The Sing Off 3 - 3rd & 4th Eliminations (Group B) + Special Appearance by "Committed"

This is the 3rd and 4th eliminations for the second group of 8 singers this week and that means 2 groups will be cut...were the right ones eliminated?

Will it be Pentatonix, Dartmouth Aires, Sonos or Messiah's Men in the first group?
Will it be Soul'd Out, North Shore, Deltones or The Collective in the second group?

Plus a special appearance by Committed, the second series group winner giving a sample of one of their newest songs on their upcoming album

The first eliminated group sang "Swing Low, Sweet Chariot"
The second eliminated group sang "Mama I'm coming home" by Ozzy Osbourne (i thought this should've been their main song)