I’ve been DJing professionally now for more years than I care to remember, and throughout that time I have regularly heard stories of things going wrong for other DJs that have brought the disco to an abrupt stop; sometimes only for a while, but other times causing a premature end to the night! Now the truth is, and as Murphy’s Law dictates, anything that can go wrong, will go wrong eventually. While there are certainly steps that can be taken to minimise the risks, preventing disaster from striking altogether is simply impossible. What’s important is to be fully prepared for when it does. So when was the last time you actually sat down and took a long and hard look at what could go wrong with your equipment, and how it would affect the disco? There’s nothing worse than the sound of silence when you’ve got a packed dancefloor!

Most DJs I come across think they’ve got the whole ‘backup equipment’ thing covered, but probably haven’t given it enough thought to actually cover all of the bases. When you take that critical look at your setup, it’s amazing the number of things you’ll find that could actually go wrong. Let’s start by considering the electric – how many wall sockets do you plug into? For many DJs the answer is going to be just one – and they’ll justify that by telling you that “I don’t draw that much power as I use LED lighting”, but electric is a strange force. It’s certainly a force to be reckoned with, and it’s worth remembering that the only thing that allows the electric to power your equipment is a small ceramic capsule with metal caps at each end, and a very thin bit of wire inside the capsule connected the two ends – that’s right, our good friend the fuse in the plug.

There are actually many things that can cause a fuse to blow and they can even simply get ‘tired’ over a long period of use, especially if they’ve regularly used to carry their maximum load, and then just literally wear out. It’s not common, but when it does happen… silence!

So there’s the first hurdle, and your simple way round it is to carry some spare fuses, or at least a spare extension lead or two (which is probably what was attached to the plug that blew). But as I’ve said, there are many things that can cause the fuse to blow. One of the most common for DJs is probably a faulty piece of equipment, which might not be apparent until you’ve replaced the fuse – or extension – and plugged it back in, only to find that it immediately blows again. Now hopefully you keep your equipment in good condition and you check it, at least visually, each time you take it out to an event, which will help to minimise the risk of a fault developing. But by the very nature of what we do – regularly setting up, using, then packing down and transporting our equipment – knocks and bangs that could lead to a fault are inevitable. So my advice is to try to split your rig over two or more wall sockets. This will mean that if a main fuse blows you’ll not lose power to all of your equipment and you’ll also be able to more easily find the fault, as the number of possible culprits will be reduced.

Let’s take a look at the bigger picture now. Your setup is likely to consist of (basically) some lights, a music source with some kind of mixer or controller, and a pair of speakers – either powered or with an amplifier. Now the chances are (I hope) you’re going to have more than one light on your rig, so if one fails, the light show might suffer somewhat, but it won’t ruin the night. So let’s move on to think about your playout device, whether you use a twin CD player, laptop, tablet, or even – for those of you who’ve been around long enough to really appreciate music (or just happen to be that sort of DJ) – turntables. Decks can die, CD players can blow and, if you run from a laptop, we all know there’s a chance that it, or your DJ software, could crash. But, hopefully, as this is arguably the most important part of any DJ setup, you have something ready as a backup if your main playout system fails. Perhaps a second laptop loaded with a copy of your music collection, maybe a CD player with a collection of floor-fillers discs or even an iPod as an emergency backup.

But what do your playout devices plug into (both primary and secondary)? For most of us, that’s going to be a mixer of some sort, either a traditional standalone DJ mixer or one that is integrated into a MIDI controller for the software running on your laptop. What if that failed? The mixer/controller is actually one of the most essential parts of the setup. If that fails, how are you going to connect anything to anything? So what’s the answer here? The truth is, it depends – you could carry a spare mixer but it’s going to take some time – while no music is playing – for you to swap around the input and output leads. If you’re using a laptop connected to a MIDI controller, then you’re potentially talking a serious amount of time to reconfigure the laptop to not use the USB outputs, but instead to use the headphone socket to (somehow) connect to your backup mixer.

I think the truly professional solution is to actually always have both your primary and secondary playout system connected to your PA to allow an instant switch if either your main playout system on mixer dies. I’ll explain how I set that up on my rig shortly, but first let’s consider the final piece of the puzzle.

If you’re using an amplifier and passive speakers then it’s worth thinking about what would happen if it fails. You may be lucky and just lose one channel meaning that the music won’t die completely. This has happened to me and, fortunately, in that instance it was possible to daisy chain the second speaker from the output of the working one, and everything was ok. If you are using a single amp, a spare as back-up is essential in case it dies completely. Of course if this does happen you’ll still have a period of silence while you hook up the replacement, and it’s never any fun having to swap wires around while a room full of people stares at you wondering why the music has stopped!

A better idea is to always use both amps, with one running the left speaker and the other running the right, so that the music continues, albeit through only one speaker, if either amp dies. This also means that correcting the problem only needs one input connection and one output connection to be swapped. Of course if you’re running a pair of active speakers, you’ve also already got this level of redundancy in place. If one of your speakers fails, then the other one will probably get you by until the end of the gig, although there’s little chance of being able to daisy chain in that instance so carrying a spare active cab is a prudent.