
Shapes
Arpeggiator Modes
Routing Targets
Launchpad
USB MIDI Devices
Calibration Procedure

Firmware Update

Introduction
PER|FORMER is an open source and open hardware eurorack sequencer module. It packs a lot of functionality into a small
form factor and was designed both as a versatile sequencer in the studio as well as for live performance. To fully take
advantage of all the features available in this module, it is highly recommended to study this document carefully.
The Concepts chapter introduces the overall architecture and functionality of the sequencer. The User Interface chapter gives
an overview of the user interface and introduces key concepts of how to use the sequencer. The Pages chapter goes into more
detail in terms of functionality and user interface of the various modes and contexts in the sequencer and introduces common
workflows. Finally, the [Appendix][#appendix] contains reference tables for some of the parameters commonly used in the
sequencer as well as additional information on how to use the Novation Launchpad, calibrate the CV outputs and update the
firmware.
Overview
Here is a brief summary of what you get with the PER|FORMER sequencer.
Features
8 track sequencer
16 sequences per track
64 steps per sequence
Multiple track and sequence modes
Note and modulation sequencing
Arpeggiator
Snapshot system
Sequence generators
Routing system for CV inputs and external MIDI controllers
Novation Launchpad support
Generate MIDI output from multiple sequences
Flexible clock system

User Interface
Large and bright 256x64 pixel OLED display
Encoder with push button
32 buttons with bi-color LEDs
5 function buttons with labels on display
Inputs and Outputs
8 CV outputs (-5V to 5V)
8 gate outputs (5V)
4 CV inputs (-5V to 5V)
Clock and reset/run input
Clock and reset/run output
MIDI input and output (MIDI TRS 3.5mm jacks)
USB Host for MIDI over USB
microSD Card Slot
Specifications
Width: 34 HP
Depth: 25mm
Power: 100mA @ +12V, 15mA @ -12V (not including USB host power)

Concepts
This chapter introduces the basic concepts of the sequencer and should familiarize readers with the overall functionality of the
sequencer. More in-depth information about specific features are provided in the following chapters.
Project
A project represents the complete state of the sequencer, with the exception of calibration data. Only one project can be loaded
at any given time and all data is volatile, meaning that all changes are lost when the unit is powered off. To persist a project it
needs to be stored to the SD card (see Project page).
Projects are split into two data regions. The first region contains all the global data such as project settings, layout settings,
MIDI output settings, routing settings, song data and play state. The second region contains the data for the 8 tracks, where
each track contains the track settings and 16 sequences. Each sequence in turn contains the sequence settings and up to 64
steps.
Note: Calibration data is stored in the flash memory of the micro controller and can be backed up
and restored from the SD card. This allows exchanging the SD card while running the sequencer
or run the sequencer without an SD card at all and still have it properly calibrated.
Track
A track is responsible for generating note or modulation signals used to control other modules in the eurorack system using the
CV/gate outputs. The PER|FORMER sequencer can run up to 8 tracks, that primarily use step sequencing to generate these
signals, where each track can run independent of the other tracks. This means that every sequence in a track can have a
different time division, run mode, duration or scale among other properties.
Track Mode
Each of the 8 tracks can be configured to one of the following modes:
Note
Curve
MIDI/CV
In Note mode, the default mode, a track uses advanced step sequencing to generate rhythms and melodies. Curve mode also
uses step sequencing, but each step is defined as a curve shape, making this mode very versatile for generating modulation
signals. In MIDI/CV mode, a track acts as a MIDI to CV converter, which can be useful when attaching a MIDI keyboard to play
some voices live or sequence them from an external MIDI sequencer.
Track Routing
In the default configuration, each track controls one of the CV/gate output pairs of the sequencer to control a single voice.
However, this configuration can be changed to allow for more flexible routing of the virtual track outputs to the physical CV/gate
outputs. For example, a MIDI/CV track can control more than one physical CV/gate output to allow polyphonic operation or
output a velocity signal in addition to the pitch signal.
Track Linking
In Note or Curve mode, a track generates a single CV signal, typically a pitch or modulation signal. To control a voice with
multiple signals, for example a pitch and velocity signal, two tracks have to be used in combination. The first track is used to
generate the pitch signal while the second track generates the velocity signal. Using two tracks allows to use different sequence

