This time around on “Rhythm Roulette,” we get to see Brooklyn’s own, El P. The Def Jux general blesses us with the opportunity to gain some insight on the process, which has helped him make classic material since 1993. After heading to a hole-in-the-wall record shop and picking out some dusty old warped records, El shows us how to make something out of nothing, starting with his rusty, self-fixed, ASR-10…