One-pass build from a plain music folder into Engine DJ — duplicates collapsed, playlist groups, smart playlists, history sessions populated, paths verified.
You have a music folder — maybe years of downloads, ripped CDs, gifts from friends — and you want it in Engine DJ. The native import in Engine DJ reads files one folder at a time, doesn't deduplicate, doesn't surface quality issues, and certainly doesn't catch fake-320 MP3s or fake FLACs hiding in the source. So you import once, find chaos, and start over.
Supported today
Rekordbox · Serato DJ · VirtualDJ (incl. Favorite Folders) on Windows 10+ and macOS (Apple Silicon + Intel).
Importing a raw folder into Engine DJ normally means trusting whatever the file tags say and praying there are no duplicates or fake-320s. MLD audits the folder first — acoustic fingerprint duplicate detection, FFT-based quality scoring — and then writes Engine DJ m.db with the clean set. Engine DJ expects matching analysis files (.dat) next to each track for performance — pure path writes without analysis miss waveforms and cues. MLD handles that under the hood.
Yes — MLD writes into Engine DJ's native library, so the app has to be installed on the machine. Engine DJ doesn't need to be running during the write; in fact, it should be closed.
Run the Library Health scan before the build. Duplicate Scan groups copies of the same recording (acoustic fingerprint matches across formats and bitrates). Audio Quality Score flags fake-320 MP3s and fake-FLACs with a 0–100 score per file. Both run before the Engine DJ library is created.
MLD maps your folder structure onto playlist groups, smart playlists, history sessions sensibly — top-level folders become playlist folders, nested folders become nested playlists. You can review the plan before any write.
No. All scanning, scoring, and writing happens locally. MLD's local database is SQLCipher-encrypted; audio files never leave the computer.
Yes. Folder Library mode doesn't require uninstalling anything. You can run Engine DJ from the same files Plex/Navidrome/Roon already read.
Free tier covers detection and viewing. Lifetime access is $49 — $19 for the first 100 DJs.
