Sentence:  But musical ancestry aside, the influence to which Bieber is most beholden is the current trends in pop music, which means Believe is loaded up with EDM accouterments, seeking a comfortable middle ground where Bieber's impressively refined pop-R&B croon can rub up on techno blasts and garish dubstep <WSD>drops</WSD> (and occasionally grind on some AutoTune, not necessarily because it needs it, but because a certain amount of robo-voice is expected these days). 
Meaning of the word marked with <WSD> tags:  A point in a song, usually electronic-styled music such as dubstep, house, trance or trap, where there is a very noticeable and pleasing change in tempo, bass, and/or overall tone; also known as the highlight or climax.