Randy Merrill is an American mastering engineer who has worked with international artists including Blink-182, DAY6, Lady Gaga, Katy Perry, Maroon 5, Harry Styles, One Direction, Adele, Imagine Dragons, Beck, Liam Gallagher, Jonas Brothers, Muse, Cage the Elephant, Maren Morris, Ariana Grande, Mumford & Sons, Paul McCartney, Troye Sivan, Taylor Swift, Lorde, Justin Bieber, Porter Robinson, Ayumi Hamasaki, BUCK-TICK, King Gnu, Little Mix and BTS.