Browse your rekordbox libraries, follow two CDJs and keep a record of your sets. OLC runs on a Mac or Raspberry Pi and shares its interface with browsers on the same network. Playback, cueing and mixing stay on your CDJs.
Download OLC · Installation · Using OLC · 0.5.0 release notes
- Follow the mix: live three-band waveforms, track overviews, BPM, pitch, key, master/sync status, exported beats, phrases, cues and loops.
- Find your next track: browse USB libraries and playlists; search, sort, combine metadata and My Tag filters, and save filter presets. Harmonic key highlighting and played-track marks help with selection.
- Preview tracks: listen through the browser or desktop window before loading a player, with artwork, waveforms and seeking.
- Load either deck: send a track to a stopped CDJ from a player-mounted USB or a OneLibrary USB attached to the Mac/Pi. Both decks can use the same local library. Compatible originals remain unchanged; built-in transcoding prepares eligible unsupported audio as WAV or AIFF.
- Record and reuse sets: capture tracklists automatically, edit saved sets, import supported rekordbox histories, browse past sets as playlists, and export text, CSV or PDF.
- Manage CDJ settings: import saved My Settings, edit reusable profiles, push them to stopped CDJ-2000nexus players, and optionally apply profiles on connection.
- Adjust the display: automatic sizing, resolution presets, stacked or extra-wide side-by-side decks, beat-phase/reference-waveform comparisons, configurable filters and track-list sizes.
Screenshots illustrate active sessions; connection and playback states are illustrative.
Use macOS 13+ on Apple Silicon or Intel, or a Raspberry Pi 4/5 with 64-bit Raspberry Pi OS Bookworm or later.
- Install OLC and connect the host and CDJs to the same local network.
- Select the CDJ network connection in MENU. Use physical player numbers 1 and 2; leave number 4 free for OLC when serving a local USB.
- Select a library in BROWSE. Stop the destination player, then press CDJ1 or CDJ2 to load a track. Mac local USB serving requires the included Local USB Support installation.
- Keep OLC running and the music USB attached during playback. For a remote screen, open the network address shown in MENU.
A Pi can start without a monitor or desktop login. Follow the headless setup.
Display and filters · Local USB and transcoding · Set history · CDJ configuration profiles
Fine waveform tracking is limited on a paused non-master player; use the CDJ's own display and audio for precise cueing. One local USB library is served per connection session. Platform/model coverage and other current limits are listed in compatibility.
For contributors: Build and checks · Architecture · Hardware verification.
OLC is GPL-3.0-only and independent of Pioneer DJ, AlphaTheta and rekordbox. See acknowledgments and source credits.