Skip to content

Catalyst VoltSeq

github-actions[bot] edited this page Jun 24, 2026 · 5 revisions

Catalyst VoltSeq

Catalyst VoltSeq is a second firmware personality for the Catalyst Sequencer panel. It turns the module into an 8-channel voltage recorder and step sequencer, similar to Voltage Block. Each of the 8 outputs is an independent channel with its own step data, type, length, clock division, direction, and more.

Firmware variant: Catalyst VoltSeq is a separate build (catalyst-vX.Y.Z-catseq-voltseq.wav). Load it via the audio-cable bootloader. The CatSeq+CatCon build is a separate file.


Design Philosophy

Catalyst VoltSeq is a parameter lock style sequencer — every step stores its own independent value, and every channel can have its own type, length, clock division, and direction. This is closer in spirit to Elektron-style step programming than to a traditional sequencer where all channels share a common clock and length.

The design is an homage to the Malekko Voltage Block workflow: arm a channel, move a fader, and the module captures what you played. Catalyst VoltSeq extends that foundation with secondary step editing (per-step encoder editing while armed), stochastic randomness (per-step probability that affects whether or how much a step deviates), and polyrhythmic capabilities (independent channel lengths, divisions, and directions that let channels drift naturally in and out of phase).


Conventions

Modals

Channel Edit, Global Settings, Performance Page, and Clear Mode are modals — editing layers that temporarily take over the UI. While any modal is active:

  • Entry combos for other modals are silently ignored — exit the current modal first.
  • Play/Reset always exits. Playback state is preserved — playing stays playing; stopped stays stopped.
  • The one exception is Channel Edit, which can be entered while a channel is armed without first disarming.

If you are ever unsure what mode you are in, Play/Reset once returns you to the main mode.

Play/Reset is context-sensitive

Context Result
Main mode, no modal Toggle play/stop
Any modal active Exit modal (no playback change)
Channel armed Disarm (no playback change)

Saving

Catalyst VoltSeq uses intentional saving — no data is written to flash automatically (except Performance Page settings on exit). This means you can experiment freely: power-cycling without saving discards all changes. See the Saving section for the save gesture.


Hardware Overview

Catalyst VoltSeq uses the same physical panel as the Catalyst Sequencer. Panel controls are repurposed:

Physical control Function
Encoders 1–8 + jacks Channel outputs; encoders edit step values
Page buttons 1–8 Step select / channel arm / page nav (in editors)
Phase Scrub slider CV recorder input / Performance page orbit
Play/Reset Play/Stop; Shift+Play = Reset/Clear
Tap Tempo Tap tempo
Glide GLIDE modifier (hold for glide time / gate offset / pulse width)
Chan. Channel arm / Channel Edit
Shift Modifier; Shift+Chan. (hold 1 s) = Global Settings
Fine Fine-adjust modifier; Fine+Glide = Performance page / lock
Clock In External clock input
Reset jack Hardware reset trigger

The silkscreen Copy label (under Fine) is unused in VoltSeq. Copy is a Catalyst Sequencer feature only.


Switching Modes

Catalyst VoltSeq and CatSeq share the same panel and can be switched in software:

Sequencer → VoltSeq: Hold Shift + Tap Tempo + Chan. for 1 second. All 8 channel LEDs blink to confirm.

VoltSeq → Sequencer: Hold Fine + Play/Reset + Glide for 1 second. All 8 channel LEDs blink to confirm.

Switching does not erase the other mode's data.

Startup mode: The module does not automatically restore the last-used mode on reboot. To set which mode boots by default, power on while holding the mode-switch combo for that mode (hold until the LEDs blink to confirm).


Channels and Channel Types

Catalyst VoltSeq has 8 independent channels, each corresponding to one output jack and encoder knob.

