The DJ: a live mix of your own music

In Signal, the DJ plays a continuous mix from your music on this server: songs that fit go one into the next on the beat, in keys that sit well together, following the mood you choose. Start it from a music library, a playlist, an artist, an album, a genre, a song or all your music.

• Only your own music. The DJ mixes songs from Jellyfin's music libraries and audio playlists, as the person who started it may open them, so Jellyfin's library access and parental limits apply. It never mixes audiobooks, podcasts, radio or streaming services.
• Vibe and curve. Chill, steady or party sets the tempo and energy; the curve keeps it flat, lets it build, peak in the middle or wind down. From the phone: skip, more or less like this song, hold this song longer, ask for a song, and the effects pad (filter, echo, brake, cut bass, riser, scratch, spinback, loop roll, flanger, phaser, reverb, gater, bitcrush, wobble, beat repeat, delay throw, rewind, and one-shots: stinger, air horn, siren, laser, impact and downlifter). Every effect keeps to the beat and never clips. Every command is answered at once; you hear an effect within two or three seconds.
• How songs change. The DJ picks each change by how the two songs fit: long blends, filter sweeps, reverb washes, echoes, drops, double drops, beat rolls into a drop, backspins, tape stops, power-downs, noise risers, reversed-cymbal swells and more. Choose a style: auto, smooth (nothing abrupt), club (drops and build-ups), radio (short and tight) or creative (the unusual ones).
• Your genres and your queue. Keep a mix to some genres, or blend them in the shares you choose. The person playing the mix can add songs, albums or playlists to play next or later, move or remove what's coming up, and lock a song so the DJ keeps it where it is. A song that doesn't mix with the one before comes in with a quick cut, and the phone says so.
• The DJ's words. Song names and the DJ's words show as captions on the TV. If the voice pack is installed, one of two DJs talks: DJ Signal (laid back, for chill mixes) or DJ Reelhost (upbeat, for parties). They react when you skip or ask for more, count in the drops, call out to the crowd and give shout-outs, but never say song names: those stay on screen. How often is chattiness, 0 to 3; how loud is the talk volume.
• Parties. A mix shared with the household can be joined on another TV or phone, or cast to a Chromecast (not sample-for-sample in step). Others can ask for songs (at most three waiting each), send a shout-out of up to 80 characters, shown at the next change and never spoken, and press hype to lift the energy. When several people ask for the same song it becomes one request with votes, and the most asked-for songs come sooner; you can let requests in once two (or more) people ask. Guests invited to Watch Together can do the same on a shared mix. The person who started it can save what played as a Jellyfin playlist in their own account, and anyone can keep songs on their own never-play list.
• Guests pick songs with a QR code. Turn on Let guests pick songs and the TV shows a QR code. Guests scan it with their phone camera and get a small page from this server, with no app and no sign-in: they type a name, search your music, ask for songs, vote, and (if you allow) send shout-outs and hype. They only see song names and covers from your music libraries, never your other libraries, and they can't play anything themselves. Requests from guests can play straight away, wait for you, or wait for votes. The page works on your home Wi-Fi; from outside only if you allow it and Signal works from away. It stops when you turn guests off, when the mix ends, or after 12 hours.

On your computer

Under Connect devices → DJ: Reelhost listens to each song once to find its tempo, beats, key and loudness. It only reads your songs and never changes them; what it finds is kept in Reelhost's own folder. See how many songs are done, Analyse my music now, Pause analysing, or analyse only overnight. Analysis waits while a mix plays, and the songs next in a mix are always done first. Choose who may start the DJ (everyone, grown-ups only, or only admins) and whether requests from others play straight away, wait for the person playing the mix, wait for two people to ask, or are off.

DJ voices are a separate download, so Reelhost's installer stays small: Download (38 MB) installs DJ Signal and DJ Reelhost; there are also packs with only one of them. Reelhost checks every download before installing it, checks there's room on the drive first, and carries on where it stopped if the connection drops. Without the voices, the DJ talks in captions. An optional sound pack adds real recordings (like a crowd cheer) for the one-shots; it only ever contains sounds released as CC0 (public domain).

• One voice pack at a time. Switch to this on another voice pack downloads it and replaces the one installed once the new one checks out; until then the old one keeps working. Update to v2 works the same way.
• Cancel stops a download and deletes what was downloaded.
• If files of an installed pack go missing or get damaged, it says so under the pack, and Re-download installs it again.
• Remove deletes a pack (Reelhost asks first). A mix playing carries on: with the voices gone the DJ talks in captions; with the sounds gone it uses its own made-in sounds.
• Clear DJ analysis forgets every song's tempo and key (when no mix is playing). Reelhost listens to each song again the next time it analyses; your songs aren't touched.
• Removing packs and clearing the analysis are done on the computer, not from a phone. In Signal apps, admins can remove a pack too.

The DJ is part of Reelhost Complete. It needs ffmpeg: on a computer Reelhost uses Jellyfin's own; in Docker, set REELHOST_FFMPEG or let Reelhost download it on the Recordings screen. When you remove Reelhost, the DJ's analyses, downloaded voice and sound packs and never-play lists go with it; your music stays exactly as it was.