Fractal Track — manual

A section-sampled CV/gate looper. Capture one or two source tracks, then reshape the loop with composable branches and ornaments.

Introduction

The Fractal track does not generate notes of its own — it watches one or two other tracks (or routing channels), summarizes what they emit over each loop section into a compact buffer (the trunk), and replays that captured loop. On top of the trunk you stack two composable layers: branches (chained transforms of the trunk that play after it) and ornaments (scale-snapped flourish notes injected inside a section). You record once, then reshape forever without re-touching the source.

Everything here is grounded in the firmware as built — defaults, ranges, enum members, key bindings, and step-grid maps come from the model, engine, and UI code.

Prerequisites

• Familiarity with the xformer track/sequence/edit page model (Page+S2 / Page+S1 / Page+S0).
• Understanding of CV/gate concepts in modular synthesis.
• At least one other track running that the Fractal track can listen to, or a routing channel worth sampling.

Part 1 · Overview

A Fractal track has no sequence data of its own in the usual sense. Instead it:

1. Listens to source A and/or source B — another track's emitted gate+CV, or a single routing channel.
2. Observes over each section: every tick while armed it accumulates how long the source gate was high and where in the section it first fired, then commits one summarized cell into the trunk buffer.
3. Replays the captured loop through a loop window, optionally re-ordered, transposed, and ornamented.

The three layers stack:

• Trunk the literal captured loop. Pitch + proportional gate length per cell.
• Branches chained transforms concatenated after the trunk, so the playhead walks trunk → branch 1 → branch 2 → … building a longer phrase from one recording.
• Ornaments probabilistic flourish notes snapped to the scale and injected inside eligible sections.

It is a sampler/looper, not a stochastic or algorithmic note source. Everything it plays traces back to what it captured.

Part 2 · Sources & Capture

Source A and Source B

Each source slot (SrcA, SrcB) selects one of three kinds:

• None — slot empty.
• Track — a parent track. Gate and CV taken natively from that track's output.
• Channel — a single routing channel. The ordered list after the tracks: CvIn1-4, CvOut1-8, BusCv1-4, GateOut1-8, Mod1-8. A channel derives a gate (a GateOut bit, or any channel reading non-zero) and a CV (raw volts, 1V/oct; Mod 0..127 maps to ±5V).

The two-source mix

With both slots set, the parents combine through two independent logic stages.

With only one slot set, that slot passes through alone (no mix). The classic "A=CV, B=Gate" tailoring is just CV=A + GATE=B.

Record-muted (ghost source)

Rec Muted taps the parent's pre-mute intended gate. With it on, the Fractal track keeps capturing a source even while that source is muted — a silent rehearsal you record from without hearing the parent.

Capture cadence and fidelity

Gate length is always proportional: gate-high ticks over total section ticks become a 4-bit gate length (0 = rest, 15 = tie). Feel additionally stores the onset nibble — when in the section the gate first fired — so playback reproduces the original feel.

Record arm, Replace vs Latch, R.Skip

• Record (recordTrigger, per sequence) is the arm. Capture runs only when armed, the track is not locked, and a source is set. Routable.
• Rec Mode — Replace (default) overwrites every section; Latch only writes sections that gated, so silent sections keep prior content (overdub).
• R.Skip (recordSkip, 0-15) packs capture: skips that many sections between writes, and written cells pack consecutively (R.Skip 1 writes half as many cells over the same span).

Capture writes into the record zone (recF..recL); the record cursor wraps within it.

Part 3 · The Trunk & Zones

The trunk buffer holds up to bufferLength cells (default 16, max 128). Three brackets carve it up and must nest:

recordFirst ≤ loopFirst ≤ ornFirst ≤ ornLast ≤ loopLast ≤ recordLast

• Record zone (rec) — outermost. Where capture writes.
• Loop zone (loop) — the window that actually replays.
• Ornament zone (orn) — innermost. Cells inside it are eligible for ornament flourishes.

Moving an outer edge pushes the inner edges it would cross; moving an inner edge clamps against its outer neighbour. The invariant is always enforced.

The tape

The Trunk page draws the buffer as a horizontal tape. Each captured cell is a filled bar: height = pitch (±5 octaves mapped into the tape), width = gate length (0..15 of the cell width). Cells inside the loop window are brighter; the sounding cell is brightest. A vertical playhead marks the read position. Above the tape, three thin lines show the rec / loop / orn zones stacked top-to-bottom, the focused bracket drawn bright.

Part 4 · Branches

A branch is one chained transform of the trunk, derived deterministically from a seed. branchCount (0-7) branches play one after another, concatenated after the trunk, so the global walk is trunk → B1 → B2 → … Each branch reads the previous segment and applies its transform on read; the trunk buffer is never mutated.

Count, Path, Pool, Seed

• CNT (branchCount, 0-7, routable) — how many branches play.
• PATH (path, 0-255 bit-word, routable) — read order. Each path bit flips a branch between outward (walked ascending after the trunk) and held (walked descending after the outward ones). The Branch page prints the resolved order as T>B1>B2…
• POOL (branchPool, 8-bit mask) — which of the 8 transforms the seed may draw from. Empty pool falls back to all-Transpose.
• SEED (branchSeed) — the deterministic draw. Same seed + pool + loop length always yields the same chain. F4 (SEED) reseeds to a fresh random value.

Jumping segments live

On the Branch page the top step row queues a beat-synced jump to a segment: it applies at the next section boundary. The playing block shows a bright border; a queued target shows a Q.