Each channel has a type, set in Channel Edit (encoder 7):

Type Output Encoder LED
CV Stepped or slewed voltage, configurable range Scale color (see table below)
Gate Gate signal with variable length (0–100%) Dim green; brightness = gate length
Trigger Short trigger pulse with ratchet/repeat Green = ratchet, teal = repeat, off = rest

Default range for new channels is 0V to +5V (5V span, 0V transpose). Changing a channel's type does not erase its step data — the same stored values are simply interpreted differently by each type.

CV Quantizer Scales

The CV channel encoder LED color indicates the active quantizer scale. Chan. + Encoder N in main mode cycles channel N through its type and (for CV channels) scale.

LED Scale Notes
Dim grey Unquantized Continuous voltage, no snapping
Pink Chromatic All 12 semitones
Dim red Major W W H W W W H
Dim orange Minor W H W W H W W
Dim yellow Harmonic minor W H W W H A H
Dim teal Major pentatonic 5 notes
Dim blue Minor pentatonic 5 notes
Grey Wholetone 6 equal whole steps
Dim salmon Lydian dominant Major with ♯4 and ♭7
Dim lavender Bebop 8 notes
Very dim red Dorian Minor with ♮6
Very dim yellow Vietnamese 6-note anhemitonic
Very dim orange Yo Japanese 5-note
Very dim blue Blues 6 notes with ♭5
Very dim teal 21-TET Microtonal equal temperament
Various Custom 0–7 User-recorded scales (CatSeq only)

Clock

  • External clock: patch a signal into Clock In. The module locks to it automatically at 1 pulse per 16th note (16 PPQN). When the cable is removed, the internal clock resumes at the same tempo.
  • Internal clock: tap Tap Tempo to set BPM (first two taps are ignored; BPM updates on the third tap and beyond). Fine-tune BPM in Global Settings (encoder 6).
  • Reset jack: a trigger resets all channels to step 1 immediately and fires the first step's output, so the sequence is in sync from the moment the pulse arrives.

Main Mode

The main mode is Catalyst VoltSeq's default state — reached on boot, after disarming, or after exiting any editor. All other modes are entered from here and return here on exit. While in any modal editor (Channel Edit, Global Settings, Performance Page, Clear Mode), the entry combos for other modals are silently ignored — you must exit the current mode first. The only exception is Channel Edit, which can also be entered while a channel is armed.


General Operation

Play / Stop / Reset

Action Result
Play/Reset Toggle play/stop
Shift + Play (short tap) Reset all channels to step 1
Fine + Play (hold ~500 ms) Toggle Clear mode
Play/Reset while armed Disarm channel (playback continues)
Play/Reset while in any modal Exit modal (no playback change)

Clear Mode

From the main mode: hold Fine + Play/Reset for ~500 ms. Page button LEDs blink to confirm entry. Hold the same combo again to exit, or press Play/Reset alone.

Action Result
Page button N Clear steps + per-step glide + probability for channel N (preserves channel settings); CV steps → 0V, Gate/Trigger steps → off
Shift + Page button N Full factory reset for channel N — steps, per-step flags, and all channel settings; all steps → 0V / off
Play/Reset Exit Clear mode (no channels affected)

Multiple channels can be cleared before exiting — tap as many page buttons as needed, then press Play/Reset to return.

Page Navigation

Steps are organized into 8 pages of 8 steps per channel, giving 64 total steps per channel.

Shift + Page button N navigates to page N in every mode: normal, armed (any channel type), Channel Edit, and Performance Page.

While Shift is held (in normal or armed mode), the page buttons switch to a navigation indicator: the currently selected page button lights solid, and the encoder LED for the currently tracked channel blinks to confirm which channel's chaselight you are viewing. Pressing any page button in this state navigates without editing any steps.

Step Editing

Hold a Page button and turn an encoder to edit step values:

  • Encoder N sets the value for channel N at the held step.
  • Hold multiple Page buttons to edit the same position across multiple steps at once.
  • For CV channels: coarse ≈ 1 semitone per detent; hold Fine for sub-semitone. Fast spinning accelerates.
  • For Gate channels: adjusts gate length (0–100%). No acceleration.
  • For Trigger channels: adjusts ratchet/repeat count (±8). No acceleration.

