Tool 04 · 88 keys, no window
JustPiano托盘钢琴
A piano that lives in your menu bar.
Five instruments, all synthesised. Plug in a MIDI keyboard and play: no DAW, no window, no setup, no sample library to download. Hit record, play, export a .mid or a .wav.
Opening Logic or MainStage just to noodle for two minutes is absurd. JustPiano starts in a second and is always ready — and it records everything you play in the background, so the improvisation you did not hit record for is not lost.
What it does
- About 6 ms out, 3 ms if you push it
It auto-connects to your keyboard and reconnects by itself when you re-plug it.
- A real piano tone, not a sample pack
88 keys and two velocity layers, synthesised from a physical model: inharmonic partials, hammer strike-position combing, frequency-dependent damping, double-decay envelopes, unison string beating, soundboard radiation, hammer and key-bed noise.
- Five instruments
Three struck-string pianos — Grand, Upright, Felt — and two electrics, Rhodes and Wurlitzer, modelled as what they actually are: a struck steel bar seen through a non-linear pickup.
- Pedals that behave the way the spec says
Sustain, sostenuto and una corda. Only CC121 lifts the pedals, and a held damper keeps notes ringing through CC123 — which is what the MIDI spec actually asks for.
- Export what you played
A Standard MIDI File — type 0, 480 PPQ, pedal and pitch bend included — or a rendered 44.1 kHz 16-bit stereo WAV. There is also a rolling capture of everything since launch.
- Light, and it stays out of the way
No sample library anywhere: an instrument is 32 to 48 MiB of audio your Mac renders itself, once, on first use, then caches. There is a virtual MIDI port for DAWs, on-screen keys you can click, and a global mute hotkey for when the same keyboard is also driving a session.
Get it
macOS 11 or later and Python 3.9 or later. Clone the repo and follow Option A in the README to build the app; it takes a couple of minutes and puts JustPiano.app where you want it.
You build it on your own Mac, so there is nothing to notarise and nothing to trust. Check python3 --version first; if it is missing, run xcode-select --install.