Part 5 · Ornaments

Ornaments inject short, scale-snapped flourish notes inside a section. They are probabilistic and live — rolled per eligible cell from a free-running PRNG. The trunk stays raw; ornament notes snap to the sequence scale on the way out.

Rate and Intensity

• RATE (ornamentRate, 0-100%, routable) — probability an eligible cell fires an ornament at all. 0 = never.
• INT (ornamentIntensity, 0-100%, routable) — which tiers are in the draw pool:
  • 0-39%: the 7 2-step ornaments only.
  • ≥40%: add the 7 4-step ornaments.
  • ≥75%: add Trill.

The Ornament page labels the slider with a tier readout (off / 2-step / 4-step / 8-trill); the underlying eligibility uses the thresholds above.

Lock

LOCK freezes the ornament roll. While locked, every firing repeats the last-fired ornament and its realized shape (direction + lookahead) instead of re-adapting per cell. Capture is also blocked while locked. Toggle it with F4 (LOCK) on the Ornament page, or Shift+F1 on any hero page.

Queued punch-in

The Ornament page step row queues a forced ornament: it ignores rate, zone, and lock, and fires on the next gated cell. A queued ornament reads Q <name>, the last fired reads Last <name>. Consecutive ornament notes leave a one-tick retrigger gap so each note re-articulates.

Part 6 · Playback

Order mode

Forward/Reverse/Pendulum/Random map to the shared sequence run-mode state; Converge/Diverge/Page advance linearly and remap the read index.

Quantize

Quantize is a playback-only snap: Raw (default) plays the captured pitch literally; On snaps the main note to the sequence scale. Trunk storage stays raw either way. Ornament flourishes always snap to their own scale regardless.

Track delay

Delay (trackDelay, 0-16 sections) shifts the resolved main note that many sections later through a fixed ring — a canon/echo against the source. Only the note is delayed; ornaments are re-rolled fresh when the delayed entry surfaces.

Part 7 · The Hero Pages

Page+S0 opens the hero ring: one page object cycling Trunk → Branch → Ornament → Source via F5 (NEXT). Shift+F1 toggles Lock on any of them. The context menu offers INIT (clear sequence params), CLEAR BUF (erase the recorded loop), COPY, PASTE.

Holding Page + S9-S16 opens a quick-edit overlay for, in order: Rec First, Rec Last, Loop First, Loop Last, Orn First, Orn Last, Orn Rate, Orn Intensity. Page + any other step exits.

Trunk page

F1 REC / F2 LOOP / F3 ORN focus that bracket for the encoder; F4 R.Skip focuses R.Skip. The encoder nudges the focused edge by ±1 (Shift = the bracket's last edge). Step keypad — top row S1-8 adds, bottom row S9-16 subtracts:

All edge moves are nesting-clamped. On the Divisor column top = faster (lower divisor value). LEDs: top row dim green (+), bottom row dim red (−).

Branch page

F1 CNT / F2 PATH / F4 SEED focus for the encoder (SEED also reseeds on press). F3 POOL selects the pool layer; an encoder click toggles the focused pool bit. Steps: top row S1..S(N+1) queues a beat-synced jump to that segment; bottom row S9..S16 toggles the 8 transform-pool bits.

LEDs: top row — present segment dim green, playing bright amber, queued bright red. Bottom row — pool bit set = bright green.

Ornament page

F1 RATE / F2 INT / F3 SCALE focus for the encoder; F4 LOCK toggles Lock. Steps S1-S15 queue a forced ornament (id 0-14), ignoring rate and zone. S16 is inert.

LEDs: S1-S15 — slot dim green, last-fired dim red, queued bright amber.

Source page

F1 SrcA / F2 SrcB focus the slot; F3 GATE / F4 CV focus the logic row. Steps: top row S1-S6 selects the gate-logic mode; bottom row S9-S15 selects the cv-logic mode; S16 randomizes both logics.

LEDs: selected mode bright green, other modes in the row dim green; S16 bright amber.

Part 8 · Setup & Routing

Track-scope list (Page+S2)

Track-wide params, hosted by the generic Track page:

• Buffer Length (1-128, default 16)
• Octave (-10..+10)
• Transpose (-100..+100)
• Slide Time (0-100%)
• CV Update Mode (Gate / Always / Last)
• Quantize (Raw / On)
• Delay (0-16 sections)
• Lock (yes/no)
• Rec Muted (yes/no)

Sequence-scope list (Page+S1)

Per-pattern params: Loop First, Loop Last, Order Mode, Divisor, Clock Mult, Reset Measure, Rec First, Rec Last, Rec Mode, Rec Skip, Record (arm), Orn First, Orn Last, Orn Rate, Orn Intens, Capture (cadence), Fidelity, Scale, Root Note, Scale Rotate.

What is routable

Only these Fractal params are routing targets — all per-sequence:

• branchCount
• path
• ornamentRate
• ornamentIntensity
• recordTrigger (record arm)

(Scale and Root Note also route through the shared scale targets.) No track-scope Fractal param is routable.

The four live controls

The hero-page step grids give four hands-on, beat-synced performance controls without leaving the edit page:

1. Branch jump — queue a playback jump to any segment (Branch top row).
2. Pool toggles — flip transforms in/out of the branch draw (Branch bottom row).
3. Ornament punch-in — force any ornament on the next gated cell (Ornament S1-S15).
4. Logic randomize — roll both gate and cv logic at once (Source S16).