MIDISketch · Complete Control Reference

Overview & Concepts

MIDISketch is a piano roll plugin that lets you draw MIDI notes with per-note pitch curves, expression automation, and MPE output. It can host VST3/AU synths directly inside it, or route MIDI OUT to synths in your DAW.

Two Output Modes

• MPE Mode: Each note plays on its own MIDI channel. Every note bends independently. Works with Serum 2, Vital, Phase Plant, Pigments, Surge XT, Diva, and other MPE synths.
• Pitch Wheel Mode (Mono Bend): All notes play on channel 1 with standard pitch wheel messages. The pitch wheel follows the newest active note with smooth sub-block interpolation. Configurable bend range (±2, ±12, ±24, ±48 semitones). Works with every synth (Kontakt, Omnisphere, Massive, Sylenth1, etc.). Best for monophonic leads. A green "MONO BEND" indicator appears in the header when active.

Switch modes from FILE → MIDI Settings.

Two Ways to Connect a Synth

• Host inside MIDISketch: Click the Synth tab to load any VST3 or AU synth directly inside the plugin.
• MIDI OUT to DAW: Enable MIDI Output in FILE → MIDI Settings to route MIDISketch's output to a synth on another track.

What is MPE?

MPE (MIDI Polyphonic Expression) assigns each note to its own MIDI channel, enabling per-note pitch bend, pressure (aftertouch), and slide (CC74). MIDISketch uses ±48 semitones as the default pitch bend range. Most synths default to ±2 and must be reconfigured.

Header Bar

The header runs across the top of the plugin.

Extras Dropdown (Grid Settings)

The wrench/grid button in the playback bar opens a dropdown menu with quick-access settings.

Tools

Tools are selected via the toolbar icons or keyboard shortcuts. All shortcuts are rebindable via the Help overlay (? key → Edit Mode).

Piano Roll · Navigation

Scrolling & Zooming

Zoom Range

• Horizontal: 1x to 64x zoom
• Vertical: 0.5x to 8x zoom

Trackpad Scroll Speed

Configurable in Preferences (1.0x to 5.0x) with non-linear acceleration for smooth trackpad panning.

Piano Roll · Drawing Notes

Active tool: Pencil (V)

Note Snapping

Notes snap to the active grid resolution. Grid adapts to zoom level, and you can toggle between Quad (4/8/16/32) and Triplet subdivisions in the playback bar.

Piano Roll · Pitch Curves

Each note contains pitch points that define its pitch bend curve. Points are connected by lines with optional bezier handles for smooth curves.

Adding Pitch Points

Moving Pitch Points (Pencil / Point Tool)

Bezier Handles

Deleting Points

Point Tool Multi-Select

With the Point Tool (P):

Piano Roll · Expression Lanes

A resizable expression panel sits below the note grid. It shows per-note automation curves for MPE expression data.

Drawing Expression

Non-Destructive LFOs

Each expression lane supports non-destructive LFO modulation:

• L = Apply LFO to selected notes (quick-apply with last settings, or opens dialog)
• Ctrl/Cmd + L = Open LFO dialog with full controls
• Waveshape presets: Sine, Triangle, Saw, Square, Random, and drawable custom shapes
• Depth and speed envelope canvases with bezier curves
• LFO metadata is saved/loaded with .ms and .mpe files

CC Automation Lanes

Arbitrary MIDI CC lanes can be added below the expression panel. Each lane targets a specific CC number and MIDI channel. CC data can be recorded live from controllers when REC is armed.

Piano Roll · Selection & Editing

Select Tool (Box Select), E / H

Moving & Transforming Selected Notes

Editing Dialogs (selection required)

All editing dialogs display "Quick Apply: [key]  Settings: Ctrl+[key]" next to the title. These hints update dynamically when shortcuts are rebound.

Flip & Transform

Time Selection

Playback

MIDISketch supports local playback (independent of DAW) and DAW-synced playback.

