MIDIRack vs P252 MDN Diode
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
MIDIRack
Design custom MIDI control surfaces with a variety of instruments and sequencers. Unlock advanced features like a visual MIDI processing graph for complex routing and generative music creation. Use it standalone, as an AUv3 plugin, or to control desktop DAWs.
- Customizable touch surface design
- KB-1 keyboard suite with MPE support
- Advanced step and matrix sequencers
- Visual MIDI processing graph
- Built-in instruments and samplers
- Connects to desktop DAWs via USB or Bluetooth
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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.
P252 MDN Diode
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P252 MDN Diode is a germanium diode bridge compressor created by Pulsar Modular and Marc Daniel Nelson. Nearly two years in the making, it delivers the weight, movement and harmonic character of the rare germanium diode-bridge design - now on your iPhone and iPad. Use it as an AUv3 plug-in in your favorite host (Logic Pro, GarageBand, AUM, Cubasis and more) or as a standalone app processing live sound from your microphone. KEY FEATURES: - Germanium diode bridge compression with program-dependent behavior - RESPONSE TIME and RELEASE controls tuned for musical timing - Ratios from gentle 2:1 up to Limit, plus Linear mode - FF / FB sidechain topology switch - External sidechain input (AUv3) - STOCK / DRIVE transformer voicings and NORM / HEFT weight modes - AIR switch and 3-way analog noise floor - MATCH gain matching for honest A/B decisions - A/B compare with copy, MOD and oversampling - Simpson-style VU metering (RMS in/out) plus dual gain reduction meters - Touch-friendly "Link Threshold & Trim Out" and "Link Trim In & Out" gain staging - Full preset manager with folders, favorites, import and export - Parameter automation in AUv3 hosts Audio is processed entirely on your device - no account, no data collection, no internet connection required.
Screenshots
Verdict
The clearest difference is in-app purchases: P252 MDN Diode at none against MIDIRack's 1. P252 MDN Diode also leads on iOS requirement (15.0 vs 17.0). MIDIRack's advantage is price ($14.99 vs $19.99). On ads and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
MIDIRack costs $14.99 and P252 MDN Diode $19.99 up front. MIDIRack sells 1 one-off in-app purchase. P252 MDN Diode asks for nothing beyond the download.
| Parameter | MIDIRack | P252 MDN Diode |
|---|---|---|
| Price | $14.99 — better | $19.99 |
| Rating | 4.8 (8 ratings) — better | — |
| Positive reviews | 66.7% of reviews | — |
| Number of ratings | 8 — better | — |
| Update frequency | Every 4 days | — |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | — |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 17.0 | 15.0 — better |
| Further details — not scored | ||
| Size | 28 MB | 29 MB |
| Age rating | 4+ | 4+ |
| Developer | Kai Aras | Pulsar Modular |
In-app purchases
MIDIRack
- Graph Editor Unlock$7.99
P252 MDN Diode
No in-app purchases
Questions
Is MIDIRack free?
Is P252 MDN Diode free?
Do MIDIRack or P252 MDN Diode have ads?
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