Zone — keyboard split / zone filter for Ableton Live

One tiny Max for Live MIDI effect per instrument: it plays only the keys you give it, then transposes the result. Two things make it worth it:

• Transpose after the split — the split point never moves with it. The zone is filtered on the notes you actually play; the octave/semitone shift hits only the survivors, downstream. So you can transpose the sound as much as you like and the split boundary stays exactly where you set it — it never transposes itself. Define the split once, shift the sound freely on top.
• Mappable min/max bounds — which Ableton can't do natively. Low and High are real Live parameters, so the split point is MIDI-mappable and automatable (Ableton's built-in key zones are not). Map several Zones' bounds to one CC and move a split across instruments, live.

Stack instances to build splits and layers.

Bonus — light your splits on a WLED strip. Turn on Lights and each Zone paints its keyboard range as a coloured band on an LED strip, live, via the open wled-midi convention — see below.

Get it

1. Download zone.amxd (also listed on maxforlive.com).
2. Drop it on a MIDI track, before the instrument (or into a rack chain).
3. Requires Live with Max for Live (Suite, or Standard + M4L). Built on Live 12 / Max 8.6.

Manual — every field and what it does

The device is a few rows of controls (no on-screen keyboard). Every control is a Live parameter, so it's automatable and MIDI-mappable — including the Low/High split bounds, which Ableton's native key zones don't let you map.

Global

Field	Default	Impact
Bypass	off	On = hard bypass: every note passes through raw — no zone filter, no transpose. Off = normal.
Mute	off	On = blocks all note output (empty zone, nothing plays). Non-note MIDI still passes; held notes get their note-off so nothing hangs.

Limits — the zone

A note plays only if it falls inside the zone. Each side has an on/off toggle, a value, and a Learn button.

Field	Default	Impact
Low	0	The low bound. With Lo on, only notes ≥ Low pass. Its note name is shown beside it (C-2 at 0).
High	127	The high bound. With Hi on, only notes < High pass — the High note itself belongs to the upper zone, so adjacent split zones meet with no overlap. Note name shown (G8 at 127).
Lo on / Hi on	off	Enable each bound. A side that's off is open (no limit). Both off = full range, everything passes.
Learn Lo / Learn Hi	—	Click to arm, then play a note: that note becomes the bound. Editing is the learn.

Defaults 0 / 127 with limits off = a fully-open zone (everything through); the 0/127 values are just neutral starting points for when you switch a limit on.

Post transpose — applied after the filter

Field	Default	Impact
Oct (Octave)	0	Coarse shift, ±4 octaves.
Tone	0	Fine shift, −6…+5 semitones. Tiles exactly with Octave (no gap, no duplicate) — the Roland/Korg half-octave convention. Final pitch = note + Oct×12 + Tone, clamped 0–127.

Transpose via CC — drive Tone and Octave from MIDI CCs

Lets external CCs (a fader, a clip envelope, a script) move the Tone and/or Octave value. Handy when you author the CC by value (e.g. a clip sending CC to this track). Each has its own CC number and enable; the mapping mode is shared.

Field	Default	Impact
Tone on / Oct on	on	Per-target master enable. On = the watched CC drives Tone / Octave and is consumed (never reaches the instrument). Off = that CC passes through untouched.
Tone CC#	102	Which CC number drives Tone, on any channel that reaches the track. 102–119 is the MIDI "Undefined" range → no collision with mod-wheel (1), expression (11), sustain (64), cutoff (74)… (Channel is Ableton's track-input job — no channel field here.)
Oct CC#	103	Which CC number drives Octave (same rules).
Center	64	(shared) Where 0 sits in the CC value. 64 = value 64 → 0 (a window around 64). 0 = value 0 → 0 (wraps, so you reach the negatives even though a CC value never goes below 0).
Range	Step	(shared) Step = 1 CC value = 1 step (a window; the rest saturates or wraps). All = the whole 0–127 sweep is interpolated across the steps.

The four modes (Center × Range) — shown for Tone (folded to −6…+5); Octave works identically with its own ±4 range (9 steps, value 64 + n):

	Step (1 value = 1 semitone)	All (interpolate 0–127)
Center 64	window 58–69 → −6…+5, saturates outside — value 64 + n, no math	ramp: value 0→−6, 64→0, 127→+5
Center 0	wrap /12: 0→0, 1→+1, …, 5→+5, 6→−6, …	value 0→0 … 127→−1 (12 steps, no return to 0)

Default 64 + Step = the window: value 68 → +4, 64 → 0, 58 → −6, 69 → +5, outside saturates.

Why a CC per target, with modes? Octave (9 values) and Tone (12 values) are far coarser than a CC's 127 steps — a straight linear sweep wastes most of the range and lands between values. So each shift gets its own CC, plus a shared choice of how the value maps onto its few slots — in particular the window around 64, where value 64 = 0 and every step is one increment (64 + n = n): trivial to author by hand and precise, instead of hunting for the right point on a 127-step fader.

Drive it from a Stream Deck. The Trevliga Spel Stream Deck MIDI plugin is an absolute gem — it fires MIDI (CC, Program Change, Note…) straight from physical Stream Deck keys. Assign a key to send CC 102 at a fixed value and you get one-press Tone recalls, or drive any of Zone's parameters hands-on. Honestly a killer companion for this device.

