DJ Changeovers, B2B and a Booth Emergency Plan.

Previous guides cover technical failures diagnosed with meters and checks. This one is different: the task is keeping the performance going when somebody leaves, two people arrive together or the computer dies, rather than repairing equipment. Its six scenarios—DJ changeover, B2B, computer failure, backup player, emergency phone and what to pack in an emergency bag—share one principle: agree the response beforehand instead of improvising during the event.

In every case, the prerequisite is that music never stops. Every decision during a failure must begin by preserving whatever is already playing.

DJ Changeover: Preparing the Transition

A DJ changeover is a logistical operation, not a creative one. The outgoing DJ needs to know how far their set runs, which track is last, the next DJ’s starting tempo and who operates equipment during the changeover seconds. Agree all of that beforehand, in direct conversation with the equipment in front of you.

The reliable sequence: first, the outgoing DJ chooses a closing track and announces its duration. Second, the incoming DJ prepares the first track at the agreed tempo and leaves it cued on their deck. Third, during the closing track, the outgoing DJ leaves master level in place and steps aside without touching further controls. Fourth, the incoming DJ enters on the first beat and takes the assigned channel.

Two details avoid an awkward moment: agree who controls the mixer during the changeover and prevent both DJs touching controls simultaneously. Preparation of the whole session, with the list checked before and afterwards, appears in the Spanish guide Checklist Before and After a Performance.

B2B: Two DJs, One Booth

B2B—back to back or taking turns—means two DJs sharing a booth during the same set. It is not two sets added together: it is one performance with two brains, requiring explicit agreements.

First, distribute equipment and decks. Pioneer DJ’s guide describes agreeing on equipment, organising tracks and allocating decks. The classic mistake is both DJs loading the same player or both waiting for the other to cue. Write the allocation before starting: who takes decks 1 and 3, who takes 2 and 4, who cues each track and how the handover is signalled.

Second, agree the transition mechanics. DJ TechTools describes several options: full crossfading for longer turns, passing control while maintaining tempo for quick turns, and parallel equipment connections for advance preparation. Any works if both DJs know it; none works when invented on the spot.

Third, work together. Taking turns does not mean debating tempo or the next track live. Make those decisions outside the booth or silently; in the booth, execute the agreement.

Computer Failure: The Exit You Have Prepared

A computer failure mid-set has one priority: keeping the music going. The response is therefore to switch to the source already prepared for this case, rather than restart.

Advance preparation has three parts. First, load the backup player with set material on separate media, not the same stick the computer uses. Second, test the audio path, including turning equipment off and back on, so the change is purely physical: disconnect, connect, raise the fader. Third, leave the computer in a known state before departure: disable updates and background processes, as the optimisation guide reminds you, to reduce the chance of a failure.

During a failure, the rule has two parts: do not restart the computer live, and do not touch controls that still work. Keep what is playing, connect the backup source, then investigate what happened. Diagnose memory, library and peripherals properly while somebody else supplies the music, or at home.

Backup Player: The Reserve Source

A backup player is independent of the computer, whether it is booth equipment or a mixer module with its own media. Its defining requirement is working without anything else: no computer, network or extra configuration.

For it to be useful, prepare it beforehand. Export the material to backup media using the program you normally use, check the tracks open and mark the entry track. Software offline mode is for exactly this: rehearsing and organising tracks without the audio interface, preparing the contingency plan in good time.

Test the entire procedure at least once: disconnect the main source, start the backup player and bring a track to the fader. Passing that test turns computer failure from an emergency into a source change.

Emergency Phone: What It Can and Cannot Do

The phone is the final line, and works if kept in its proper role: covering the gap until the main source returns rather than replacing it. Its advantage is always being available; its limitations are output quality, connection robustness and the risk of a call or notification interrupting audio.

Preparation: load a long track or stable loop without relying on mobile streaming. Lower output volume before connecting the cable to avoid a level surge into an open fader. Test the cable and every adapter: modern phones often need an adapter that is not always in the bag. Assign the channel and check booth monitoring receives it.

During use: flight mode with Wi-Fi disabled, or silent mode, no touching the screen and power connected. A device running out of battery after ten minutes was a distraction, not a plan.

What to Pack in an Emergency Bag

The emergency bag is the physical part of the plan: the minimum kit needed to execute any preceding scenario. It is a short, fixed list checked before every departure, not an infinite spares box.

Minimum contents: a spare stick with the exported set, another empty stick, two balanced audio cables, a spare network cable, a power cable, the input and output adapters you use, a splitter if needed, and tape or markers for labels. Add a charger and battery for the emergency phone, because that plan consumes power too.

What makes the bag useful is closing the list: check it on return, replace used items and confirm nothing remains lent out. A bag with half its contents used at the previous performance is a promise, not an emergency bag.

Next Step

With the contingency plan settled, the booth troubleshooting area is complete. The natural next step is to cross-check these guides against the Spanish guide Checklist Before and After a Performance and Library Backups: The 3-2-1 Rule, establishing the habit that prevents most of these scenarios.