Answer:
It means that there are two or more male African singers singing in there highest register and the two people are singing different rhythms.
i hope this answer is what you want
pokemon952
i know this is not in the answer but please can someone comment hints of the bast way to answer questions
thanks
--EDIT--
You Could (Not Always) Start as A Full Sentence when the Question is a bit out of sense but since the Q and the A are close you don't need it. Your Answering was good.