Passthrough

Everything that isn't a note passes through untouched — sustain, expression, pitch bend, aftertouch, program change, and any CC except the ones assigned to Tone / Octave (each consumed while its enable is on). Held notes always get their note-off, even if you move a bound, transpose, mute or bypass while they ring: no stuck notes.

Splits & layers

Put one Zone at the head of each instrument and MIDI-map the bounds directly (Ableton's MIDI map, Cmd-M) — no rack, no internal linking. Map several Zones' Low/High to the same CC and one control moves the split across all of them at once:

Stage-keyboard mode	With Zones
Solo (one sound everywhere)	limits off
Split (bass left / keys right)	Zone A High + Zone B Low on one CC = movable split point
Layer (two sounds together)	both full range (or both bypassed)
Split + layer	any mix — stack as many Zones as you like

Light your zones on a WLED strip (OpenLamp)

Zone can show each split on an LED strip — every instrument's keyboard range lit as a coloured band, moving live as you move the split. It drives wled-midi, the open MIDI↔WLED convention, in its zone position mode.

How it works. Turn Lights on and Zone holds two notes — the zone's low and high boundary — on the Lights Ch channel, sent to a MIDI port named OpenLamp. A wled-midi implementation (the engine, the browser tool, the Bome pack…) listening on that port lights the LED band between the lowest and highest held note, in the channel's colour. Move a bound → the band moves. Stack Zones on different channels → each instrument's range shows in its own colour, a live map of your split.

Control	Default	Impact
Lights	off	On = emit this zone's boundaries to the OpenLamp port (the WLED band). Off = nothing sent. Muted/bypassed zones clear their band.
Lights Ch	1	The MIDI channel the band is sent on = which colour in wled-midi's hand/zone map (ch 1 = hand 1, ch 2 = hand 2…). Give each Zone its own channel.

A side with its limit off is open, so the band runs to the strip end (note 0 / 127) on that side — exactly the range that actually plays. High is exclusive (the filter passes note < High), so the band tops out at High − 1, flush with the last sounding key.

Setup (once). Create a virtual MIDI port named OpenLamp (macOS: Audio MIDI Setup → IAC Driver; Windows: loopMIDI) — the same port the wled-midi implementations listen on. Zone's internal [midiout OpenLamp] sends straight to it, independent of Ableton's track routing (your instrument still gets the normal filtered notes). Point your wled-midi implementation at your WLED device, set it to strip / zone mode, and turn Lights on.

The Lights output is additive and non-intrusive — it never touches the note stream going to your instrument. If the OpenLamp port doesn't exist, the midiout is simply silent; nothing else changes.

Try it in the browser

Interactive demo (or open zone-demo.html locally) — move a macro, watch one split point drive several zones.

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Under the hood

File	Purpose
zone.amxd	the device, ready to use — source of truth (hand-arranged layout + logic)
zone.js	the brain — zone filter, octave/tone transpose, Tone-via-CC, note tracking
zone.maxpat	the patcher inside the device (UI + wiring), kept in sync with zone.amxd
gen_zone_maxpat.py	the original scaffold that generated the first patch (reference only — see hacking notes)
rack/	Zone Keyboard rack preset + demo set + docs

midiin → midiparse ┬ notes ──────────────→ [js zone.js] ┬ outlet 0 → midiout            (filtered + shifted notes → instrument)
                   ├ control-change ──────→ [js zone.js] └ outlet 9 → midiout OpenLamp   (zone boundaries → wled-midi `zone`)
                   │                                       (Tone/Octave-via-CC: consumed, or re-emitted untouched)
                   └ everything else → midiformat → midiout                              (untouched passthrough)

zone.js has 10 outlets: 0 = MIDI out (to the instrument), 1–2 = Low/High value feedback, 3–4 = note-name labels, 5–6 = learn-state labels, 7–8 = Tone/Octave value (CC-driven), 9 = WLED lights (the zone's two boundary note-ons → midiout OpenLamp). The lights path is independent of outlet 0, so it never disturbs the notes reaching your instrument.

Hacking notes:

• zone.js is referenced, not frozen in the device, and runs with autowatch = 1: edit the file next to the device and Max hot-reloads it. (Adding/removing a js outlet needs a full device reload, not a hot-reload.)
• The presentation layout is hand-arranged in Max and lives in zone.amxd — it is the source of truth. zone.maxpat is that device's patcher JSON, kept in sync. The .amxd is a 32-byte ampf header + the patcher JSON, so structural changes can be applied to it directly.
• gen_zone_maxpat.py scaffolded the original structure. It does not reproduce the hand-tuned layout or the later additions — re-running it would reset the presentation. Keep it as a reference for how the wiring was first built; don't overwrite the shipped files with it.

Latest version, changelog and issues live here on GitHub — the maxforlive page is a pointer to this repo.

License

MIT — see LICENSE.

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Splits for Live — and an optional bridge to light. Zone is a standalone Max for Live device; its optional WLED output speaks the open wled-midi convention — the agreed dictionary between MIDI (the MIDI Association) and WLED. Part of the OpenLamp ecosystem; free for anyone to build on.