We can watch videos of our whole journey - from old tours to doing the AMAs (American Music Awards) in 2013 and through the 'Star Wars' medley or when we sang with Stevie Wonder on the Grammys. I just sit back and say, 'I can't believe we did all this!'

Uh, I think so many things have happened in the mainstream that definitely brought awareness and attention to a cappella. The 'Pitch Perfect' movies, 'The Sing-Off' - I mean, the college a cappella scene definitely has become really hot, which is definitely wonderful.

Christmas and a cappella - what we learned really, really well is that they go extremely well together.

Kevin Olusola Quotes