Gradus

Features

Circular Ring UI

• Concentric ring display — All 9 lanes arranged radially across concentric rings, with steps visible at a glance instead of scrolling through horizontal strips
• Per-lane colored playhead highlights — Each lane's active step lights up in its own color and races around the ring at that lane's independent speed, visually communicating polymetric relationships as the colors drift in and out of phase
• Direct ring editing — Drag radially on velocity, gate, pitch, and ratchet rings to adjust values; click to cycle chord, inversion, modifier, and condition values
• Euclidean center visualizer — A dot ring in the center of the display shows the active Euclidean rhythm pattern (hits, steps, rotation)
• Detail strip with lane tabs — 9 color-coded tabs (VEL, GATE, PITCH, MOD, COND, RATCH, CHORD, INV, DELAY) alongside the ring display, each opening a linear step editor for precision editing. Contextual controls (swing, jitter, and lane-specific features) appear per tab

Pattern Engine

• 9 independent polymetric lanes — Velocity, Gate, Pitch, Chord, Inversion, Ratchet, Modifier, Condition, and MIDI Delay lanes each with independent step counts (1–32) for evolving, non-repeating patterns
• 12 arpeggiator modes — Up, Down, Up/Down, Down/Up, Converge, Diverge, Random, Walk, As Played, Chord, Gravity, and Markov
• Markov Chain mode (new in 1.6) — Picks the next note by sampling a 7×7 transition probability matrix keyed by scale degree (I/ii/iii/IV/V/vi/vii°). 5 built-in presets (Uniform, Jazz, Minimal, Ambient, Classical) plus a Custom preset that activates when any cell is hand-edited
• Editable Markov matrix (new in 1.6) — Visual 7×7 grid overlaid on the ring display; drag cells vertically like mini sliders to set transition probabilities. Row/column labels show Roman numeral scale degrees. Collapsible to a compact trigger button when not needed
• Per-lane speed multipliers — Each lane can run at its own clock rate (0.25x to 4x), adding a second dimension of polyrhythmic complexity on top of independent lane lengths
• Per-lane speed curves (new in 1.6) — Each lane's speed can vary over one loop cycle via a free-form Bezier curve with adjustable depth (0–100%). 7 shape presets (Flat, Sine, Triangle, Saw Up/Down, Square, Exponential) plus free-form editing: double-click to add points, drag handles for curvature. Creates accelerando/ritardando effects within each cycle
• Per-lane swing (new in 1.5) — 8 independent swing parameters (0–75%), one per lane; skews each lane's advance timing so odd and even steps alternate between long and short. Creates polymetric groove interactions on top of per-lane speeds
• Per-lane length jitter (new in 1.5) — 8 independent jitter parameters (0–4 steps); each lane re-rolls a random length offset when it wraps, extending or shortening its cycle. Creates evolving non-repeating patterns that differ per lane
• MIDI Delay lane (new in 1.7) — 9th lane that generates delayed echo copies of arp notes as real MIDI events. Per-step control over delay time (free or tempo-synced), feedback (0–16 repeats), velocity decay, pitch shift (±24 st per repeat for harmonic cascades), and gate scaling. Multi-knob grid editor with horizontal scrolling and per-step active toggles
• Euclidean rhythm generation — Mathematically distributed rhythmic patterns with configurable hits, steps, and rotation offset
• Conditional triggers — 18 per-step conditions including probability (10%–90%), ratio patterns (1:2, 2:3, 3:4, etc.), first note, and fill/not-fill triggers