Metronome

Built-in click track with bar/beat distinction. Toggle via the metronome button in the playback bar.

MIDI Recording

Live Recording Visualization

Notes appear and grow in real-time during recording. Both standard MIDI and MPE recording show:

• Semi-transparent note bodies that extend as recording progresses
• Pulsing red recording border with a bright growing edge
• Live pitch curves, pressure, and slide expression drawn from a lock-free audio→UI snapshot
• ~23Hz visual refresh rate for smooth feedback

MPE Expression Fidelity

When recording with MPE controllers (Seaboard, ERAE Touch, Osmose, etc.), MIDISketch captures high-fidelity expression data:

• Input throttle optimized for dense curve capture (~4x more samples than standard)
• Douglas-Peucker simplification preserves curve detail while keeping file sizes reasonable
• Per-parameter record arm: independently enable/disable capture of Velocity, Pressure, Slide, and Pan

MIDI Triggers

Up to 8 cue points with MIDI Learn. Trigger playback from a keyboard or controller.

• ANY KEY mode / All Octaves mode
• Loop While Held option
• Auto/Trigger toggle in the playback bar
• Diamond markers on the ruler

Loop Marker

The loop end marker (flag in the header) defines sequence length.

Keyboard Shortcuts · Full Reference

All single-key shortcuts are rebindable via the Help overlay (? → click "Edit Keys").

Tools (single key, no modifier)

Editing (single key)

View (single key)

Shortcut Customization

All single-key shortcuts are fully rebindable:

1. Press ? to open the Help overlay
2. Click "Edit Keys" to enter rebinding mode
3. Click any action, then press the new key
4. Conflicts are detected and warned automatically
5. Settings persist in settings.json across sessions

Modifier keys (Ctrl/Cmd, Alt, Shift) for actions like HighlightSelect and AddPitchPoints can be reassigned in the "Modifiers" tab.

Modifier Shortcuts

Stamp Tool Shortcuts

Perform Tool Shortcuts

Right-Click Menus

Multi-Note Context Menu

Right-click after selecting 2+ notes:

Single Note Context Menu

Right-click on a note in Pencil tool: same options as above for one note.

Pitch Point Context Menu (Point Tool)

Right-click on points: point manipulation options including copy/paste pitch.

FILE Menu

Click FILE in the header:

Ghost Notes

Ghost notes are visually dimmed and play silently, useful for structural reference.

Ghost notes are included in MIDI export but output 0 velocity.

Arpeggiator

Accessed via right-click → Arpeggiate on selected notes.

• Pattern: Up, Down, Up-Down, Random
• Rate: Step speed in beats
• Gate: Note length as fraction of step
• Octave range: How many octaves to span

Scale Lock & Key Detection

Scale Lock

Constrain note placement and pitch points to in-scale pitches. When active:

• New notes snap to scale rows
• Pitch point dragging snaps to scale degrees
• Ctrl/Cmd bypasses scale lock for microtonal adjustments

Live Chord & Key Analysis

• Status bar shows the current detected chord in real-time (MPE pitch-curve-aware, 24 chord patterns)
• Rolling key prediction shows top 3 most likely keys with confidence percentages
• Configurable analysis window (1–32 bars)
• Enharmonic deduplication merges equivalent keys (e.g. B major / Gb major)

Spectral Analyzer (SCAN)

FILE → Import Audio... loads an audio file and displays a spectrogram heatmap overlay on the piano roll, useful for transcribing melodies.

Right-Click Context Menu

Right-click on the scan panel header for additional options:

• Hide/Show Settings: Collapses the panel to a 30px header-only bar (heatmap remains visible behind notes)
• Lock/Unlock: When locked, all left-clicks pass through to the piano roll canvas for note placement and editing. An amber "LOCKED" badge appears in the header. Right-click still accessible for unlocking.

