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String and Pad Sustain Editor

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String and Pad Sustain Editor

The Sustain Editor is designed for instruments that hold long notes — string ensembles, synth pads, organs, choirs. Instead of placing individual note rectangles in a piano roll, you place chord blocks and shape their dynamics with envelope curves.

When to Use It

  • Writing string or pad parts that hold chords for multiple bars
  • You want to control dynamics (volume swells, fades) visually
  • You think in terms of "a Cm chord that swells in" rather than "three MIDI notes at specific velocities"

Layout

  • Timeline — horizontal, divided into bars and beats
  • Chord blocks — colored rectangles spanning the chord's duration, labeled with the chord name (e.g., "Cm", "F", "G7")
  • Dynamics curve — a line overlaid on each chord block showing volume over time

Placing Chords

Action How
Add a chord Click an empty space on the timeline — a chord picker appears
Change a chord Click an existing block to open the chord picker
Move a chord Drag the block body left/right
Resize a chord Drag the right or left edge
Delete a chord Right-click and select Delete, or select and press Delete

The chord picker shows suggestions from the harmony engine — chords are color-coded green/yellow/red based on how well they follow the previous chord.

Dynamics Envelope

Each chord block has an editable dynamics curve that controls how loud the chord plays over its duration.

Editing the Envelope

  • Control points appear on the curve — drag them up (louder) or down (softer)
  • By default, each block starts with a simple sustain (flat line at medium volume)
  • Double-click the curve to add a new control point
  • Right-click a control point to delete it

Common Shapes

Shape Effect
Flat line Steady, unchanging volume
Ramp up Swell — chord gradually gets louder
Ramp down Fade — chord gradually gets softer
Up then down Swell and fade — the classic pad movement
V shape Dip in the middle — creates a breathing effect

Transitions Between Chords

Right-click the boundary between two chord blocks to set the transition type:

Transition Effect
**Cut** Hard switch — first chord stops, second chord starts immediately
**Crossfade** The two chords overlap briefly, blending together
**Swell** First chord fades out, brief silence, second chord fades in

Voice Leading

When Auto Voice-Lead is enabled (default), each new chord is voiced to minimize the movement between notes. For example, going from C major (C-E-G) to F major, the engine might choose F-A-C voiced as F-A-C rather than jumping to a distant inversion — keeping the notes close together for a smooth transition.

Voicing Styles

Select a voicing style from the toolbar:

Style Description
**Close** All notes within one octave — compact, warm
**Open** Notes spread across two octaves — spacious, orchestral
**Drop 2** Second-highest note dropped an octave — common in jazz arranging

How It Works Internally

Each chord block is stored as a group of simultaneous notes in the standard pattern format. The dynamics envelope modulates note velocity over time during playback. This means:

  • The output is standard MIDI — compatible with any instrument or DAW export
  • You can switch to the piano roll to see/edit the individual notes if needed
  • Humanization still applies on top of the dynamics envelope

Keyboard Shortcuts

Shortcut Action
Click empty Add chord block
Click block Change chord
Drag block Move in time
Drag edge Resize
Delete Remove selected block
Double-click curve Add envelope control point
Right-click point Remove envelope control point
Ctrl+Z Undo
Ctrl+Y Redo
V Cycle voicing style
T Cycle transition type (on block boundary)