Per-Step Details

• Per-step ratcheting — 1–4 sub-divisions per step with a Shuffle selector (Even / Triplet / Dotted) for the subdivision feel
• Ratchet velocity decay (new in 1.5) — Each ratchet subdivision can decay in velocity like a bouncing ball (0–100%), producing a natural falloff instead of flat velocity bursts
• Per-step modifiers — Active, Tie, Slide, and Accent flags per step for expressive articulation control
• Step pinning with pin grid editor (new in 1.5, grid editor in 1.6) — Pin individual steps to a fixed MIDI note regardless of the arp pattern, creating pedal tones, drone notes, and anchor points within moving patterns. Pinned steps bypass pitch offset, transpose, scale quantization, and range mapping. A 32-cell inline pin toggle row above the pitch bars provides click-to-toggle visual editing

Chords & Pitch

• Chord generation — Per-step chord types (None, Dyad, Triad, 7th, 9th) with inversions (Root, 1st, 2nd, 3rd) and voicing modes (Close, Drop 2, Spread, Random)
• Strum mode (new in 1.5) — Spread chord note-on events in time (0–100ms) with configurable direction (Up, Down, Random, Alternate) for a guitar-strum effect
• Scale quantization — 16 scale types with selectable root note; optionally quantize input notes to the selected scale
• Scale-aware transpose (new in 1.5) — Global transpose (±24 steps) that shifts by semitones in chromatic mode and by scale degrees in scale mode, so the result always stays in key
• Note range mapping (new in 1.5) — Constrain output to a MIDI range (floor/ceiling) with Wrap, Clamp, or Skip modes; keeps arpeggios within a playable register
• Velocity curve (new in 1.5) — Apply Linear, Exponential, Logarithmic, or S-Curve shaping to the whole velocity output with a blend amount, reshaping the dynamic feel without redrawing every step

Performance & Playback

• Spice & Dice — Blend in random pattern variations with adjustable amount; re-roll with the Dice button for fresh generative results
• Humanize — Add subtle timing variations for a more natural, less mechanical feel
• Latch modes — Off, Hold, and Add modes for hands-free pattern playback
• Fill mode — Latching toggle for live performance — activates fill-conditional steps for build-ups and transitions
• Built-in audition synth — Simple oscillator (sine/saw/square) with adjustable decay so you can hear patterns without external MIDI routing
• Tempo sync and free rate — Lock to host tempo with 30 note values (1/64T through 4/1D), or run at a free rate from 0.5–50 Hz
• Copy/paste between lanes — Copy step data from any lane and paste into another for quick pattern duplication
• 40 factory presets across 8 categories — Classic, Acid, Euclidean, Polymetric, Generative, Performance, Chords, and Advanced

Integration

• MIDI output — Arpeggiated notes (including MIDI Delay echoes) output as standard MIDI events for driving any instrument in your DAW
• Preset sharing with Ruinae — Arp presets use the same parameter IDs, enabling cross-plugin preset exchange
• Full parameter automation and host preset management
• Cross-platform: VST3 (Windows, macOS, Linux) + Audio Unit (macOS)

Lane Types

• Velocity — Per-step velocity from 0% to 100%, controlling how hard each note is struck
• Gate — Per-step gate length from 0% to 200%, controlling how long each note sounds relative to the step duration
• Pitch — Per-step pitch offset from −24 to +24 semitones, adding melodic contour to the arp pattern
• Chord — Per-step chord type selection (None, Dyad, Triad, 7th, 9th) for harmonic richness
• Inversion — Per-step chord inversion (Root, 1st, 2nd, 3rd) for voice leading control
• Ratchet — Per-step sub-division count (1–4) for rapid note repetitions within a single step
• Modifier — Per-step flags (Active, Tie, Slide, Accent) for detailed articulation
• Condition — Per-step trigger condition (probability, ratio, fill) for generative variation
• MIDI Delay (new in 1.7) — Per-step echo post-processor with 7 parameters per step: active toggle, sync mode, delay time, feedback count, velocity decay, pitch shift, and gate scaling. Generates real MIDI note events, so echoes play through your instrument with full polyphony

Each lane has an independent step count (1–32) and speed multiplier (0.25x–4x). Combining different lengths and speeds across lanes creates complex, evolving polyrhythmic patterns.