MIDIRack Get MIDIRack
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AUv3 + Standalone · Built for iPad

MIDIRack

The ultimate MIDI toolkit.

Every keyboard from KB-1, a full suite of sequencers, knobs, faders, buttons and XY pads — arranged however you choose, sending MIDI anywhere. Unlock the visual MIDI graph editor and go deep. Wire the controls you touch to the patch you build.

Download on the App Store How it works

Launch price $7.99 $14.99 · graph unlock $7.99 $14.99

  • The KB-1 keyboard suite, reborn
  • Drum, melody, chord, analog, CC + Matrix sequencers
  • 60+ graph nodes · 16 ch + MPE
MIDIRack performance surface with piano, chord pads, MPE keyboards and drum pads.

Factory patch · the surface, playing

Signal path · surface → graph

Build the surface.
Wire up the graph.

Graph · what's underneath The MIDI graph: signal chains wired from MIDI In through processors to MIDI Out.
Surface · what you touch A performance surface with piano, chord pads, MPE keyboards and drum pads.

Control surface

Base app · $7.99 at launch

The KB-1 keyboards, the sequencer suite, knobs, faders and XY pads on a snapping grid — a custom MIDI controller on its own.

Explore the surface

MIDI graph

One-time unlock · $7.99 at launch

A visual canvas underneath: wire MIDI In → processors → Out through 60+ nodes and built-in instruments.

Explore the graph

Better together: every keyboard is a routable node, and every knob binds to a graph parameter — and moves when another node drives it.

01 · Play · the KB-1 suite, reborn

Every KB-1 keyboard lives on.

Piano, chord pads, scale keyboard, the MPE Seaboard and Strings, and drum pads — the whole KB-1 Expressive Keyboard Suite, rebuilt as building blocks. Each one is its own routable node: use them alone or combined, process them in the node graph and create a whole new instrument.

The piano keyboard control: two octaves of velocity-sensitive keys.
Keyboard NOTES · LATCH · ±OCT Velocity-sensitive piano with latch and octave shift.
The chord pads control: one pad per scale degree, each playing a full chord.
Chord Pads DIATONIC · 3–4 VOICES Pads locked to your key — one-finger progressions.
The scale keyboard control: evenly spaced bars locked to the current scale.
Scale Keyboard SCALE-LOCKED Scale-locked bars — wrong notes are impossible.
The MPE Seaboard control: a continuous ribbon keyboard with glide, slide and velocity toggles.
Seaboard MPE · GLIDE · SLIDE MPE ribbon with per-note pitch bend and vibrato.
The MPE strings grid control: rows of pads tuned in fourths.
Strings Grid MPE · 4THS Linnstrument-style isomorphic grid with per-note slide and pressure.
The drum pads control: a four-by-four grid of GM drum pads.
Drum Pads GM · CH 10 4×4 GM drum-pad grid on its own channel.

On its own: send notes and CC straight to external synths, apps or hardware.
In the graph: arpeggiate, quantize, echo or split each keyboard to any of 16 channels or MPE.

02 · Sequence · tap-to-edit, on the surface

A full suite of sequencers.

Not just keyboards: drum, melody, chord and CC step lanes plus analog style and matrix sequencers, edited right on the surface — with a moving playhead, microtiming, per step probability, trigger conditions and more. Drive them from host transport, a Clock node or external trigger pulses.

A 16-step drum sequencer lane with a moving playhead.
Drum Seq 16 STEPS · PER-PITCH One pitch per lane — branch several for a full kit.
A melody step sequencer lane with per-step pitches.
Step Seq MONO · 0 = REST Monophonic melodies, one pitch per step.
A chord sequencer lane stepping through diatonic chords.
Chord Seq I–VII · 0 = REST One scale degree per step, voiced as triads or 7ths.
The analog sequencer lane: eight pitch knobs above a root, with accent and slide layers.
Analog Seq 8 KNOBS · RE-ROOTS A knob per step, walked forward, backward, pendulum or random — play a note and the line re-roots live, SH-101 style.
A CC automation sequencer lane drawing a filter sweep.
CC Seq ANY CC Automation lanes — filter sweeps, rhythmic tremolo.
The Matrix note grid: a four-by-four grid of pitches with a traversal playhead.
Matrix 4×4 → 8×8 · XY TRIG A note grid, not a lane — walk it in Rows, Columns, Snake, Diagonal, Spiral or Random order, or trigger cells from XY inputs.

