by: Todd Betzold

The second bracket of groups will be singing on tonight's The Sing-Off to fight to move on to another week of singing.

These six groups will also have two rounds to prove themselves: first round, reinvent one of today's hottest chart toppers and second round, they must re-imagine the biggest hits of the 1960s.

The show gets started with a group number with them all singing "Rhythm Of Love" by Plain White T's...a fun and upbeat start to the show.

The Deltones are the first group to hit the stage tonight. They'll be singing "Edge Of Glory" by Lady Gaga and they had a crazy week with changing arrangements and sickness among the members, so we shall see how they do on stage. The only thing sick on that stage was their performance. Great performance and great vocals.

Pentatonix is up next singing "You're Love Is My Drug" by Ke$ha and they will be doing some crazy arrangements with this song and changing it completely from the original...will it go over well? This was awesome...completely different from the original and very techno-feel to it and very entertaining.

Another group of solo artists, The Collective, is up next and they'll be singing "Rocketeer" by Far East Movement. Another group with sickness, as Rachel has acute laryngitis. Well, she powers through the song, but you could see her feeling the pain at times during the performance. It was a good job and great vocals, despite the sickness.

Vintage vocalists North Shore have to step out of their comfort zone with their first song, as the doo-woppers take on Bruno Mars' "The Lazy Song." For none of them listening to a radio in quite a while, this was a great song choice for them. They put their spin on it and had fun with it.

The Dartmouth Aires bring their song, "Animal" by Neon Trees, to the stage next. Michael, whose mother had a stroke last week, goes home for a couple days to be with her; so he has to play catch up...will it affect the group? His absence for two days had no affect, as they brought a lot of energy to the stage. Great vocals, choreography and entertaining.

The last group to come out is Sonos, which normally uses pedals to add to their songs. They will be singing "Viva La Vida" by Coldplay and nerves are going strong for this group, who feel this is do-or-die for them. It was a decent performance, but the song was too much for them. It is too well-known and the lead vocals lacked the power of what Chris Martin does for Coldplay.

Now it's time for the songs from the 1960s and Pentatonix kicks it off with "Piece Of My Heart" by Janis Joplin. They put their own mix to this classic and I enjoyed it, but it was weird in spots, but for only having five members (and only one girl) they do a great job.

The Deltones bring The Supremes back singing "You Can't Hurry Love." With this performance, I feel we go back to last week and how they are fun and cute, but that's it. Just lack something...no wow factor, just fun.

Up next, the only group that lived through the ‘60s, North Shore, hits the stage singing "Unchained Melody" by Righteous Brothers. This was a perfect song choice for them. They do it very well and put a little twist on the original....I really enjoyed it.

The Collective brings some soul to the stage singing "Hold On I'm Coming" by Sam & Dave. This was an awesome performance as well. So much energy...made me want to get off my couch and just start clapping and dancing. My favorite of the night (so far, but only two performances left)!

Performing Michael Jackson's first number one, Sonos chooses to sing "I Want You Back" by The Jackson 5. I enjoyed this performance. They made a ‘60s song very modern and I liked that...the judges didn't though...not good remarks from them.

The final performance of the night belongs to Dartmouth Aires singing "Pinball Wizard" by The Who. And we have a winner of the night: this was so fun, so energetic, so choreographed and so well done. They were very entertaining on that stage.

Now time for the sad news: who will be getting the boot. North Shore, Dartmouth Aires, Pentatonix and Deltones are all safe for another week. That leaves Sonos and The Collective left. Who will be heading home? The group singing their swan song tonight and heading home is Sonos, as The Collective gets one more week to prove themselves.

The Sing-Off airs Mondays at 8/7c on NBC.

(Image courtesy of NBC)

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