You’ve definitely heard Pentatonix before, even if you’ve never heard of them. One of their many viral YouTube videos covering pop hits has definitely come across your Facebook feed at some point.

Pentatonix members Avi Kaplan, Scott Hoying, Kirstin Maldonado, Kevin Olusola and Mitch Grassi combine vocal talent with unheard-of musical mashups that incorporate interesting elements including beatboxing into traditional a capella arrangements.

Related: Pentatonix Drop The Covers On Their New Self-Titled Album

They’ve come a long way since their first YouTube video, uploaded three years ago, which shows the group singing Maroon 5’s “Moves Like Jagger." What followed was a whirlwind run on American a capella singing competition TV show The Sing-Off, on which the group won first place in 2011. Since then, they’ve released four albums, including a Christmas record that went RIAA Platinum and MC Gold.

Below, 10 of our favorite Pentatonix covers.

Lady Gaga - "Edge of Glory"

Before the group got wise to the wonders of video editing, all they had were their voices in perfect harmony and a single camera shot. In this one they’re literally sitting on a kitchen counter belting out Gaga's empowerment anthem.

Whitney Houston - "How Will I Know"

They’re just posted up in the foyer of one of their apartments or something – it's that casual. It reminds me of the videos that my friends and I in college would make with dancing and singing routines when we drank too much—except, you know, these guys are actually really talented.

Beyoncé - "End of Time"

This song has so many layers and percussive beats in the background, it lends itself extremely well to the a capella arrangement. The addition of the beatboxing takes it to a whole other level. Especially the call-and-return part of the song at 1:20 (“Boy, come to me…")

Nicki Minaj - "Starships"

How often do you hear rapping in a capella songs? The balancing act of spoken word and making non-lyrical music with your mouth is impressive. The dubstep-y bridge added helps make the song entirely their own.

Katy Perry/Justin Bieber - "As Long As You Love Me / Wide Awake"

Pentatonix starts to get fancy with mash-ups here. This combo of Katy Perry and Justin Bieber may have been one that nobody asked for, but the sounds mesh unexpectedly perfectly, especially the chorus where Justin’s lyrics lay over the beats from "Wide Awake" and the back-and-forth of the verses between songs.

*NSYNC Medley

Just in case two *NSYNC songs being mashed up wasn’t enough for you, how about whole medleys? Pentatonix was definitely gunning for the millennial crowd with this megamix of our favorite hits, from "Pop" to "Bye Bye Bye" and back again.

Justin Timberlake - "Pusher Love Girl"

Not only is this a very underrated JT song, it also works well for a capella. Timberlake is a noted fan of beatboxing himself, if we recall correctly from when he rocked our bodies back in '02. The song blends together a lot of different funky beats in the background, and hearing them recreated by people puts a new and interesting spin on the sound.

Lorde - "Royals"

The covered-to-hell-and-back song was given the Pentatonix treatment in a theatrical, sparkly video. Instead of appearing all at once a group as per usual, each member gets their close shot. This is the first time that I’ve seen an a capella group give me “yes, we’re an actual group” in a music video.

The Evolution of Beyoncé

Oh yes, they did. Starting with "Bills, Bills, Bills" and ending with "Halo," Pentatonix works their way through Bey’s catalog of hits and gets us misty-eyed and nostalgic in the process. Going from "If I Were A Boy" right into "Single Ladies" is essentially the a capella equivalent of this iconic GIF.

Jack Ü ft. Justin Bieber Cover - "Where Are Ü Now"

The original song is heavily produced and very electronic, so the fact that Pentatonix took a stab at covering it with actual human voices was ambitious. This slightly toned-down, moodier version of the banger is an impressive take.

Check out Pentatonix's original track "That's Christmas To Me" as part of Logo's "Happy Holigays" programming.

For more clips of Pentatonix singing holiday favorites, keep watching Logo all month long.