Channels shorter than the current page wrap to their equivalent position — a Trigger channel with 8 steps will output its step 0 when you are editing page 2 step 1.

Chaselight

In the main mode (unarmed), the page button LEDs show the current playhead position for the most recently focused channel.

The tracked channel updates two ways:

  • Turn an encoder while holding a page button — edits a step and focuses that encoder's channel.
  • Turn an encoder without holding any page button — focuses that channel without editing anything. Use this to quickly aim the chaselight at any channel while playing.

Armed Mode

From the main mode: CHAN + Page button N arms channel N for focused editing. The encoder LED for that channel blinks. To disarm:

  • CHAN + same Page button N — disarm
  • Play/Reset — disarm without stopping playback

Armed CV Channel

The Phase Scrub slider records in real time:

  • While playing: slider value is written to the current step on every clock tick.
  • While stopped: slider continuously sets the last-touched step.

The slider maps across the channel's configured voltage window (Range + Transpose).

Each CV channel has a voltage window defined by two parameters:

  • Range — the span in volts: 1, 2, 3, 4, 5, 10, or 15V.
  • Transpose — the floor voltage in whole volts (e.g. −5V, 0V, +2V).

The window is [Transpose, Transpose + Range]. All recorded steps and all control input (slider, encoder in main mode) are relative to this window — moving the window transposes the whole sequence; narrowing it zooms the playable range.

Encoder LEDs: show the CV step color for each step on the current page. The playing step blinks (chaselight). The blink is suppressed on any held Page button so the color stays visible while editing.

Encoder N: directly edits step N's CV value. Fine = sub-semitone; fast spinning accelerates.

Glide held while armed: encoder LEDs switch to show per-step glide amounts (brightness = amount). Turn encoder N to adjust glide on step N; fully CCW = no glide.

Shift held while armed: all encoder LEDs go dark except enc 5 (Range) and enc 7 (Transpose). Inactive on Gate and Trigger channels.

Encoder Panel label Parameter
5 Range Voltage span: 2 / 5 / 10 / 15V — clamped; shifts sequence when changed
7 Transpose Floor voltage ±1V per detent, clamped to keep window within hardware limits

Shift + Glide held while armed: encoder LEDs switch to a violet → grey → white ramp showing the per-step randomness amount. Turn encoder N to set the probability of random deviation for step N (0 = never deviates, 100 = always deviates). See Per-Step Probability below.

Armed Gate Channel

Encoder LEDs: show each step's gate state. Playing step blinks (chaselight). While Glide is held, LEDs switch to show per-step ratchet counts (dim = no ratchet, bright green = high ratchet).

  • Tap a Page button → toggle step on/off (x0x)
  • Encoder N → adjust gate length for step N (0 = off, up to 100%)
  • Glide held + Encoder N → adjust ratchet count for step N (0 = single gate, 2–8 = fire N pulses per step, subdivided within the step period)

Shift + Glide held while armed: encoder LEDs switch to a violet → grey → white ramp showing the per-step randomness amount. Turn encoder N to set the suppression probability for step N (0 = always fires, 100 = never fires). See Per-Step Probability below.

Armed Trigger Channel

Encoder LEDs: show ratchet/repeat state. Playing step blinks (chaselight).

  • Tap a Page button → toggle step between rest and single trigger
  • Encoder N CW → increase ratchet count (subdivide; 1–8)
  • Encoder N CCW → increase repeat count (extend; negative values)

Shift + Glide held while armed: same probability editing as Gate. See Per-Step Probability below.


Per-Step Probability

Each step on each channel has an independent randomness amount (0–100), edited in armed mode via Shift + Glide + Encoder N.

The encoder LEDs switch to a violet → grey → white ramp while Shift + Glide are both held. Releasing either button reverts the display.

