Geert Bevin has released version 2.0 of Uwyn MIDI Tape Recorder, the MPE-aware MIDI recorder he first gave away as an open-source Christmas gift back in 2021. The update is free for existing users and adds a standalone application, a continuous loop record mode, and proper session documents. More interesting than the feature list, though, is the argument the app has always made: that the way most DAWs record MIDI is not the way expressive controllers actually play.
A Tape Recorder, Not a Sequencer
The concept behind MIDI Tape Recorder is deliberately narrow. It records MIDI the way a tape machine records audio — as a continuous stream, in the order and at the timing it arrived. There is no quantisation, no note editing, no CC lane surgery. Four independent tracks, record enable, input monitoring, overdub, punch in and out, undo and redo, and that is broadly it.
Bevin's rationale, stated on the product page, is that most modern DAWs still reorder and delay MIDI messages to accommodate their editing features, and that those changes alter how the messages influence the sound. For a straightforward note-and-velocity part, this is usually inaudible. For MPE it is a different story.
Why MPE Raises the Stakes
An MPE performance is not a sparse event stream. Every held note carries its own channel, and on that channel a continuous flow of pitch bend, channel pressure and CC74 timbre data describes what your finger is doing millisecond by millisecond. A four-note chord played on an Osmose, a Continuum or a LinnStrument can generate several thousand messages in a couple of seconds.
Two things can go wrong when that stream is written to a track. The first is thinning — expression data being decimated to keep the timeline manageable. The second, and subtler, problem is reordering: if a note-on arrives after the pitch bend that was meant to precede it, the synth applies the bend to the wrong note, or applies it a fraction too late. On a percussive patch you may not notice. On a bowed or breath-style patch, where the attack shape carries the phrasing, it is the difference between a performance and an approximation.
This is exactly the point one commenter made on the Synth Anatomy report of the release: players who work with Haken-engine hardware tend to be the first to notice what a round trip through a DAW costs them. Whether every DAW suffers equally is a fair question — Bitwig, Ableton and Logic have all improved their MPE handling considerably — but the gap is real enough that a tool built purely around capture fidelity still has an audience.
What Version 2.0 Adds
The standalone build is the headline. Previously an AUv3 plugin, MIDI Tape Recorder now runs on its own on macOS and iOS with the full feature set: record, overdub, playback, and CoreMIDI input and output routing to other apps and hardware. Recording continues with the screen locked, which turns an iPhone into a pocket capture device for an MPE controller.
Continuous loop record is the other significant addition. As an opt-in mode, the loop keeps rolling and re-records over your take on each pass rather than stopping at the end — a much more tape-like way of chasing a take than repeatedly hitting record.
Version 2.0 also introduces sessions and documents: your work autosaves, and you can save, open and share .mtrec session files. On the robustness side, MIDI file import has been hardened so that malformed files can no longer cause out-of-bounds reads or event desync, and importing an empty track now correctly clears the destination track. Several other fixes round out the release.
The original feature set remains, including detection of the MPE Configuration Message per track, MIDI file import and export, start and stop locators, snap-to-beat, AUv3 parameters for all controls, and four virtual MIDI cables where the host supports them.
Where It Fits in a Rig
The obvious workflow is to treat it as a scratchpad in front of your DAW. Play a passage, capture it losslessly, export the MIDI file, and import that into your session — with the original as a reference if something sounds wrong after editing. For iPad players it doubles as a self-contained looper for AUv3 MPE instruments.
It is worth being clear about what it is not. There is no editing, no CC recording in the traditional sense, and no arrangement view. That is the design, not an omission.
MIDI Tape Recorder 2.0 is out now, priced at $9.99 on the App Store, free for existing owners, and runs as a standalone app and AUv3 plugin on iOS and macOS. The code remains open source.