EL - Euclidean Sequencer

(Documenation generated by ClaudeAI - please report any errors or inconsistencies)

The Euclidean Sequencer mode (EL) runs 8 independent Euclidean rhythm generators simultaneously. Each generator distributes a number of events (trigger hits) as evenly as possible across a number of steps, following the Bjorklund/Toussaint Euclidean algorithm. Each of the 8 channels outputs its own MIDI note with independent pitch, velocity, MIDI channel, timing, swing, and MidiFX routing.

The mode abbreviation for this mode is EL. Select it from the mode select screen by long-pressing the encoder.


Key Layout

[AUX ] [F1  ] [F2  ] [MIX ] [EDT ] [PAT ] [MFX1] [MFX2] [MFX3] [MFX4] [MFX5]
                      [EU1 ] [EU2 ] [EU3 ] [EU4 ] [EU5 ] [EU6 ] [EU7 ] [EU8 ]
Key(s) Action
AUX Toggle play / stop
F1 Hold: enter Mute mode — keys EU1–EU8 toggle per-channel mute
F2 Hold: enter Paste mode (Edit/Mix) or Save mode (Pattern)
F1 + F2 Both held = Cut mode — keys EU1–EU8 cut (copy + reset) a channel
Key 3 Switch to MIX param mode
Key 4 Switch to EDIT param mode
Key 5 Switch to PATTERN param mode
Keys 6–10 Select/assign the active euclid channel's MidiFX group (1–5)
Keys 11–18 Select / act on Euclidean channels EU1–EU8

Param Modes

Press keys 3, 4, or 5 to switch between three param modes. The mode key lights white when active.

MIX Mode (key 3)

A performance overview showing all 8 channels. Channels flash when triggered. Use F1-held to mute/unmute channels. MidiFX group selector (keys 6–10) is active.

LED colors in MIX mode: - Orange = channel active - Flash/pulse = channel just triggered a note - Very dark = channel muted

EDIT Mode (key 4) — default on entry

Edit all parameters for the currently selected channel. Select a channel with keys 11–18. Use the encoder to navigate parameter pages and adjust values.

LED colors in EDIT mode: - Light blue = selected channel - Dark red = other channels (unselected) - Amber = channel triggered (while playing) - Dark blue = channel muted

PATTERN Mode (key 5)

Save and recall complete snapshots of all 8 channel settings. 16 save slots, shown on keys 11–26.

  • Press a key → load that slot immediately
  • Hold F2 + press a key → save current state to that slot

The most recently loaded/saved slot is remembered across power cycles.


Selecting and Editing Channels

In EDIT or MIX mode, press any of keys 11–18 to select that Euclidean channel (EU1–EU8). The display and encoder will operate on the selected channel.

Use the encoder to navigate between parameter pages. Short press the encoder to toggle between page select mode (turn to change page) and value edit mode (turn to change the selected parameter's value).

Hold AUX and turn the encoder to quickly adjust the selected parameter without needing to press the encoder first.


Parameter Pages (EDIT Mode)

Page 0 — Pattern View (PAT)

Displays a graphical step-sequencer view of the selected channel's Euclidean pattern on the OLED. While playing, a playhead marker shows the current position. This page is read-only — navigate to Page 1 to edit pattern parameters.

Page 1 — Pattern Parameters

Display Parameter Range Description
ROT Rotation 0–32 Shifts the pattern start position (rotates which step the first hit lands on)
EVTS Events 0–32 Number of trigger hits in the pattern
STEPS Steps 0–32 Total length of the pattern in steps
LEN Note Length 0–9 Duration of each triggered note (see Note Lengths table below)

Note Lengths:

Index Step Length
0 0.10
1 0.25
2 0.50
3 0.75
4 1.00
5 1.50
6 2.00
7 4.00
8 8.00
9 16.00

Setting STEPS to 0 disables the channel. Setting EVTS to 0 produces a pattern of all rests (no triggers). Setting EVTS equal to STEPS produces a pattern of all hits.

Page 2 — Note Parameters

Display Parameter Range Description
NOTE Note Number 0–127 MIDI note number to send when triggered
CHAN MIDI Channel 1–16 MIDI channel to send on
VEL Velocity 0–127 Note velocity
SWNG Swing 0–100 Swing amount — delays even-numbered steps (see Swing)

Default note assignments:

Channel Default Note GM Drum Equivalent
EU1 36 Bass Drum
EU2 38 Snare
EU3 42 Closed Hi-Hat
EU4 46 Open Hi-Hat
EU5 60 C4
EU6 64 E4
EU7 67 G4
EU8 71 B4

Page 3 — Config

Display Parameter Range Description
MODE Rhythm Mode 0 / 1 0 = PolyMeter, 1 = PolyRhythm (global setting, applies to all channels)
TRAT Track Rate 0–6 Clock multiplier/divider for the selected channel
PRAT PolyRhythm Rate 0–6 Global clock multiplier for PolyRhythm mode (applies to all channels)
BPM Tempo 40–300 Internal clock tempo in BPM

Clock Multiplier / Divider values:

Index Multiplier
0 ÷4 (0.25×)
1 ÷2 (0.5×)
2 ×1 (1×)
3 ×2
4 ×4 (default)
5 ×8
6 ×16

Pot Assignments (EDIT Mode)

Pot Parameter Range
1 Rotation (ROT) 0–32
2 Events (EVTS) 0–32
3 Steps (STEPS) 0–32
4 Note Length (LEN) 0–9
5 Track Rate (TRAT) — or global PolyRhythm Rate (PRAT) when in PolyRhythm mode 0–6

PolyMeter vs PolyRhythm

The global MODE setting (Page 3, param 1) controls how all 8 channels relate to each other rhythmically.

