4DJ

4DJ is DJ software with the layout DJs already know: decks, mixer,
effects and browser where you expect them. It goes further with stems
made on your own computer, transitions that stay in key and in tempo,
a tablet as a second screen, and controllers that map themselves.

- 2 or 4 decks with hotcues, loops, beatjump, slip, key lock and SYNC
- StemX: splits any track into drums, bass, other and vocals on your
computer, nothing is sent online
- SmartSync: the next crossfade glides in key and in tempo
- Three-band EQ, filter, two FX units with 19 effects
- Library with playlists, smart playlists, instant search and import of
collections from other DJ apps
- Audio recorder, microphone with talkover, loop recorder, live inputs
and timecode vinyl
- More than 110 MIDI consoles recognised as soon as they are plugged in
- RemoteDeck: a tablet or phone becomes a second screen

BEFORE YOU START (one time only)
After installing, open a terminal and type these two commands, then
open 4DJ again:

 sudo snap connect 4dj-mixer:alsa

 sudo snap connect 4dj-mixer:raw-usb

- alsa: sound cards with separate master and headphone outputs, and
MIDI consoles
- raw-usb: consoles with lights and jog wheels that talk over USB HID

The Snap Store does not connect them for you yet: without them 4DJ
still plays music, but your sound card and console may not show up.

Consoles driven over HID (such as the Kontrol S2 MK3) also need a udev
rule once: when you plug one in, 4DJ shows the command to copy into the
terminal.