Pentatonix (abbreviated as ‘PTX‘) is an a capella group with 5 members: Scott Hoying, Mitch Grassi, Kirstin Maldonado, Avi Kaplan, and Kevin Olusola. They started their career by competing in The Sing-Off, a singing competition for a capella groups, in which they won the third season. From The Sing-Off, their career started to rising after their debut