Short for “sync”, the sync button works by allowing the DJ to automatically match the rhythms between two different tracks. This is done using a DJ controller or laptop while using one of the different types of DJ software equipment. Crossfading is a technique for moving from one song to another during a mix, which is used in conjunction with the combination of rhythms. The usual pattern of mixing music is to play a single song, incorporating a second song so that the two songs play simultaneously, and then attenuating the first song so that only the second one plays.
The rhythm sync button option is incredibly useful and is certainly worth considering, as it gives you the confidence to be able to mix a couple of tracks until it's an excellent backup plan in case of emergency. The previous section explains how to convert one song to another, but it doesn't explain how to align the two songs to produce a good mix. Whether you're learning and don't have the perfect combination of rhythms, if you're dealing with faulty equipment, or you just don't have time to do it manually, knowing that with just the push of a button you can use the synchronization function gives you an enormous sense of peace of mind and security that everything will work out. The most established DJs usually use the sync button to better offer them the ability to interpret more complex and creative DJ performance options when transitioning between the two tracks.
By having the sync button as an option, the DJ can have the right amount of mental space and, at the same time, better conserve his energy when it comes to matching the rhythms and using it more for other more important things, such as keeping the audience interested in performing. The main reason why someone resists the beat sync feature is that it can ultimately make a DJ think they really know how to play when, in fact, they're just pressing a button. Meanwhile, younger DJs have almost always had automatic rhythm synchronization options from the start and may have never needed to mix by ear. By knowing how the sync button works, what its advantages and disadvantages are, and when is the optimal time to use it, you can decide for yourself if you prefer to spend time learning and using the combination of rhythms by ear to get a better and more accurate sound, or take a little risk for a faster and more automated process using the sync button.
In these cases, you'll find it incredibly difficult to beat organically without using the beat sync button. When you want to synchronize two tracks, make sure that the Master button is selected, as this will ensure that the second track has a BPM reference point appropriate to that of the first track. For example, while most newer DJs don't usually have problems with the sync button and its use, the same is not true for older DJs who have been on the market for a while and haven't learned how to use some of the newer features offered in DJ equipment. In these cases, the BPM will be a bit erratic and not “perfect”, a rhythm synchronization software will have a really hard time trying to align the two tracks with each other.
While this isn't going to be the main reason for using the sync button, it will force all types of DJs to use it, regardless of what they normally think about it. Finally, when it comes to speaker and monitor issues, this is another time when virtually every DJ will opt for the sync button instead of trying to sync them manually.