Blake Shelton and Gwen Stefani have only recorded together in the studio a handful of times, but he says he's "blown away" by her perfectionism and work ethic when it comes to recording.

The real-life couple recently scored a No. 1 hit country hit with their latest duet, "Nobody But You," and in a video he posted to Instagram, Shelton shared how impressed he's been every time they've worked together on a recording project.

"The thing that I think that I'm blown away by with Gwen is just how hard she works when she gets in the studio," he shares. "She's not willing to take anything less than greatness."

Shelton adds that Stefani will sing a song over and over and over, even to the point of exhaustion.

"I don't care if it means she's gotta get in there and sing 'til she completely loses her voice," he marvels.

"Nobody But You" appears on Shelton's latest album, Fully Loaded: God's Country. Shelton and Stefani first teamed up musically for a duet titled "Go Ahead and Break My Heart" in 2016, and again in 2017 for a Christmas duet titled "You Make It Feel Like Christmas."

Shelton and Stefani have recently purchased their first home together, a massive $13 million California mansion.

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