lengths, time divison and other properties that affect playback. If that is not desired, the second track can be linked to the first
track, essentially doubling the playback behavior.
Track modes, the physical routing to CV/gate outputs and track linking can be configured on the Layout page.
Note Track
By default, all tracks are configured as note tracks. In this mode, the track uses step sequencing to generate gate and CV
signals. A sequence consists of a maximum of 64 steps and there is a total of 16 sequences per track.
Each step is defined through a number of properties, also called layers, to control the generated gate and CV signals.
The Gate layer defines what steps of the sequence create a gate signal. To introduce some random variation, the Gate
Probability layer is used to control how often an active gate is actually generated.
The Gate Offset layer is used to offset gate signals into the future, adding a delay before triggering a note.
The Length layer controls the duration of the gate signal and allows to tie notes together if set to the maximum. Again, to
introduce some random variation, the Length Variation Range and Length Variation Probability layers control a maximum
random deviation of the gate length and the probability of actually randomizing the gate length.
The Retrigger layer allows each gate signal to be retriggered multiple times within the duration of the step, allowing for faster
gates and ratcheting effects. Retriggered notes are only output within the current Length of the step. This allows to output a
burst of notes only at the beginning of the step. Retriggering can also be randomized using the Retrigger Probability layer.
The generated CV signal is controlled by the Note layer, which basically defines the voltage to be output for each step. Each
note is stored as an index to an entry in a Scale, allowing the generated CV signals to be used both for controlling note pitch as
well as other arbitrary modulation signals. Using the Note Variation Range and Note Variation Probability layers some random
variation can be applied to the CV signal. The Slide layer controls if the generate CV signal is changed immediately on the start
of a gate or smoothly slides to the new voltage.
Finally, the Condition layer is used to conditionally trigger steps based on certain rules. This allows to create relatively short
sequences that feel more complex, for example by only playing steps every few iterations. See Step Conditions for additional
information.
The playback of the sequence is controlled by additional parameters:
Divisor controls the rate at which steps are played back
Run Mode controls the order in which steps are played back
First Step and Last Step control what range of the sequence is played back
Sequences are edited on the Steps page and sequence parameters can be edited on the Sequence page.
Curve Track
In Curve mode, a track also uses step sequencing with similar playback features to the note track. However, in this track mode
the CV signal is defined by a series of curve shapes, making this mode useful to generate modulation signals. This mode also
allows to output gate patterns, but it is different from how the Note mode works.
The generated CV signal is controlled by the Shape layer, which defines a curve shape to be output over the duration of one
step. The Minimum and Maximum layers define the lower and upper voltage that is output for each step. To introduce some
random variation, the Shape Variation and Shape Variation Probability layers can be used to define altered shapes that are used
instead of the primary shape with some probability.
The generated gate signal is controlled by the Gate layer. It allows to define a pattern of up to 4 gate triggers per step. To
introduce some random variation, the Gate Probability layer is used to control how often a gate is actually played.

The playback of the sequence is controlled by the same set of parameters as in the note track.
MIDI/CV Track
In MIDI/CV mode, a track acts as a MIDI to CV converter, taking MIDI note data from either the MIDI or USBMIDI input and
converting it to voltages at the CV/gate outputs. This allows for playing voices live from a keyboard or use an external MIDI
sequencer to control them. MIDI/CV mode also provides a powerful arpeggiator to further help playing live.
Note: MIDI/CV mode allows for using the PER|FORMER module as a pure MIDI/CV converter
with up to 8 CV/Gate outputs.
Pattern
In Note and Curve mode, each of the 8 tracks contains up to 16 sequences, also referred to as patterns. During playback, each
track is playing one of its 16 patterns. When switching patterns, all tracks can be switched to the same pattern number or
specific patterns can be selected for individual tracks. Patterns are controlled from the Pattern page.
Snapshot
In addition to the 16 patterns per track, there is an additional snapshot pattern which can temporarily be used to edit
sequences without affecting the original. When taking a snapshot, all patterns that are currently playing in each track are copied
to the snapshot. Snapshots come in handy during live performance for quickly changing sequences on the fly. The changes can
later be committed or reverted. Snapshots are controlled from the Pattern page.
Fills
Fills can be used as an effective tool during live performance. They allow to temporarily change the playback of a sequence to
add some variation or tension. Each track can be configured with a specific fill mode. The default mode will simply trigger every
step of a sequence no matter if the gate is enabled or disabled. Other fill modes allow to temporarily play steps from the next
sequence or trigger steps that have the Fill condition set. To make things more interesting, each track also has a Fill Amount
associated which is a probability value that controls how often a step is affected by the selected fill mode. This for example
allows to morph between two patterns by selectively playing a given amount of steps from either pattern. Fills can then be
controlled from the Performer page.
Song
Songs are used to chain together a sequence of patterns for each track. This can either be used to quickly chain together
patterns during a live performance to get more variation or to create an entire arrangement of a song.
A song consists of up to 64 slots, each holding a set of patterns to be played on the 8 tracks in addition to specifying for how
many bars/measures the slot is played for. Songs are controlled from the Song page.
Scale
In contrast to many other sequencers that directly operate on chromatic note values, the PER|FORMER sequencer is using the
concept of voltage tables. Each note is stored as an index into a voltage table that does not necessarily have a specific musical
meaning. While offering many of the more commonly used scales in form of presets, the sequencer also provides some scales
beyond the typical western chromatic variants, for example a 24 tone equal temperament scale. The additional 4 user scales
allow for even more experimentation as well as setting up voltage tables to specifically address discrete values of a CV input on
another module. This allows for example to select a specific sample slot, choose a wavetable or similar applications.
A global default scale and root note can be specified on the Project page which can be overridden for individual sequences in
the Sequence page. The user scales can be edited on the User Scale page. See Scales appendix for a list of all preset scales.