The randomness amount means different things by channel type:

Channel type 0 100 CW direction
CV Step always plays as recorded Step always applies a random deviation More deviation
Gate Step always fires Step is always suppressed More suppression
Trigger Step always fires (with all its ratchets) Step is always suppressed More suppression

For Gate and Trigger channels, suppression affects the entire step — all ratchets and repeats are suppressed together, not individually.

CV Deviation Amount

For CV channels, the deviation amount and type are set in Channel Edit, encoder 8:

Value Type Deviation range
CW from 0 (+N semitones) Unipolar Random offset in [0, +N/12] V upward from the recorded value
0 Off No deviation regardless of step probability
CCW from 0 (−N semitones) Bipolar Random offset in [−N/12, +N/12] V symmetric around the recorded value

Steps in semitones (±1 per detent), ±36 semitones (±3 octaves) maximum. The deviated value is clamped to the hardware output range, then quantized/scaled the same as the recorded step.

LED: light grey gradient (unipolar, non-octave); blue at octave values (12 / 24 / 36 semitones); salmon gradient (bipolar, non-octave); red at octave values (−12 / −24 / −36 semitones).


GLIDE Modifier

Hold Glide (unarmed) to access per-channel live parameters.

No page button held:

Encoder N CV channel Gate channel Trigger channel
Turn Glide time (0–10 s) Offset all gate lengths Trigger pulse width (1–100 ms)

Page button N held + Encoder M (Gate channel): set ratchet count for step N of Gate channel M.

Shift + Glide + Encoder N (Trigger channel): offset all ratchet/repeat counts for Trigger channel N.

CV glide time is a channel-level setting — it controls how long the slew takes. Which steps actually slew is set per-step while armed: hold Glide while an armed CV channel is active and turn encoders to enable or disable glide flags on individual steps.


Channel Edit

Entry: From the main mode or while armed — press and release Shift + Chan. (short tap — release before 1 second). A 1-second hold enters Global Settings instead.

Press a Page button to focus that channel. Encoders edit per-channel settings for the focused channel. To clear a channel, exit to the main mode and use Fine + Play → Clear Mode (see above).

Page buttons show a chaselight for the focused channel's current playing position. While Shift is held, the page buttons switch to a page indicator (currently selected page lights solid) so you can orient yourself before navigating.

Encoder Panel label Parameter Notes
1 Start Output delay 0–20 ms; LED brightness = amount
2 Dir. Direction Forward / Reverse / Ping-Pong / Random — clamped; LED color = direction
3 Length Step length 1–64 steps; first turn peeks (shows current length without changing); second turn within 900 ms edits
4 Phase Phase rotate Destructive; rotates active steps only
5 Range Voltage span (CV only) 2 / 5 / 10 / 15V — LED: orange / yellow / green / blue; inactive for Gate/Trigger
6 BPM/Clock Div Per-channel clock division First turn peeks (shows current division without changing); second turn within 900 ms edits; LED shows division position on encoder LEDs
7 Transpose Floor voltage (CV only) ±1V per detent, clamped to keep window within hardware limits; LED: red (negative) ↔ grey (0V) ↔ blue (positive); inactive for Gate/Trigger
8 Random CV deviation amount (CV only) ±1 semitone per detent, ±36 st (±3 oct) max; CW = unipolar; CCW = bipolar; 0 = off; LED: grey (non-oct) / blue (oct) CW; salmon (non-oct) / red (oct) CCW; inactive for Gate/Trigger

Exit: Shift + Chan. (short tap) or Play/Reset — saves and returns.

Phase rotate is destructive with no undo.


Global Settings

Entry: From the main mode — hold Shift + Chan. for 1 second. The hold is a two-button combo: press and hold both Shift and Chan. together; if either is released before 1 second, it fires as a short tap instead (which enters/exits Channel Edit). Any other button press during the hold cancels it.

Exit: Play/Reset — saves and returns.

