Pentatonix / Pentatonix.

Enhanced descriptions from Syndetics:

Genre-bending a cappella ensemble Pentatonix first came to audiences' attention during their winning run on the third season of NBC's The Sing-Off in 2011. Since then, Pentatonix have retained a loyal following, living up to the reality show hype with a distinctive brand of vocal pop that touches on rock, R&B, and EDM, all without the aid of any instruments. Despite their unique style, as with most of their a cappella peers, they've largely concentrated on applying it to cover songs. That all changes with the release of their self-titled 2015 album, which consists of all-original material. The move makes a lot of sense. In a post-Glee, post-Pitch Perfect world, the gimmick of an a cappella group in the pop sphere is becoming steadily less ridiculous. And Pentatonix certainly do all they can here to deliver a mainstream pop album designed to sit on the shelf next to works by Maroon 5 and Beyoncé. Perhaps not surprisingly to longtime fans, they've succeeded, and cuts like the exuberant "Sing" and the slinky "Ref" are infectious, dance-ready numbers that will most likely appeal to most fans of contemporary pop music. Also working in Pentatonix's favor is their ability to trade lead vocal parts from song to song. This means that the group can move between genres without sacrificing strength, leaning on the talents of one member for a gospel-tinged song, and another for something EDM. Also adding a modern flavor to Pentatonix are guest vocalists Jason Derulo on "If I Ever Fall in Love" and Tink on "Can't Sleep Love." Thankfully, Pentatonix haven't forgotten their roots, and tracks like "Cracked" and the stately "Take Me Home" are nearly pristine in their deft a cappella arrangements. Ultimately, by moving away from cover tunes, Pentatonix have helped push the a cappella style even further into the pop spotlight. That the only instruments they've used to do it are their voices makes their achievement all the more impressive. ~ Matt Collar