Pentatonix is a chart-topping, Grammy-winning group of a cappella vocalists who began building an audience in 2011, while competing on the American television program The Sing-Off. The group was formed in Arlington, Texas, where baritone Scott Hoying, tenor Mitch Grassi, and mezzo-soprano Kirstin Maldonado first sang together as high school students. After earning attention on YouTube with their cover of Lady Gaga's "Telephone," the friends added bass singer Avi Kaplan and beatboxer Kevin Olusola to the lineup and subsequently auditioned for The Sing-Off. With a contemporary sound that included pop, dubstep, rock, and hip-hop, Pentatonix won the TV competition and released a debut EP, PTX: Vol. I, in 2012. The group's next four EPs — PTXmas, PTX: Vol. II, PTX: Vol. III, and PTX: Vol. IV — all became Top 10 hits on the Billboard 200 during the following two years. Meanwhile, the band's first full-length holiday album, That's Christmas To Me, climbed to Number 2 in October 2014 and eventually went double-platinum in America. The self-titled Pentatonix went to Number 1 the following year, as did A Pentatonix Christmas in 2017. Hailed as the one of the most popular a cappella acts of all time, Pentatonix won Grammy Awards for the group's renditions of "Daft Punk," "Dance of the Sugar Plum Fairy," and "Jolene," the latter of which also featured the song's original performer, Dolly Parton. Kaplan left the group after the release of A Pentatonix Christmas and was replaced by Matt Sallee, who made his official debut with 2018's PTX Presents: Top Pop, Vol. 1. The revised group released another seasonal record, We Need a Little Christmas, in late 2020, then returned the following year with an album of original material, The Lucky Ones.