An a capella group that officially began their singing career after winning Season 3 of "The Sing-Off," the group consists of Scott Hoying (baritone), Kirstie Maldonado (soprano/alto), Mitch Grassi (tenor), Avi Kaplan (bass), and Kevin Olusola (beatboxing percussionist). Pentatonix derives their name from the number of members in the group and from the pentatonic scale in music theory, with the c changed to an x for stylistic purposes. The group first began with the original trio of Scott, Kirstie, and Mitch from Arlington, Texas who decided that in order to effectively compete in "The Sing-Off," they needed a bass and beatboxer. Kevin (beatbox) was found by Scott on Youtube after watching Kevin's video of him beatboxing while playing the cello. Avi (bass) was contacted by the trio and joined up after seeing the three in a Youtube video. After winning on Season 3, the group signed a record label and was soon touring the United States. Their specialty is doing covers of popular music while adding in their own special breakdowns and futuristic musical effects, thanks to Kevin and Avi, with Scott, Kirstie, and Mitch focusing on melody and harmony. Some of their most popular covers are "Video Killed the Radio Star" by the Buggles, "Dog Days Are Over" by Florence and the Machine, and "Aha!" by Imogen Heap.