First, ask yourself if you really need to do that kind of transition. Do the 2 tracks really work together? That should be your focus. If they do, and you need to make the transition, you could do as U31 noted and just cut/drop. You could also use effects—for instance, the delay with a freeze on the final beat so that it echoes in a satisfying way and bring the moombaton in when it sounds right. Finally, there’s no harm in simply letting the electro tune end or fade and then bring in the slower track. Everything doesn’t have to be a smooth transition, and sometimes no transition at all is fine. No one’s going to give you a failing grade on your DJ report card if you just let a tune end, and sometimes it actually sounds quite good.
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