(CBS News) Pentatonix won over America's hearts on the a cappella singing competition TV series "The Sing-Off" last fall, and now the five-member group hopes to win over fans with its new debut EP, "PTX Volume 1."
"We knew at the beginning we wanted to do four covers and two originals," vocalist Avi Kaplan told CBSNews.com about the EP, which debuted in the Top 10 on iTunes last week. "We just kind of slowly started to pitch songs, and everybody would talk about the songs they want to do."
Nicki Minaj's "Starships" and Goyte's "Somebody That I Used to Know" are among the covers.
When Pentatonix performed at the NBA All-Star game in February, Minaj was among the other performers there.
"Chris Brown, Nicki Minaj and Lil Wayne all started standing up and dancing," vocalist Scott Hoying remembers. "Then Ne-Yo came up to us and said we were amazing ... Nicki Minaj thanked us."
The group members -- Kaplan, Hoying, beatboxer Kevin Olusola and vocalists Mitch Grassi and Kirstie Maldonado - all had a hand in creating the vocal arrangements on the new EP.
"When we're arranging, it is a very, very collaborative process ... we've done so many arrangements. We've done almost 30 arrangements in the year we've been together," said Kaplan. "We sit in a circle and go through every section of the song. Then we try something. If we don't like it we can scrap it and try something new."