These aren't toy step grids.

Per-step depth

Velocity, probability, tie and Elektron-style trigger conditions on every step — with microtiming to nudge it off the grid.

Pattern chaining

Four banks per lane. Set a chain and it cycles A→B→C→D, one bank per loop — a full arrangement with no extra wiring.

Scenes

A 4-pad launcher flips every lane's pattern bank at once, each lane crossing over on its own downbeat for a tight switch.

03 · Arrange · the builder

Same blocks. Your instrument.

Keyboards and sequencers aren't a fixed layout — they're building blocks you arrange on a snapping grid. Every shot below uses the same five blocks: chord pads, piano, drum pads, two faders. Three different instruments.

The Stage Rig patch: chord pads and a 4×4 drum kit in the top row, a piano keyboard and cutoff and volume faders below.
Stage Rig Chords and kit up top, a piano below — everything in reach at once.
The Piano First patch: a full-width two-octave piano on top, with chord pads, a drum kit and two faders in a row beneath it.
Piano First The piano takes the full width; chords, kit and faders tuck underneath.
The One Hand patch: seven tall chord pads dominating the surface, with cutoff and volume faders at the right and a slim piano and drum kit along the bottom.
One Hand Chord pads big enough to play blind, faders beside your thumb.

Auto-layout keeps the surface tidy as you add blocks — and the welcome tour has you adding and binding your first control in about a minute.

04 · Wire · the graph unlock · $7.99 at launch

Underneath: a patchable MIDI engine.

A one-time unlock reveals the node graph under the surface. Wire MIDI In → processors → MIDI Out, insert it as an AUv3 in your host, follow host transport, route across 16 channels and MPE.

Visual graph editor

Wire MIDI like a modular rig

Drag nodes onto the canvas and connect them left to right. Splice a processor straight onto a wire, expand a node's ports, tweak parameters inline. Activity LEDs show MIDI flowing through every node in real time.

  • Orange wires carry MIDI, amber edges carry modulation
  • Branch and merge to build complex signal paths
  • Per-node bypass, color tags and group frames
MIDIRack graph editor: MIDI In wired through Life, Quantize, Chord and Echo to MIDI Out, with the Life node's inspector open.

Surface ↔ graph bindings

Your surface, wired

This is where the builder pays off: every keyboard you play is already a routable node, and every knob you placed can bind to any parameter in the patch. Modulate a parameter with an LFO and watch the knob physically move.

  • Route the piano through an arp, chord pads to channel 2
  • Bind knobs, faders and XY pads to any node parameter
  • Live scopes on the surface visualize the running patch
A performance surface with a live Lorenz scope, a grid of knobs for arp and echo parameters, and Cutoff and Volume faders.

Built-in instruments

Hear it instantly

Drop an instrument node into the graph and route MIDI in. The Synth is a real subtractive voice — wave, resonant filter, amp and filter ADSRs; the Drums are a procedural GM kit; the Sampler and Slicer play and chop your own samples. No external synth required.

  • Poly synth: wave, cutoff, resonance, two ADSR envelopes
  • MPE glide, slide and pressure — the synth responds to all of it
  • Or route MIDI Out to any synth in your host
The graph editor with a Step Seq driving a Synth node and a Drum Seq driving a Drums node, the Synth's parameters open in the inspector.

Emergence generators

Patterns that live

Conway's Game of Life, Wolfram rules, a Turing machine, Markov chains, bouncing balls and a Lorenz attractor — generators that evolve instead of loop. Quantize them to your key and they compose with you.

  • Six emergence nodes, all clock-synced
  • Factory patches to start from: Conway Choir, Turing Bass, Starfield…
  • Run them free before you buy — factory patches play without the unlock
The Conway Choir factory patch: a Game of Life node driving quantized voices, with its colony grid visible on the surface.

05 · The node library · hover a chip to see it expanded

61 nodes, ready to wire.

From MIDI utilities and generative sequencers to built-in instruments — every node card below is rendered straight from the app. Expand any node in the editor and each orange ring is a parameter a surface knob or an LFO can drive.