Encoders

Encoder Panel label Parameter LED
1 Start Play/Stop reset mode Red = on (Stop also resets to step 1), off = off
3 Length Master loop length Off = disabled; orange = active (non-bar value); red = bar-aligned (8 / 16 / 32 / 48 / 64 steps)
6 BPM/Clock Div Internal BPM Color zone pulse (red <50, orange 50–79, yellow 80–99, green 100–119, blue 120–149, teal 150–179, lavender 180+)

Play/Stop Reset Mode

When on (encoder 1 red): pressing Stop resets all channels to step 1 in addition to stopping playback. Useful for performance situations where you always want sequences to restart from the top.

Master Loop Length

Encoder 3 (Length): sets a global loop length in 16th-note steps. When non-zero, all channels reset to step 1 simultaneously after the set number of steps have elapsed — regardless of their individual lengths or directions.

  • 0 (off): channels loop independently at their own lengths (default).
  • 1–64: all channels snap back to step 1 every N steps, counted from the last reset (manual, external jack, or previous loop boundary).

The LED snaps to red at bar-aligned values (8, 16, 32, 48, 64 steps = 1–8 bars at 16th-note resolution) so you can dial in bar-length loops without counting. Any other non-zero value shows orange.

The loop boundary is seamless — the last step of the loop plays its full duration, then all channels fire step 1 together on the next natural clock pulse. A manual Shift + Play reset or an external reset jack pulse restarts the loop counter from zero.


Performance Page

Entry: From the main mode — hold Fine + Glide for 1.5 seconds. Encoder LEDs light to confirm. Releasing before 1.5 s cancels without entering.

Exit: Play/Reset — saves to flash.

The Performance Page puts the Phase Scrub slider in control of an orbit engine that manipulates playback positions across channels.

Controls

Control Function
Slider Orbit center position
Page buttons Toggle per-channel orbit follow (lit = channel follows slider)
Shift (held) Freeze orbit center in beat-repeat mode
Shift + Page button Navigate pages

Settings

Shown immediately on entry. Encoder LEDs reflect current values.

Encoder Panel label Parameter LED
1 Start Quantize orbit center Orange = on, off = off
2 Dir. Performance mode Off = disabled / green = granular / blue = beat-repeat ×8 / cyan = beat-repeat ×4
3 Length Granular width or beat-repeat debounce Dim→bright orange (granular) / dim→bright white (beat-repeat)
4 Phase Orbit direction (granular only) Green / blue / orange / lavender
8 Random Phase Scrub Lock Red = locked, off = unlocked

Page buttons also toggle the per-channel orbit follow mask here.

Phase Scrub Lock

Toggle the slider lock with either:

  • Encoder 8 (Random) while in Performance Page Settings
  • Short Fine + Glide (tap and release before 1.5 s) — works from the main mode or from within the Performance Page

Locked: slider is frozen at its current position; encoder 8 LED is red.

Unlock: entering pickup mode — the orbit center resumes only after the slider physically reaches the locked position, preventing position jumps.

Lock state persists across power cycles.


Saving

Catalyst VoltSeq uses intentional saving — data is only written to flash when you explicitly trigger a save.

To save: hold Glide, then press and hold Chan. Keep both held for ~800 ms. All page buttons fast-blink while the hold is counted, then blink 6 times to confirm the save completed.

Order matters: press Glide first, then Chan. Pressing Chan. first blocks the gesture — the module will show channel type colors instead.

Performance Page settings (orbit, lock state) are saved automatically when you exit the Performance Page via Play/Reset.

All other settings — steps, channel types, lengths, clock divisions, global settings — are saved only via the GLIDE+CHAN gesture. Power-cycling without saving will lose any unsaved changes.


