Pentatonix reflects on 2015: Performing for Justin Bieber, hitting #1 on Billboard chart

A-ca yes! Pentatonix has taken the world by storm with their incredible voices since forming in 2011 on NBC’s The Sing-Off. This year alone has been incredible for the a cappella group, which consists of members Avi Kaplan, Scott Hoying, Kirstin Maldonado, Kevin Olusola and Mitch Grassi. The vocalists snagged their first Grammy award, reached number one on the Billboard 200 chart and wowed a star-filled crowd with their tribute to Star Wars at the American Music Awards. Topping the year off, the group released their self-titled album Pentatonix along with a deluxe edition of their holiday album That's Christmas To Me.

The new year is already shaping up to be a great one for the recording artists. Pentatonix's holiday record has yielded yet another Grammy nomination for their arrangement of “Dance of the Sugar Plum Fairy.” To celebrate this Christmas season, the group will illuminate the Empire State Building on December 21 with their nominated track. HELLO! caught up with the Grammy-winning group at the NYC landmark to discuss their standout year and what 2016 has in store.

Avi, Kristin, Scott, Mitch and Kevin Photo: WireImage

HELLO!: Between the Grammy and AMAs what has been the biggest moment of 2015 for the group?
Scott Hoying: The most excited I’ve ever felt like in terms of like I was jumping up and down was the number one on Billboard. We fought for it all week and all the predictions kept saying 'you're not going to be number one, you're not going to be number one.' We kind of had settled with that but we kept doing all these like different interviews and meet and greets and trying to get the numbers up and sure enough we ended up with number one, barely, and it was just so exciting for us, and I think that was a highlight.

H!: Who’s the most notable person you've ever performed for?
All: Oooh!
Scott Hoying: As in terms of who we’re obsessed with — we just performed at the AMAs and there was a lot of people that we're huge fans of there. I mean the front row was Nick Jonas, Demi Lovato, Meghan Trainor, Justin Bieber, Ariana Grande. It was crazy to see that while we were performing.

H!: Your holiday album That's Christmas To Me is out. Is Christmas music your favorite type of music to cover?
Kristin Maldonado: I think it’s the most fun.
Kevin Olusola: I think it’s something that works really well for us. I think just a capella and Christmas time really works well.
Scott Hoying: Yeah, and our fan-base is such like a joyous, happy singing community, it's like Christmas music embodies that.

H!: Your other album, Pentatonix, has songs like "Cheerleader" and "Where Are You Now." How do you guys decide which songs you want to record?
Scott Hoying: Just songs we love!
Mitch Grassi: Those were songs that we really loved this year and songs everybody else loved too.

Pentatonix's Grammy-nominated track will light up the Empire State Building December 21 Photo: WireImage

H!: Do you all vote, ‘Oh were going to do this song?’
Kristin Maldonado: I feel like it generally becomes a mutual thing. We like all get obsessed with it. Like "Cheerleader," I feel like we kept playing it over and over again on our tour bus and so it was an obvious one.

H!: What was the inspiration behind the original songs on the album?
Kevin Olusola: Oh my god everything!
Scott Hoying: Love, touring, our journey the past four years, personal growth. I mean we wrote a million stories. We probably wrote 40, 50 songs in a couple months. Narrowing it down to 13 was the hardest thing ever.

H!: What are you all most looking forward to in 2016?
Mitch Grassi: I think just touring with the new music and singing our original music for crowds and having them sing it with us. It’s going to be really special.

H!: Do you have any New Year's resolutions?
Scott Hoying: I want to eat healthier.
Kristin Maldonado: Eat healthy, keep the motivation to eat healthy too. I feel like it goes in like spurts. I need to stick with it.
Kevin Olusola: I think the same.
Avi Kaplan: To be more productive.

The Empire State Building's holiday light show on December 21 — which features Pentatonix's holiday track — will simulcast on iHeartMedia’s platforms.