Clock
The sequencer is driven by a flexible clock system. In master mode, the clock is generated internally and can be sent to
external gear and modules using MIDI clock and analog clock signals. In slave mode, the clock is received from an external
source via MIDI or analog clock signals. For convenience, the clock is set to an auto mode by default that automatically
switches to master mode when the sequencer is started manually or switches to the slave mode when an external clock signal
is detected.
To allow for accurate timing, the internal clock is running at a resolution of 192 parts per quarter note (PPQN). In master mode, a
hardware timer is used to generate a low-jitter clock signal. To drive external clock signals, the internal clock is divided down to
the required PPQN of the external clock signals. In slave mode, the external clock signal is multiplied internally to generate the
192 PPQN internal clock resolution, which in turn is used to clock the sequencer as well as the external clock signals.
The clock system is configured on the Clock page.
Routing
Many of the parameters in the sequencer can be controlled from external signals. This is useful for both experimentation and for
controlling the sequencer with additional controllers in a live performance. The following sources can be used in the routing
system:
4 CV inputs
8 CV outputs (allows for cross modulation without patching)
MIDI controllers (pitch bend, controller change, individual notes)
Each route is a mapping from a source signal to a parameter, including a mapping of the source range to a parameter range.
For example, an external CV signal can be mapped to the master clock tempo such that -5V - +5V maps to 100 - 140 BPM.
The routing system also implements a MIDI learn function, which allows to easily map MIDI controllers to specific parameters.
Routes can be created and edited on the Routing page.
Controller
In addition to the routing system, specific MIDI controllers such as the Novation Launchpad can be used to control many
aspects of the sequencer. This includes editing sequences, controlling mutes, launching patterns among other things.
Note: Launchpad is currently the only supported controller but others may follow.
See Launchpad for more details.
File Management
The SD card can be used to store various resources such as projects, user scales and system settings. Resources are stored
into slots, with each type having a total of 128 slots available. The actual content on the SD card looks as follows:
PROJECTS/
001.PRO
002.PRO
…
SCALES/
001.SCA
002.SCA
…
SETTINGS.DAT

where 001.PRO is the first project slot, 002.SCA is the second user scale slot and SETTINGS.DAT is the backup of the system
settings (also stored in on-chip flash memory).
The reason for using a slot system rather than traditional filenames is in order to allow for a smooth user experience while
preserving the limited resources on the system.
Note: The SD card can easily be backed up to a computer by just copying the files. Slots can
freely be rearranged by just renaming the files.

User Interface
Overview
The user interface of the PER|FORMER sequencer is made up from the following components:
OLED display
Rotary encoder with button
5 function buttons
32 buttons with bi-color LEDs
The rotary encoder will furthermore be denoted as ENCODER. The buttons are split into 4 groups:
Function Buttons
There are 5 function buttons below the display: F1, F2, F3, F4 and F5. The function associated with each button
depends on the currently selected page and context. However, due to each function button being dynamically labeled on the
display, its always easy to see what the associated functions are.
Global Buttons
There are 8 global buttons: PLAY, TEMP, PATT, PERF, PREV, NEXT, SHIFT and PAGE.
All global buttons have fixed functions associated to them:
Button Function
PLAY Starts/stops the master clock.
SHIFT + PLAY Pause/continue or restart master clock depending on the configured Shift Mode on the Clock
page.
PAGE + PLAY Enable/disable recording mode.