LED Reference

Situation LED
Main mode, unarmed Each encoder: channel's current step color (playhead position)
Main mode, step held for editing Each encoder: that step's color across all channels
Main mode, page buttons Chaselight for most recently focused channel
Main mode, Shift held Page buttons: current page lit solid; focused encoder blinks white
Armed CV Each encoder: step CV color for current page; playing step blinks
Armed Gate Each encoder: step gate state; playing step blinks
Armed Gate + Glide held Each encoder: per-step ratchet count (dim = none, bright green = high)
Armed Trigger Each encoder: step ratchet/repeat state; playing step blinks
Armed (any type) + Shift + Glide held Each encoder: per-step randomness amount (violet→grey→white ramp; off = 0)
CHAN held (no page button) Each encoder: channel type color
Armed CV, Shift held Enc 5 = Range color; Enc 7 = Transpose color; all others dark
Channel Edit — enc 1 Brightness = output delay
Channel Edit — enc 2 Green/Orange/Yellow/Magenta = direction
Channel Edit — enc 5 Range: orange (2V) / yellow (5V) / green (10V) / blue (15V); off for Gate/Trigger
Channel Edit — enc 7 Transpose: dim→bright red (negative), grey (0V), dim→bright blue (positive); off for Gate/Trigger
Channel Edit — enc 8 Deviation: light grey (unipolar non-oct), blue (unipolar octave); salmon (bipolar non-oct), red (bipolar octave); off at 0; off for Gate/Trigger
Channel Edit — page buttons Chaselight for focused channel
Channel Edit, Shift held Page buttons: current page lit solid (not focused channel)
Global Settings — enc 1 Red = play/stop reset on, off = off
Global Settings — enc 3 Off = loop disabled; orange = active (non-bar value); red = bar-aligned (8/16/32/48/64)
Global Settings — enc 6 BPM color zone pulse (red <50, orange 50–79, yellow 80–99, green 100–119, blue 120–149, teal 150–179, lavender 180+)
GLIDE+CHAN save (in progress) All page buttons fast-blink (~12 Hz)
GLIDE+CHAN save (confirmed) All page buttons blink 6 times
Performance Page Each encoder: channel's current output step color
Perf Settings — enc 8 Red = locked; blinks red during pickup

Quick Reference

Combo Action
Play/Reset Toggle play/stop
Shift + Play (short tap) Reset all channels to step 1
Fine + Play (hold ~500 ms) Toggle Clear mode
Shift + Chan. (short tap) Enter/exit Channel Edit
Shift + Chan. (hold 1 s) Enter Global Settings
Chan. + Page N Arm channel N
Chan. + same Page N Disarm channel N
Play/Reset while armed Disarm (playback continues)
Shift + Page N Navigate to page N (works in all modes)
Hold Shift (normal/armed) Page indicator on page buttons; focused encoder blinks
Wiggle encoder (no step held) Focus chaselight on that channel
Hold Page N + turn Encoder M Edit channel M's value at step N
Armed CV + Encoder N Edit step N's CV value
Armed CV + Shift + Enc 5 Adjust channel range
Armed CV + Shift + Enc 7 Adjust channel transpose
Armed (any) + Shift + Glide + Encoder N Set per-step randomness amount for step N (0–100)
Armed Gate + Encoder N Adjust gate length for step N
Armed Gate + Glide held + Encoder N Adjust ratchet count for step N (0 = single, 2–8 = subdivide)
Armed Gate/Trig + tap Page N Toggle step N on/off
Armed Trigger + Encoder N Adjust ratchet/repeat count for step N
Hold Glide + step Page N + Encoder M Adjust Gate channel M ratchet at step N (unarmed)
Clear mode + Page N Clear steps + flags for channel N
Clear mode + Shift + Page N Full factory reset for channel N
Channel Edit + Shift + Page N Navigate to page N
Hold Glide + Encoder N Glide time / gate offset / pulse width for channel N
Hold Shift + Glide + Encoder N Offset all ratchet counts for Trigger channel N
Armed CV + Hold Glide + Encoder N Enable (CW) / disable (CCW) glide on step N
Fine + Glide (hold 1.5 s) Enter Performance Page
Short Fine + Glide (tap + release) Toggle Phase Scrub Lock
Glide + Chan. (hold ~800 ms) Save to flash (Glide must be pressed first)
Shift + Tap + Chan. (hold 1 s) Switch to Catalyst VoltSeq mode
Fine + Play + Glide (hold 1 s) Switch to Sequencer mode