MIDIRack
the ultimate MIDI toolkit
8,99 € · In-App Purchases
Launch offer - get the base app and graph unlock for just $7.99 each ($14.99 each regular)
MIDIRack is a MIDI toolkit for iPad. Build a custom touch surface from the KB-1 keyboard suite, an all-new sequencer suite, knobs, faders, buttons and more — then unlock a visual MIDI processing graph (one time in-app purchase) and wire it into anything, from a simple custom controller to a full-on groovebox or a self-playing generative composer. Play it on its own and send MIDI anywhere, as an AUv3 plugin in your favourite host or a standalone instrument.
THE BASE APP — PERFORMANCE SURFACE
Design a custom control surface on a snapping grid:
• The KB-1 keyboard suite — piano, diatonic chord pads, scale-locked keyboard, MPE Seaboard ribbon, MPE Strings grid (4ths), and a 4×4 GM drum-pad grid. Each is its own routable node with latch and octave shift. Successor to the KB-1 Expressive Keyboard Suite.
• A suite of sequencers — drum, melody, chord, analog and CC step grids and a Matrix note grid, with a moving playhead, swing and microtiming. Per-step velocity, probability, tie and trigger conditions; pattern chaining and 4-pad scene switching for full arrangements; a knob-per-step analog machine that re-roots live as you play.
• Knobs, faders, XY pads, buttons and live visualizers — bind to raw MIDI CC or graph parameters.
On its own: a rich custom control surface builder — send MIDI and CC to any synth, app or hardware, no graph required.
WITH YOUR DESKTOP DAW
Expressive MPE hardware costs hundreds. MIDIRack turns the iPad you already own into a controller for Logic, Live, Bitwig, Cubase or any desktop DAW:
• Two MPE surfaces — the Seaboard ribbon and the Strings grid send per-note pitch bend, slide and pressure to any MPE-capable instrument on your desk. • A controller that changes per track — MPE ribbon for the lead, drum pads for the beat, chord pads for the progression, faders mapped to CC for a mix move. Rearrange in seconds; save a surface per project. • Sequence it too — clock the step lanes to your DAW and drive its tracks. • Easy to connect — one USB cable to a Mac via IDAM (Inter-Device Audio and MIDI), or wirelessly over Bluetooth MIDI. No driver, no helper app.
UNLOCK — MIDI GRAPH (in-app purchase)
Wire MIDI In → processors → MIDI Out on a visual canvas:
• 60+ node kinds — arpeggiators, scale/key quantizers, transposers, chords, echoes, swing, humanize, euclidean rhythms, random/generative melodies, LFOs, CC tools, an analog knob-per-step sequencer, a Matrix sequencer and a Counter. • Built-in instruments — Synth, Drums, a Sampler and a loop Slicer make sound right in the graph; no external synth required. • Emergence generators — Conway's Game of Life, Turing machine, Wolfram rules, Markov, bouncing balls, Lorenz attractor — for evolving, living patterns. • Presets — factory patches grouped by category (control surfaces, generators, keyboards, utilities): Amen Engine, Starfield, Conway Choir, Turing Bass, Cellular Drums… Save your own.
ROUTING & MPE
• MIDI Out exposes all 16 channels plus an MPE connector — multitimbral, multi-instrument setups. The built-in synth responds to MPE. • Every keyboard is its own node — process and route each one independently.
PLAYS OUT OF THE BOX
• Built-in polyphonic synth, drum kit, sampler & slicer or send MIDI to your gear via CoreMIDI and an always-on virtual port.
Ratings & Reviews
- This app has not received enough ratings or reviews to display an overview.
Now on iPhone. The app and the AUv3 plug-in run on iPhone in landscape, with a folding menubar, a full-screen lane editor, and a surface thats optimized for the small screen.
New
- Presets sync with iCloud and appear in Files as named .midirackpatch files. Organise them in folders, import and export them.
- Multi-page control surfaces with named pages and page-select buttons.
- Strings grid in any key: pick a root and scale, and glide stays pitch-true.
- Custom drum pad layouts: set every pad's note and label, or learn from your kit.
- Bluetooth MIDI pairing in MIDI Ports.
- Dockable inspector you can float or hide. Inspectors and the surface scroll by scrollbar so sliders never pan the view (switch back in Settings).
- Play from your computer keyboard: QWERTY piano, Z/X octave, C/V velocity, 1–8 and Q–I for drum pads.
- XY mode on the Seaboard and Strings surfaces: left-right sends pressure, up-down sends slide, independently.
- Apple Pencil expression: force plays the keys and pads, and drives pressure separately from slide on the MPE surfaces. Custom response curves per keyboard, with a live preview pad.
- CC pickers list standard controller names.
Fixed
- AUv3 failing to load in some hosts on iOS 18.
- AUv3 fits small host windows: compact chrome, a minimum size, and a scrolling surface.
- Keyboards and sequencer UI at one row high.
- Release bounce when dragging surface controls, and keys triggering through sheets.
The developer, Kai Aras, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Size
- 29.7 MB
- Category
- Music
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - iPad
Requires iPadOS 17.0 or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Graph Editor Unlock 8,99 €
- Provider
Kai Aras
- Kai Aras has identified itself as a trader for this app and confirmed that this product or service complies with European Union law.
- Address
Kai Aras
Postfach 131105
70069 Stuttgart
Germany - Phone Number
+49 15154624829 - Email
kai.aras@numericalaudio.com
- Copyright
- © Kai Aras
