Aguilera is currently judging the second season of the NBC reality show along with Cee Lo Green, Adam Levine and Blake Shelton.
The 31-year-old singer wore a marigold Roland Mouret tight-fitted dress paired with spiked Christian Louboutin high heels on Tuesday night, where she had to eliminate two members of her team.
She told Us Weekly: "I like to keep it fresh and interesting. I get bored and I'm an artist first and foremost.
"I'm from the world of making videos and touring and I love theatrics.
"That's why sometimes you'll see me with a hat, sometimes you'll see me just a little more subdued like [Tuesday]."
Earlier this week, Aguilera revealed her plans to release a new album later this year - a follow-up to 2010's Bionic.
Watch a clip of The Voice's first live results show for season two below (US only):