phase — synth studio for mac

A whole studio in one window.

An arrangement timeline, a piano roll, a synth editor and effect chains, all in one window. Every track has its own synth, effects and MIDI output, so a track can play the built-in engine, a hardware synth, or both. Native Swift, about 2 MB, starts instantly.

Phase showing four tracks on the arrangement timeline and a drum pattern in the piano roll

The arrangement and piano roll, with the demo song that opens on first launch.

Seven engines, one voice.

Every engine feeds the same voice section: a multimode filter with drive, amp and mod envelopes, two tempo-synced LFOs, a six-slot mod matrix, and poly, mono or legato with glide. Learn it once and you know all seven. 32 presets to start from.

id	engine	method	use
E1	analog	Band-limited saw, square and triangle with sub, noise and 7-voice unison.	bass, lead
E2	wavetable	Six morphing band-limited tables, scanned by envelope or LFO.	pad, motion
E3	fm	Four operators, eight algorithms, per-operator envelopes and feedback.	keys, bell, bass
E4	additive	Sixteen partials with tilt, even/odd balance and inharmonic stretch.	organ, glass
E5	pluck	Karplus-Strong strings with damping and pick position.	guitar, harp
E6	modal	Struck resonators modelled as bar, bell, glass, membrane, string or tube.	mallet, perc
E7	drums	A synthesized kit on the General MIDI map, with tunable kick, snare, hats and toms.	beats

Effects

Chain them on any track or the master bus. A safety limiter guards the output.

drivebitcrushchorusphaserdelayreverbeqcompressorautofilter

MIDI in and out

Send each track to its own device and channel, sample-timed and latency-compensated. Phase also appears as “Phase Virtual Out” for your DAW. A MIDI keyboard plays the selected track.

Computer keyboard

No MIDI keyboard? The computer keyboard plays any track, as in the panel above. Export the song to 24-bit WAV.

The synth editor with encoders grouped into kick, snare, hats, filter and envelope sections — The synth editor. Blue shapes the source, green the filter, orange the envelopes.

Made for agents to play.

Phase runs an MCP server on your Mac. Connect Claude or any MCP client and it can do everything you can: build tracks, design sounds, write chords and drum patterns, add effects, mix and export. It can't hear, so analyze_mix reports levels, clipping and frequency balance. Every change shows up in the app, and every change can be undone.

connect / claude code

$ claude mcp add --transport http phase \
    http://127.0.0.1:7341/mcp

# claude desktop and other stdio clients
{ "mcpServers": { "phase": {
  "command": "/Applications/Phase.app/
              Contents/MacOS/phase-mcp"
} } }

example session

› slow lo-fi beat in D minor, warm
  rhodes, sub bass, dusty drums

set_song         bpm 78, D minor
add_track        keys, fm, “Rhodes”
add_chords       Dm9 Gm7 Bbmaj7 A7b9
add_drum_pattern x...x.x. swing .18
add_effect       bitcrush, reverb
analyze_mix      peak −1.2 dB, lows +3
update_track     bass −2 dB

songnew_project set_song transport history save_project open_project

tracksadd_track update_track remove_track duplicate_track unmute_all set_synth

notesadd_clip add_notes add_chords add_drum_pattern transform_notes play_notes

effectsadd_effect update_effect remove_effect

midilist_midi_devices set_midi_output

listenanalyze_mix export_audio get_project describe_synth list_presets

Get phase.

Free. One universal app for Apple silicon and Intel Macs running macOS 15 or later. No account, and nothing leaves your Mac: the agent server only listens on your own computer.

.dmg Phase 1.0.0Disk image Download 2.5 MB .zip Phase 1.0.0Zipped app Download 2.2 MB

sha-256: SHA256SUMS

Open the disk image and drag Phase to Applications.
Phase isn't notarized by Apple yet, so macOS blocks the first launch. Open System Settings → Privacy & Security, scroll down and click Open Anyway.
Or run once in Terminal: xattr -dr com.apple.quarantine /Applications/Phase.app
Phase opens with a demo song. Press space to play.