Magnetic Trace Mode (Pencil & Brush)

When a spectrogram is loaded, the Pencil and Brush tools gain magnetic trace behavior:

• Left-click + drag over the spectrogram overlay snaps note creation to the strongest spectral ridge
• Pencil trace commits the single strongest snapped note segment
• Brush trace commits all traced segments for continuous painting along frequency ridges
• A glowing, animated preview curve renders in real-time during the trace stroke
• Trace mode activates automatically when dragging over areas with spectral data

FILE → Clear Scan removes the spectrogram.

Image Overlay

FILE → Import Image... loads a PNG or JPG as a semi-transparent overlay on the piano roll. Useful for tracing patterns from screenshots or notation. Includes opacity, position, scale, and lock/free aspect ratio controls.

FILE → Clear Image removes it.

Design / Themes

FILE → Design... opens the theme selector.

14 presets: Default, Midnight, Obsidian, Deep Ocean, Ember, Slate, Sakura, Monochrome, Green Screen, Aero, Crimson, Bubblegum, Arctic, and Custom (fully user-editable with 5 color slots).

Light themes (Monochrome, Aero) automatically adapt all UI elements including text, borders, and button states.

UI Scale

100% / 125% / 150% UI scale toggle pills appear at the top of the Design modal (also available in the Quick Start help overlay footer). All UI elements, fonts, hit-test areas, and layouts scale proportionally.

Hex Color Input

The color picker includes a hex text field (#RRGGBB) below the HSB strips. Click to edit, type hex values, Ctrl+V to paste from clipboard, Enter to apply. An eyedropper button next to the field copies the current color hex to clipboard.

Playhead Customization

• Playhead Color: full color picker for the playhead line
• Playhead Opacity: 0-100% transparency
• Playhead Size: 0-100% thickness scale (affects the playhead line, glow, top triangle, and start marker)

Synth Tab (Hosted Plugin)

Click Synth in the header to open the hosted plugin view.

Loading a Synth

Click the New Synth button (red, top-right of the synth panel). Browse and load any VST3 synth (or AU on macOS).

Synth Hosting Reliability

MIDISketch includes several safeguards for stable plugin hosting:

• Thread-safe graph access prevents crashes when loading/unloading synths during playback
• Warmup grace period (~2 seconds of silence after plugin load) prevents initial audio glitches
• SEH crash protection (Windows) catches access violations from misbehaving plugins without crashing the host
• Multi-bus support: plugins with auxiliary outputs (Omnisphere, Kontakt) have all channels folded into stereo automatically

Built-In Engines

MIDISketch includes two built-in instruments:

• SYNTHSketch: MPE-native wavetable synthesizer with 4 waveforms (Sine, Saw, Square, Triangle), unison up to 7 voices, full ADSR, stereo filter with 4 modes, per-note ±48st pitch bend.
• Built-In Sampler: Load any WAV file as an MPE instrument. Drag-and-drop, auto pitch detection, root note override, trim/loop markers, Hermite interpolation.

Keyboard Layout Support

The QWERTY-to-MIDI keyboard supports three layouts, configurable in Preferences:

• QWERTY (default): standard English layout
• AZERTY: French layout
• QWERTZ: German layout

MPE Setup for Third-Party Synths

MIDISketch's synth browser includes a compatibility database of 170+ synths with per-synth setup guides and MPE tier badges (Verified, Compatible, Basic MIDI, Unknown). See the compatibility list.

MIDISketch Link

MIDISketch Link enables real-time collaboration between multiple MIDISketch instances running in the same DAW session.

Ghost Notes

See notes from other open MIDISketch instances rendered as tinted ghost overlays in real-time. Each instance gets a distinct color (indigo, pink, teal, orange, violet, cyan, lime, amber). Per-instance eye toggles show/hide linked instances.

Cross-Instance Hotswap

From the Link panel, you can clone another instance's synth or MIDI data:

Export (DRAG) Button

The Export button in the header lets you drag your sequence directly into your DAW's piano roll as a standard MIDI file.

