With the success of 2012's hit movie, "Pitch Perfect," and Anna Kendrick's foray into a cappella, we've seen the genre gain some interest, but Pentatonix gave the old school genre a new school twist with their 2011 debut after they won NBC's "Sing Off" TV competition for their a cappella arrangement of "Eye of the Tiger." Today, they're turning it up with their a cappella covers of "Somebody I Used to Know," by Goyte, "Gangnam Style," by PSY and "We Are Young" by Fun. Don't miss their stunning LIVE performance! Buy your Pentatonix tickets now!