Open DJ 1.0 alpha

This is the first public alpha of Open DJ, a local-first DJ app for macOS. It is for trying Open DJ, not for a gig you cannot afford to lose.

Highlights

• Four decks on one screen. EQ, filter, trim and a crossfader on every deck, running on a Web Audio engine. LESS view keeps it to two decks.
• Bring your rekordbox library. First run reads your tracks, playlists, beatgrids, cues, keys and waveforms. Open DJ never writes to rekordbox, and your library stays on your Mac.
• AutoPlay. Open DJ mixes the next track in for you, beat-matched with Beat Sync. Take over at any point.
• Move several knobs at once. Shift+click dials to select them, then scroll or drag to move them together. Drag up and down for one side and left and right for the other, to bring one track in while taking another out.
• Headphone cue on a single output. With one audio device, split cue puts the master in one ear and your cue in the other.
• See the vocals. A vocal lane shows where the singing sits, and synced lyrics run along the waveform for tracks that have them.
• Record your set. REC captures the master mix to a file.
• Scriptable. Every control has a local HTTP API and an opendj command-line tool, so you can drive the app from your own scripts.

Install

Download OpenDJ-1.0.0-alpha.1-aarch64.dmg below, open it, and drag Open DJ to Applications.

• Apple silicon Macs only, macOS 14 (Sonoma) or newer.
• Signed with an Apple Developer ID and notarized by Apple.
• SHA-256: 83d9bdc59b7eefe18f4fe4ec0b251585484e4e17662a24ed70ce6b36bd4e6480

Known issues

• Stems use a lot of memory. Each track loaded with stems takes about 130 MB for every minute of audio. In a 30-minute AutoPlay test of this build on a 16 GB Mac, memory held steady between tracks at about 2.5 to 3 GB, and dropped to about 1.2 GB once every deck was ejected (about 0.4 GB at launch). Quitting Open DJ releases all of it. On a Mac with 8 GB, avoid loading stems on all four decks. The CHANGELOG in the source still describes the larger growth measured on the previous internal build, which this build fixes.
• AutoPlay can stop between tracks. With Beat Sync Max on, if Beat Sync cannot line the next track up with the playing one, the next track may load but not start, leaving silence. We have seen this when the two tempos are more than about 16% apart, and when the playing track has run past the end of its beat grid. Turn Beat Sync Max off to avoid it. A fix is coming in the next alpha.
• Setup can stay on "Import in progress" after a small import. Rarely, when a folder imports in a second or two, the setup window keeps saying "Import in progress" after the import has finished. Your music is already imported: choose "Use the app while this runs", or quit and reopen Open DJ. A fix is coming in the next alpha.
• The AutoPlay options menu is awkward to use. It closes if you move the pointer slowly from the AutoPlay button down to it, so move in one quick motion onto the option you want. Pressing Space there does not tick a box, so use the mouse. In the Light skin its text is hard to read; the Default and Gothic skins show it clearly. These are being fixed for the next alpha.
• >| (next-track loop) is experimental: the transition is abrupt and does not blend yet.
• Unfinished controls: a control with no real data source behind it is visible but inert, and its tooltip says so. Open DJ never shows invented data.

Reporting problems

There is no public bug tracker for this alpha yet. A contact route will be announced on open-dj.com shortly after release.

Full notes: the CHANGELOG.md entry for app-v1.0.0-alpha.1 in the source.