Button Function
TEMP Shows the Tempo page while being hold.
PATT Shows the Pattern page while being hold.
PERF Shows the Performer page while being hold.
PREV, NEXT Navigate on a page, depends on current context.
SHIFT Enable alternate function, depends on current context.
PAGE Switch between pages.
SHIFT + PAGE Show context menu for the active page.
Track Buttons
There are 8 track buttons: T1 to T8. These buttons are generally used to select the active track, but also to select pages in
combination with the PAGE button and some other functions depending on the active page.
Step Buttons
There are 16 step buttons: S1 to S16. These buttons are generally used to select steps in a sequence, but also to select
pages in combination with the PAGE button and some other functions depending on the active page.
Navigation
The user interface is organized in multiple pages, each page giving access to a different part of the sequencer such as:
Editing configuration options
Editing sequences and steps
Performance related functions such as tempo, muting or pattern selection
Displaying various other information
The active page is selected by holding the PAGE button and pressing the corresponding page button:
Button Page
PAGE + CLOCK ( TEMP)Clock
PAGE + PATT Pattern
PAGE + PERF Performer
PAGE + PROJECT ( T1)Project
PAGE + LAYOUT ( T2)Layout
PAGE + ROUTING ( T3)Routing
PAGE + MIDIOUT ( T4)Midi Output
PAGE + U.SCALE ( T5)User Scale
PAGE + STEPS ( S1)Steps
PAGE + SEQ ( S2)Sequence

Button Page
PAGE + TRACK ( S3)Track
PAGE + SONG ( S4)Song
PAGE + MONITOR ( S8)Monitor
PAGE + SYSTEM ( T8)System
PAGE + PREV Overview
There are 3 special pages which can be entered temporarily by just holding a single button, namely the Tempo, Pattern and
Performer pages. These pages give access to performance related features which need to be quickly accessible at any time.
Note: While holding PAGE, the LEDs are used to indicate the currently selected page as well as
marking the buttons associated with a page.
Page Layout
Pages are divided into three sections.
Header
The header is used to display the global state of the sequencer and information about the active page and context.
The current clock mode and tempo are shown in the top-left corner. The clock mode can by any of the following:
A Auto
M Master
S Slave
Instead of showing the clock mode, R is displayed when recording is enabled.
The currently selected track is shown as T1 - T8. The currently playing pattern on the selected track is shown as P1 - P16. If a
song is currently playing, the playing pattern is highlighted. The currently edited pattern is shown as E1 - E16 and is highlighted
if it matches the pattern that is currently playing. If a snapshot is currently active, the pattern info is replaced with a single item
SNAP.
The currently active page is shown in the top-right corner and optionally a sub-page or mode is shown to its left.
Body
The body is used to display the main content for the active page.

Footer
The footer is used to display the labels of the function buttons for the current page.
On pages such as the Layout page, the function buttons are used to switch between different sub-pages. In that case, the
currently active sub-page is highlighted in the footer.
On pages that provide a context menu, the labels dynamically change to the context menu actions when SHIFT + PAGE is
hold.
List Pages
Pages that expose configuration options are typically presented as a list of items, each having the name shown on the left and
the value on the right side.
Rotate the ENCODER or use PREV, NEXT to navigate up and down the list. Press ENCODER to enter and leave edit mode
which is indicated by moving the highlight from the item name to the item value and back. While in edit mode, rotate the
ENCODER or use PREV, NEXT to adjust the value. Hold SHIFT to change the value in larger or smaller steps depending on
the item being edited.
Copy/Paste
To allow moving and copying data, a copy/paste system is implemented that allows acting on the following types of objects:
Track (see Track page)
Sequence (see Sequence page)
Steps (see Steps page)
Pattern (see Pattern page)
User Scale (see User Scale page)
Copy/paste actions are provided in the context menu when holding SHIFT + PAGE.

Note: Due to memory limitations, the clipboard can only hold one object at a time and shares
memory across all different types. This means that copying an object always results in the
previously copied object being cleared from the clipboard.

Pages
Project
The Project page is entered using PAGE + PROJECT.
This page allows to change project wide parameters as well loading and saving projects from/to the SD card.
Parameters
The following parameters are available:
Parameter Range Description
Name - Press ENCODER to enter text editor for changing the project name.
Tempo 1.0 - 1000.0
BPM Tempo of the master clock.
Swing 50% - 75% Global swing amount.
Time
Signature Beats/Note
Time signature defining the musical measure/bar length for Sync Measure and Reset
Measure on sequences. The time signature is also used to define the length of a bar in
song mode.
Sync
Measure 1 - 128 bars Multiple of measures/bars at which to execute syncing (see Pattern and Performer
pages).
page).
Scale Scales Default scale. Can be overwritten per sequence on the Sequence page.
Root Note
C, C#, D, D#,
E, F, F#, G,
G#, A, B
Default root note. Can be overwritten per sequence on the Sequence page.
Monitor
Mode
Always,
Stopped, Off
Live monitoring mode. Always enables monitoring always, Stopped only if clock is
stopped and Off disables it.
Record
Mode
Overdub,
Overwrite,
Step Record
Recording mode (see Recording).
MIDI Input Off, All, MIDI,
USB Select MIDI input for monitoring and recording.