Sequence

9

Control

4

Filter & Route

9

Notes

10

Pitch & Scale

3

Generate & Modulate

15

Emergence

6

Instruments

4

Utility

1
The Turing node fully expanded: In, Trig and Clock inputs, Out and EOC outputs, and modulatable parameters from Rate to Gate.
One node, expanded — every ◦ ring is a parameter your control surface can drive and other nodes can modulate.

Reference · the parts bin

Every block on the shelf.

For completeness: all 23 blocks you can place on a surface, rendered straight from the app. Long-press any block's edge for its settings; auto-layout keeps the grid tidy as you add more.

Play

6

The six KB-1 keyboards — every one a routable node.

  • The Keyboard control, rendered in the app.
    Keyboard Velocity-sensitive piano with latch and octave shift.
  • The Chord Pads control, rendered in the app.
    Chord Pads One-finger diatonic progressions, locked to your key.
  • The Scale Keyboard control, rendered in the app.
    Scale Keyboard Scale-locked bars — wrong notes are impossible.
  • The Seaboard control, rendered in the app.
    Seaboard MPE MPE ribbon with glide, slide and pressure.
  • The Strings Grid control, rendered in the app.
    Strings Grid MPE Isomorphic grid in 4ths with per-note expression.
  • The Drum Pads control, rendered in the app.
    Drum Pads CH 10 4×4 GM kit on its own channel.

Control

5

Bind each one to a graph parameter — or a raw MIDI CC.

  • The Knob control, rendered in the app.
    Knob CC / PARAM Sweep a node parameter or any CC.
  • The Fader control, rendered in the app.
    Fader CC / PARAM Long-throw level for mixes and filter rides.
  • The XY Pad control, rendered in the app.
    XY Pad 2 × CC Two CCs under one finger.
  • The Button control, rendered in the app.
    Button Toggle or momentary — sends on and off values.
  • The Selector control, rendered in the app.
    Selector Pick waveforms, scales and modes with a stepped switch.

Sequence

6

Sequencer lanes and pattern tools, editable mid-performance.

  • The Steps control, rendered in the app.
    Steps 16 STEPS A sequencer lane's pattern, pad by pad.
  • The Step Mods control, rendered in the app.
    Step Mods Per-step probability, ties and conditions.
  • The Lane+ control, rendered in the app.
    Lane+ The whole lane in one card — pattern and mod layers.
  • The Matrix control, rendered in the app.
    Matrix 4×4 16 knobs editing a Matrix seq's cells, playhead live.
  • The Scenes control, rendered in the app.
    Scenes A–D A–D pads that flip every lane to that pattern bank.
  • The Looper control, rendered in the app.
    Looper Record, play and clear a Looper node's phrase.

Watch

6

Live visualizers, fed straight from the graph.

  • The Monitor control, rendered in the app.
    Monitor Live log of every MIDI event flowing through.
  • The Note Scope control, rendered in the app.
    Note Scope Scrolling piano-roll of the notes an arp or seq is playing.
  • The CC Scope control, rendered in the app.
    CC Scope Oscilloscope for CC curves, one color per CC.
  • The Scope control, rendered in the app.
    Scope Markov trails, bounce physics, attractor orbits — live.
  • The Life Grid control, rendered in the app.
    Life Grid 16×12 Draw a Game of Life seed, watch the colony run.
  • The Register control, rendered in the app.
    Register A Turing machine's note register and playhead.

06 · Get it · one-time purchases, no subscription

Two purchases. Yours forever.

The base app is the full performance surface. The graph editor is a single optional unlock. That's the whole price list — no subscriptions, no hidden costs.

Base app Launch price

$7.99 $14.99

  • The six KB-1 keyboards, incl. MPE
  • Drum, melody, chord, CC + Matrix sequencers
  • Knobs, faders, XY pads, buttons, scopes
  • Built-in synth & drums · AUv3 + standalone
  • CoreMIDI out + always-on virtual port

Graph Editor unlock Launch price

+ $7.99 $14.99

  • The full visual graph editor
  • 60+ nodes incl. generators & emergence
  • Surface → graph parameter bindings
  • Save your own graph patches
  • Factory patches run free — try before you buy
Download on the App Store

Launch pricing for a limited window — about $16 all-in with the unlock, vs ~$30 after. Both return to $14.99 each when the window closes.

Desk duty · iPad → your DAW

The MPE controller already on your desk.