PolyMeter (MODE = 0, default)

Each channel advances one step per clock tick, scaled by its Track Rate (TRAT). All channels tick at the same underlying rate, but because they have different step counts they cycle at different lengths. This causes patterns to drift in and out of phase over time — the classic polymetric effect.

Example: A 3-step pattern and a 5-step pattern both running at 1× will cycle every 3 and 5 steps respectively, realigning every 15 steps.

PolyRhythm (MODE = 1)

Each channel's step interval is calculated so that it completes one full cycle per bar, regardless of how many steps it has. The formula is:

step_interval = (clock_step × 16 / steps) × PolyRhythm_Rate

More steps means more hits within the same bar — it changes the density of the rhythm. All channels stay phase-locked to the same bar length. Use the global PolyRhythm Rate (PRAT) to scale all channels up or down in tempo together.


Swing

When SWNG is greater than 0, every even-numbered step (steps 0, 2, 4…) is delayed by a time offset proportional to the swing value.

  • Values 1–98: Fixed swing — larger values push even steps further behind the beat
  • Value 99: Drunken swing — each even step gets a random swing offset between 1–95, creating a loose, humanized feel

Swing interacts with the channel's Track Rate multiplier. Swing is per-channel and is saved with the channel settings.


MidiFX Routing

Each channel can be routed to one of 5 MidiFX groups (keys 6–10). MidiFX groups are shared signal chains — think of each group as a pedalboard for MIDI: notes enter from one end, pass through up to 8 effect slots, and exit the other end before being sent to MIDI output.

Keys 6–10 colors: - Cyan = MidiFX group currently assigned to the selected channel - Blue = other groups

Assigning a MidiFX group: - Press keys 6–10 to assign the selected channel to that group

Editing a MidiFX group: - Double-tap or hold keys 6–10 to enter that group's editor

Different channels can share the same MidiFX group, or each channel can have its own.

See the MidiFX documentation for details on available effects (arpeggiator, etc.).


Copy / Paste / Cut

These operations copy all per-channel settings (steps, events, rotation, note, velocity, etc.) between channels.

Gesture Action
Press a channel key (EU1–EU8) Select that channel; its settings are auto-copied to clipboard
Hold F2 + press a channel key Paste — apply clipboard settings to that channel
Hold F1+F2 + press a channel key Cut — paste clipboard to that channel, then reset source to defaults

A display message confirms paste and cut operations.


Mute

Any channel can be silenced without stopping its internal clock position.

  • Hold F1 + press EU1–EU8 → toggle mute on that channel
  • In MIX mode: pressing EU1–EU8 selects and toggles mute simultaneously
  • Muted channels still advance their step position internally — they just don't send notes
  • Mute state is saved with each pattern slot

LED colors for muted channels: - EDIT mode: very dark blue - MIX mode: very dark (near-off)


Save / Load Patterns

16 save slots each store all 8 channel settings plus the global PolyMeter/PolyRhythm mode.

Switch to PATTERN mode (key 5). Keys 11–26 represent slots 1–16. The currently loaded slot lights white; others light dark green.

Action Result
Press a slot key Load that slot
Hold F2 + press a slot key Save current state to slot

Patterns are saved to persistent storage (FRAM/EEPROM) and survive power cycles. The last loaded slot is automatically restored on startup.


MIDI Clock

The Euclidean Sequencer responds to incoming MIDI clock transport messages, allowing it to sync to an external DAW or clock source:

MIDI Message Behavior
Start Resets all 8 channels to step 0 and starts playing
Stop Stops all channels and silences any held notes
Continue Resumes all channels from their current positions

When running from the internal clock, AUX starts and stops playback and sends MIDI clock output.


How Euclidean Patterns Work

A Euclidean pattern of E events over S steps distributes E hits as evenly as possible through S positions. For example:

Events (E) Steps (S) Pattern
1 4 X - - -
2 4 X - X -
3 8 X - - X - - X -
5 8 X - X X - X X -
3 7 X - X - X - -

Rotation then offsets the start of the pattern. A rotation of 1 shifts everything one step to the right:

E=3, S=8, ROT=0:  X - - X - - X -
E=3, S=8, ROT=2:  - X - - X - - X

Patterns can be up to 32 steps long. All 8 channels run their patterns independently.


LED Quick Reference

LED Position Meaning
AUX (key 0) Blinking lime green = sequencer playing
F1 (key 1) Lit = F1 held (Mute mode active)
F2 (key 2) Lit = F2 held (Paste/Save mode active)
F1 + F2 Both blinking = Cut mode active
Key 3 White = MIX mode active; Orange = inactive
Key 4 White = EDIT mode active; Dark red = inactive
Key 5 White = PATTERN mode active; Dark green = inactive
Keys 6–10 Cyan = active MidiFX group; Blue = others
Keys 11–18 Channel status color (see per-mode color table)