The BeatRoll DJ Switch Trick
Club mixers, such as the Pioneer DJM 800 or DJM 900, have a built-in FX section with a variety of selectable FX. The effect that we’ll be using is the Roll/Beat Roll effect, which is very similar to Traktor’s Beatmasher effect. The Roll effect can be used to create little glitches or loop rolls to throw into a mix. However this effect has a more utilitarian use that can help transition between DJs that need to share the same soundcard.
By setting a high beat/loop count (8/1, 4/1) DJs can create a seamless loop that’s playing right inside the mixer. This loop will continue to play until the Roll effect is turned off. Once the loop is set, the current DJ can unplug from the mixer or soundcard and the loop roll will continue to play from the mixer. This allows the other DJ to plug their laptop into the soundcard or mixer and mix out of the beat roll loop without any interruptions in the music.
There’s a lot of other important things to consider when switching DJs, be sure to know“basic DJ etiquette”.
Bonus Tip: Applying Color FX
If the transition is taking too long, the loop can start to sound really repetitive. DJs can apply FX overtop the loop such as the color FX of the DJM 800/900 to add some flavour to it. Another cool trick that can be used for transitions is shortening the loop roll length and applying color FX (such as echo) to create a dramatic build out.
source: DJ TEch tool