Library & files
Two USB sticks
Bringing two identical prepared USB sticks is the standard club precaution. Sticks fail, get left in players and get taken by mistake, and the second one turns any of those from a disaster into a pause.
In practice
Two identical sticks, both tested in a real player, one never in the same pocket as the other.
Prepare both from the same export so they are genuinely identical, then test each in a media player rather than trusting the computer — a stick can mount perfectly on a laptop and be unreadable to a CDJ. Format them the way the players expect, label them so a handover cannot take yours, and keep one on your person rather than in the bag. If a venue is far from home, a third in the bag costs almost nothing.
2
Identical, always
In a player
Where to test them
Separate
Where to keep the second
Where these come from: Standard club practice for USB preparation and redundancy — not catalog figures. For what we can measure, see how to prepare one properly.
Why it matters
It is the cheapest insurance in DJing and the most commonly skipped. A stick that will not mount in an unfamiliar player is not rare — filesystem quirks, firmware differences, a connector that has been kicked a thousand times — and a set that exists in one place is a set that can end in the first thirty seconds.
The second failure it covers is human. Sticks are small, black, and identical to every other DJ’s, and handovers happen in the dark while someone is talking to you. Losing one at the end of a night is routine; losing the only one is not.
Frequently asked
Do I really need a second USB stick?+
Yes. Sticks fail in unfamiliar players, get taken during handovers and get left behind, and the second one turns each of those from the end of your set into a thirty-second pause.
How should I format a DJ USB stick?+
In the format the players expect rather than whatever your computer defaults to, and check the result in an actual player. A stick that mounts on a laptop can still be invisible to a CDJ.
Should the two sticks be identical?+
Yes — exported from the same library at the same time. A backup with a different library on it is a different set, which is not what you want to discover mid-changeover.
Related terms
USB prep
USB prep is exporting the tracks, grids, cue points and playlists you need onto a drive a club player can read. What is not exported does not exist once you are behind the decks.
Export mode
Export mode is the state in which DJ software acts as a preparation tool — organising, analysing and writing to a device — rather than playing anything. Performance mode is the other state, where the same software plays.
Device library
A device library is the database written onto a USB stick alongside the audio, holding the playlists, cues, grids and search index the player reads. It is a separate export from your computer’s own library.
Backup
Backing up a DJ library means copying two separate things: the audio files, and the database holding the cues, grids, playlists and history. Losing either one loses years of work, and they live in different places.
Explore: Rekordbox USB checker · USB prep · Handover · All DJ terms