Alex & Sierra performed their unplugged song “Say Something” by A Great Big World feat Christina Aguilera on The X Factor USA Season 3 top 6 performance show, Wednesday night, December 4.

Watch their divas performance of “Say My Name” here.

Alex & Sierra X Factor Finalist

Judges comments:

Simon Cowell: My favorite performance of the season.

Paulina Rubio: I’m impressed.

Kelly Rowland: I thought I saw a performance on an awards show.

Demi Lovato: You two playing instruments was magical.

See recap and videos of tonight’s performance show here.

Watch the video below.