Dedicated MPE hardware runs from the low hundreds to well past a thousand. MIDIRack is $7.99 at launch on the iPad you already own — two genuinely expressive MPE surfaces with per-note pitch bend, slide and pressure, playing straight into Logic, Live, Bitwig, Cubase or any CoreMIDI destination.

iPad · MIDIRack Out USB (IDAM) or Bluetooth MIDI your DAW

  • One cable. Plug into a Mac, enable the iPad in Audio MIDI Setup, done — MIDIRack shows up as a MIDI source. No helper app, no driver. Or go wireless over Bluetooth MIDI.
  • Unlike hardware, the layout isn't welded shut. A Seaboard is a Seaboard forever. MIDIRack is whatever the track needs — MPE ribbon for the lead pass, drum pads for the beat, chord pads to sketch the progression, faders on CC for the mix move. Rearranged in seconds, saved per project.
  • Not just keyboards. The step lanes, chains and scenes clock to your DAW and drive its tracks — a hands-on pattern box beside the timeline.
The MPE Seaboard control: a continuous ribbon keyboard with glide, slide and velocity.
MPE · GLIDE · SLIDE Seaboard ribbon
The MPE Strings control: an isomorphic grid in fourths with per-note slide and pressure.
MPE · GRID IN 4THS Strings grid

FAQ

Good to know

What do I get in the base app, and what costs extra?

The base app ($14.99) is the full performance surface — six touch keyboards, knobs, faders, step grids and MPE — plus the built-in synth, drums and MIDI routing. The visual MIDI graph is a one-time in-app unlock ($14.99). It's a single purchase, not a subscription. You can open and run the factory graph patches before you unlock; editing, adding nodes and saving graph patches need the unlock.

I own KB-1 — what does this mean for me?

MIDIRack is a new instrument, not an update to KB-1. Every KB-1 keyboard lives on inside it — piano, chord pads, scale keyboard, the MPE Seaboard and Strings, and drum pads — rebuilt as building blocks you can mix, resize and arrange on one surface, next to a full sequencer suite. KB-1 keeps working as it always has. And MIDIRack launches at $7.99 (with the graph unlock at $7.99) for a limited window before both go to $14.99, so moving over early costs less.

Can I use MIDIRack just for the keyboards and controls?

Yes. The performance surface is the base app and a full control-surface and keyboard builder on its own — six touch keyboards, knobs, faders, step grids and more. Send MIDI and CC to external synths, apps or hardware without ever unlocking the graph. It's the successor to the KB-1 Expressive Keyboard Suite.

Can I use just the graph?

Yes, once you unlock it. The visual MIDI graph then works as a standalone processor or AUv3 insert — wire MIDI In → processors → MIDI Out in your host with little or no custom UI. Tempo-synced nodes follow host transport; the MIDI Out node routes 16 channels and MPE.

Is MIDIRack a synth?

MIDIRack is primarily a MIDI processor — it receives, transforms and generates MIDI rather than making sound on its own. That said, the standalone app includes a built-in polyphonic synth and drum kit so you can hear your patches right away.

Does the standalone make sound?

Yes. The built-in synth and GM-style drum kit respond to your graph immediately (CC 7 sets volume, CC 74 the filter). You can also route MIDI out to your own synths and apps over CoreMIDI and the always-on virtual port.

Which hosts does the AUv3 work in?

MIDIRack runs as an AUv3 MIDI-processor plugin in hosts like AUM, Logic Pro, GarageBand, Cubasis, Drambo and Loopy Pro — anywhere that supports MIDI-effect AUv3s.

Do I need to know how to code?

No. Build by hand — lay out a performance surface and touch keyboards, patch a MIDI graph, or both. There's no scripting required.

Does it support MPE?

Yes. The MIDI Out node exposes all 16 channels plus an MPE connector, and there are MPE keyboards (a Seaboard-style ribbon and a Linnstrument-style grid) with per-note pitch bend, slide and pressure.

What do I need to run it?

An iPad on iPadOS 18 or later. iPhone and Mac (Apple silicon) versions come later — the same app and AUv3.

Want the full picture? Read the MIDIRack manual.

Touch the surface.
Wire the graph.

Start with an instrument you can play in seconds. Go as deep as a patchable MIDI engine when you're ready.

Download on the App Store Read the manual