Ableton/Live/UG/12 Editing MPE
- Viewing and editing per-note MPE data such as pitch bend, slide and pressure, and how Live's devices, Push 2 and plug-ins use it.
- MPE (MIDI Polyphonic Expression) attaches control data to each note rather than to a whole MIDI channel, so a controller can shape several parameters of every note while it sounds.
- To receive MPE from a controller, turn on MPE Mode for it in Settings → Link, Tempo & MIDI. A track whose input is an MPE controller always listens on All Channels.
- Clip View's Note Expression tab shows five dimensions per note: Pitch (per-note pitch bend), Slide (Y axis), Pressure (poly aftertouch), Velocity and Release Velocity. Any MIDI clip can be edited this way, whether or not it was recorded from an MPE device.
- Controller setup is covered in Ableton/Live/UG/34 MIDI and Key Remote.
- Open a clip in Clip View and choose the Note Expression tab (
Option+3 on Mac, Alt+3 on Windows). - Slide, Pressure, Velocity and Release Velocity each get an expression lane; only Slide and Pressure show by default. Pitch envelopes draw on top of their notes in the MIDI Note Editor.
- Toggle buttons on the left show or hide each lane; the triangle button below them shows or hides all enabled lanes at once.
Option-click (Mac) or Alt-click (Windows) the triangle to show every lane. - Lanes resize individually by their split lines, or together by dragging the line between the lanes and the note editor.
- MIDI track meters light their lowest dot blue when per-note controller changes pass through.
- Click a note while the Note Expression tab is open to bring its Pitch, Slide and Pressure envelopes forward; Velocity and Release Velocity appear as markers. Other notes are greyed out.
Breakpoints and segments
- Click a line segment to add a breakpoint; click a breakpoint to delete it. Values show while creating, hovering or dragging.
- Right-click a breakpoint → Edit Value to type an exact value; right-click a preview breakpoint → Add Value to create one at an exact value.
- Drag a breakpoint or segment to move it. Selected breakpoints move together.
Option-drag (Mac) / Alt-drag (Windows) a segment to curve it; double-click with the same modifier to straighten it.- Hold
Shift while dragging to lock to one axis, or to fine-tune vertically. - Dragging a breakpoint horizontally over its neighbour removes the neighbour.
Grid
- The grid is off by default in this tab and its settings are saved with the clip, separate from the other tabs. Turn it on with Snap to Grid or
Cmd+4 (Mac) / Ctrl+4 (Windows).
Whole-note edits
- Slide, Pressure, Velocity and Release Velocity envelopes can be scaled across the whole note: click outside the note, hover until the envelope turns blue, then drag up or down. Pitch can't be scaled this way.
Cmd+A / Ctrl+A on an envelope selects all its breakpoints so they can be shifted by the same amount.- Moving or stretching a note moves or stretches its expression with it.
- Pitch breakpoints snap to the nearest semitone while holding
Cmd (Mac) / Alt (Windows) with the grid off. - Pitch envelopes hide when Fold is on;
Z zooms to fit the pitch bend in the time selection; Clear All Envelopes in the context menu removes a selected note's expression.
- With Draw Mode on, drag freehand in the Pitch, Slide and Pressure lanes to draw an envelope.
- Toggle Draw Mode with
B, the Control Bar's Draw Mode switch, or the Options menu. Holding B turns it on only while held. Shift while dragging gives finer values. With the grid on, drawing makes steps as wide as the visible grid; hold Cmd (Mac) / Alt (Windows) to draw on the grid while it is off.
- Many of Live's own instruments support MPE and ship with MPE presets. They also respond to polyphonic aftertouch from Push 2; see Ableton/Live/UG/36 Push 2.
- Live can read and modulate MPE data for plug-ins that support it.
- A plug-in's MPE Mode on/off state is saved with its default configuration. Plug-ins with MIDI outputs can send MPE as well.
- The MPE/Multi-channel Settings dialog sets up MPE output for hardware synths with particular zone needs, or for multi-timbral plug-ins that can be played from an MPE controller without official MPE support.
- It opens from the Ext. Instrument device, from a MIDI track's I/O section in the mixer, or from the context menu of an MPE-enabled plug-in.
- Ext. Instrument: pick a target in MIDI To, choose MPE in the second menu, then open that menu again and choose MPE Settings….
- Mixer I/O section: with the target device chosen in the track's MIDI To, choose MPE in the second menu, then reopen it and choose MPE Settings…, in either the Session or Arrangement mixer.
- Plug-ins: right-click the device's title bar.
- The dialog chooses the MPE zone (lower or upper) and how many note channels it uses, or switches to multi-channel mode with any range of note channels.
- Each zone has a global channel for controls that aren't per-note: channel 1 for the lower zone, channel 16 for the upper. The number of note channels sets the zone's polyphony, for example 1–11 for the lower zone and 12–16 for the upper.
- A track outputs to one zone only, so using both zones takes two tracks. Zones apply only to MPE output.
- Two tracks routed to the same MIDI output, one per zone, can drive two MPE synths chained through MIDI thru, or two sounds in one synth.
