It's a wise move, learning to use CDJs. And while using vinyl is a definite skill and one that can only be nailed with lots of practice, luckily CDJs are easier - and every digital DJ really ought to be at least capable of using them, at least in a basic fashion.
Why? Well, while nowadays you'll probably not be called on to DJ with vinyl at all, you may well roll up to a DJing situation where, for whatever reason, CDJs are your only option for playing a set.
So what are you going to do? Refuse the gig because you can't plug your beloved controller in? What happens if you're at an after-party and there's a CD DJ who's had enough, and you're there, burning for a set? Wouldn't it be nice to be able to just take over? Furthermore, I think it's true to say that a good DJ should be able to rock the party on any gear. While CDJ DJing is undeniably tedious compared to controller DJing because you're so limited in what you can do, that doesn't mean you shouldn't know how to do it.
So here are some tips especially for the controller DJ who's wisely decided it's time to get proficient with CDJs.
(These tips assume you can't just borrow a two-CDJ-and-mixer set-up, or even better, go to a bar or club and practise on one. I am guessing most readers can't.)
1. Plan how you're going to organise your tunes
One of the great things about controllers is that once you've got a system, navigating your playlists and music library is really easy. With CDJs, you're back in the dark ages. So make sure you've thought through how you're going to arrange your music. Of course, if you can use a USB key drive that's great, but it pays to have CDs burned and in your bag too, just in case. Remember, many CDJs won't accept USBs, some accept memory cards but not USBs, etc. Cover your bases.
Don't use rewritable CDs; use write-once to be sure they'll play properly. And don't burn the MP3s as MP3s to the disks, either; burn them as audio files, playable in anything. Again, covering your bases.
As you're not switching permanently to CDJs, just having them as a backup, you're obviously not going to burn all of your music, but a representative set of what you'll probably want to play. A good rule of thumb is to take at least twice as much music to cover any set you may be called to play (so for a two or three hour set, maybe six CDs-worth of material). This means you'll not spend all your time looking for tunes, but have enough to pick and choose.
If you're using USB drives because you know the club's CDJs have sockets, take two containing the same music, because you don't know how sophisticated the CDJs will be with regards to playing from the same USB. Plan for old, simple, half-broken equipment and you'll be covering your bases Finally, make sure your metatags are all properly up to date as non-tagged music is not going to be of much use to you when trying to locate it on a small LED screen.
2. Practise on your controller with no sync or waveforms
This is basically what CDJ DJing feels like. You can see the BPMs but apart from that, you're beatmatching by ear. And the easiest way to replicate this at home with a controller is quite literally to cover up the extra information that DJ software gives you by sticking bits of paper over your computer screen!
You'll soon realise that like it or not, you've come to rely on the visual feedback and on that lovely, simple "sync" button - and I'm sure you'll find it frustrating at first. But it's best to put in the practice long before you may need to call on the skills.
Plus, teaching yourself manual beatmatching in this way (which is basically what you're doing) is a good extra skill to have for so many other reasons as well.
3. Mock up some "CDJ players" at home
This is a step further, and it isn't as hard to do as you may think. If you have or can borrow a simple two-channel DJ mixer, and have a spare laptop or an iPad, then you can have a go at doing this. Here's how:
1. Set up your first laptop, plugged into one channel of the DJ mixer, with your DJ software running. For extra realism, put one of the CDs you've burned in the CD player and only play tunes from that CD (by navigating to it in your DJ software's browser), so you don't access your iTunes. This laptop is "CDJ player number one". As before, cover up the waveform information and don't use sync. Control this either with the keyboard shortcuts or your DJ controller - but remember, we're only using one deck of the two or four you have available
2. Do the same with another laptop running whatever DJ controller software you can find. Alternatively, if you have an iPad, use that - there's software out there such as MixmoDJ that can approximate a single CDJ on the iPad, which makes things even easier. Again use one of your CDs, or in the case of an iPad, have a playlist that is the same as the CDs you've burned to take with you. This iPad or laptop is plugged into the other spare channel on the mixer
3. Now, you plug your headphones and speakers into the DJ mixer, and you've basically set up two completely independent music sources (your "CDJs") and a mixer (which you'll use to mix the sources and to monitor them with in your headphones). Welcome to the dark ages of DJing! A few hours a night practising like this, and CDJs will feel positively streamlined and simple to use in comparison!
If you've never used a mixer away from your audio sources, this is valuable experience to get you used to how things have always worked for non-digital DJs.
(By the way, I believe that if you don't have a two-channel mixer, you should consider buying one, not only for this, but for general backup and DJ use anyway. Get one with a microphone input and I guarantee you'll find uses for it at various times throughout your DJing career.)
4. Read a CDJ manual
Nowadays, PDFs online let you really get familiar with equipment before you have to use it (or buy it, in fact). By reading a CDJ manual (I recommend one of the Pioneer CDJs as they're the ones you're most likely to come across) you'll learn the slight differences in basic cueing, how to set multiple cues, how to do looping (hint: it's often manual, so use your DJ controller's manual loop in / out points to replicate it for practise) and how to move through the tracks on a CD.
If you wanted to look at Rekordbox software (Pioneer's music library management system), a PDF manual will help too - and as you can now you can download Rekordbox for free, if you know you're going to be using Pioneer CDJs, it's probably worth the effort to consider arrange your playlists this way.
5. Keep it simple, stupid!
So once you're at the point of playing a CDJ DJ set, the key piece of advice, especially at the beginning, is to keep it simple. It's not the time for trying tricks or pushing the limits. Look at it this way: It's not actually so hard to play records, one after the other, using anything - including CDJs. So you're going to be able to do that bit OK.
One step up from that is simple beatmatching. Hopefully with what you've learned from this article and the practice you'll put in, that will prove reasonably straightforward for you. And at that point, as long as you're putting the effort where it is really needed (proper set programming), you'll have everyone in the room happy. It really is best to save the showing off for the next time you're DJing on your controller.
Good DJs don't let their equipment tie them down. If you're the kind of person who's always trying to perform crossfader cuts on the car stereo, who notices when tracks are perfectly beatmatched by complete fluke when you walk from one room with the radio on to another with a different station on, who tries to drop tracks on their iPhone to be in sync with music on the the TV just for lazy entertainment, who will happily DJ at a party from an iPod because you want the right records to be playing - well, if you're this type of person, you're going to be fine. That's because you have the right attitude to it all.
You realise that your controller, a club's CDJs, and yes even iPhones and iPads and other MP3 playback devices, are all just there to get the right tune playing at the right time. Conquering their technicalities is the easy bit: Picking the right record for right now is, as it always has been, the real challenge of the job.
Go in with this attitude, and sure, you may drop the odd mix - but you'll get a DJ set where otherwise you wouldn't have done, you'll have leaned loads, and you'll still have got the music right - which is the most important thing.
Are you a controller DJ who also used CDJs? Have you come from CD DJing to controllers? Have you ever had a gig where you ere forced to use CDJs because they wouldn't let you set up your controller? Please let us know your thoughts and experiences in the comments.