MPE pitch curves, slides, and pressure are baked down into standard MIDI pitch bend and CC messages so the exported file works in any DAW's piano roll. No MPE support required on the receiving end.

FOLLOW Button

Controls how the view tracks during playback.

Keyboard shortcut: F toggles between modes.

Audio Export

FILE → Export Audio (.wav), available when a synth is loaded.

1. Renders the sequence through the loaded synth offline (faster than real-time)
2. Writes a 24-bit WAV at 44.1kHz
3. Adds a 2-second tail for reverb/delay decay
4. Shows a result dialog with Save As... to choose final location
5. All file dialogs remember their last-visited directory

Licensing

MIDISketch has a 7-day free trial (no credit card required), after which a license key is required.

• Trial banner shows days remaining at the top
• Activate button opens the license dialog
• License is a one-time $40 purchase covering all future updates
• License verification uses Ed25519 asymmetric signatures. Your license is verified offline, no internet required after activation.
• Legacy licenses from earlier versions are automatically upgraded in the background

MPE & Pitch Bend Setup

MIDISketch defaults to ±48 semitones pitch bend range. If your pitch curves sound like tiny bends, your synth's range is wrong.

MPE Mode

• Each note plays on its own MIDI channel (channels 2–16)
• Pitch bend, pressure, and slide sent per-channel
• Synth must be in MPE mode with pitch bend range set to 48

Pitch Wheel Mode (Mono Bend)

• All notes play on channel 1 with pitch wheel messages
• Pitch wheel follows the newest active note with smooth sub-block interpolation (no zipper noise)
• Configurable bend range: ±2, ±12, ±24, ±48 semitones (must match synth setting)
• RPN 0 (pitch bend range) automatically sent at playback start
• MIDI drag export writes pitch wheel events (not MPE channel splits)
• Green "MONO BEND" indicator in header when active
• Works with any synth, no MPE configuration needed
• Best for monophonic lines and lead bends

How to Switch

Open FILE → MIDI Settings. Select MPE (Polyphonic) or Pitch Wheel under Output Mode. Both MIDI Output and Internal Audio can be active simultaneously.

MIDI OUT Routing by DAW

When using MIDI Output to route to an external synth in your DAW:

Step-by-step setup for your DAW lives in the DAW guides.

File Formats

Keyboard MIDI (QWERTY)

Play notes using your computer keyboard with a 4-row chromatic layout:

• Z–M = bottom row (lower octave)
• A–L = second row
• Q–P = third row (upper octave)
• - / = = shift octave down/up
• Polyphonic with per-note MPE channels
• Works with recording (REC armed)

Toggle via the keyboard icon in the playback bar.

Keyboard Layout

Configurable in Preferences for international keyboards:

• QWERTY (default): English
• AZERTY: French
• QWERTZ: German

Preferences

Accessible from FILE → Preferences:

• Right-click behavior: Context menu or quick erase
• Trackpad scroll speed: 1.0x to 5.0x with non-linear acceleration
• DAW spacebar forwarding: Let Space control DAW transport instead of local playback
• Playhead opacity: Adjust playhead line visibility
• Keyboard layout: QWERTY / AZERTY / QWERTZ for the built-in MIDI keyboard
• File browser memory: All file dialogs remember their last-visited directory

Oscilloscope

Press O to toggle a real-time waveform visualization overlay.

Features:

• Shows audio output waveform in real-time
• MIDI-synced pitch tracking for stable waveform display
• Useful for verifying synth output and checking pitch accuracy
• Left and right channel visualization
• Follow mode tracks the current playing pitch

Camera & Content Creation

Follow / Reveal Mode

• W toggles Reveal mode: notes appear as the playhead reaches them (great for content creation)
• Camera shake and smoothing sliders for cinematic playback

Reference Image Overlay

Import PNG/JPG as background behind the piano roll with opacity, position, scale, and aspect ratio controls. Useful for tracing notation or screenshots.