Parameter Range Description
CV/Gate
Input
Off,
CV1/CV2,
CV3/CV4
Enable CV/Gate input on CV inputs for monitoring and recording (emulating a MIDI
keyboard).
Curve CV
Input
Off, CV1,
CV2, CV3,
CV4
Select CV input for curve recording.
Note: Tempo and Swing are routable parameters.
Context Menu
Hold SHIFT + PAGE to open the context menu and access the following functions:
Button Function Description
F1 Init Initialize the project to its default state. This will revert all unsaved changes.
F2 Load Load a project from the SD card.
F3 Save Save the project to the SD card and automatically overwrite the previous slot.
F4 Save As Save the project to a new slot on the SD card.
F5 Route Show existing or create a new route for the currently selected parameter (only active if
selected parameter is routable).
Note: Should you ever get bored sequencing, take a break and hit PAGE + S16.
Layout
The Layout page is entered using PAGE + LAYOUT. This page has 4 tabs accessed through F1, F2, F3 and F4.
Track Mode
The first tab is used to configure the track mode of each track.
Changing track mode results in all data associated with a given track to be erased. Because of this, when setting a new track
mode, it only takes effect after manually committing the change by pressing F5.

Link Track
The second tab is used to setup track linking. Each of the 8 tracks can be linked to any of the preceding tracks, taking over its
playback behavior.
Note: A track can only be linked to a preceding track due to the internal architecture of the
sequencer. This means that track 1 cannot use track linking, while track 2 can only be linked to
track 1. Track 8 on the other hand can be linked to any of the tracks 1-7.
Gate Output
The third tab is used to setup the mapping of virtual track gate outputs to the physical gate outputs. In default state, each track
is linked to the corresponding gate output with the same number.
CV Output
The fourth tab is used to setup the mapping of virtual track CV outputs to the physical CV outputs. In default state, each track is
linked to the corresponding CV output with the same number.

If using a MIDI/CV track, it can be useful to map multiple virtual outputs of the track to physical outputs to allow for polyphonic
signals or add modulation signals such as velocity or aftertouch. The following shows a configuration with two note polyphony
and pitch/velocity signals.
Track
The Track page is entered using PAGE + TRACK.
This page allows to change track wide settings. Note that the shown parameters depend on the configured Track Mode of the
selected track. Press T[1-8] to change the selected track.
Context Menu
Hold SHIFT + PAGE to open the context menu and access the following functions:
Button Function Description
F1 Init Initialize the selected track and all its content to the default state.
F2 Copy Copy the selected track and all its content to the clipboard.
F3 Paste Paste the clipboard to the selected track.

Button Function Description
F4 Route Show existing or create a new route for the currently selected parameter (only active if
selected parameter is routable).
Note Track
If a track is in Note mode, the following parameters are available:
Parameter Range Description
Play Mode Play
Modes Mode used for playing sequences in this track.
Fill Mode
None,
Gates,
Next
Pattern,
Condition
Mode used when fill is activated for the track. None does nothing. Gates plays each step
of the sequence independent of whether the step gate is active or not. Next Pattern uses
the step data of the next pattern on the same track. Condition plays steps that have the
Fill condition set, and does not play steps that have the !Fill condition set.
CV Update
Mode
Gate,
Always
Mode used for updating the CV output of this track. Gate only updates the CV output if
the step gate is active, Always always updates the CV output independent of the step
gate.
Slide Time 0% -
100% Duration of pitch slides for steps that have Slide enabled.
Octave -10 - +10 Number of octaves to transpose the sequence up or down.
Transpose -100 -
+100
Number of notes to transpose the sequence up or down. Note that this depends on the
current Scale of the sequence.
Rotate Rotation Amount of rotation applied to the sequence.
Gate P.
Bias
-100% -
+100% Gate probability bias that is added to the sequence.
Retrig P.
Bias
-100% -
+100% Retrigger probability bias that is added to the sequence.
Length
Bias
-100% -
+100% Length bias bias that is added to the sequence.
Note P.
Bias
-100% -
+100% Note variation probability bias that is added to the sequence.