The producer - who has worked with Madonna, Rihanna and Black Eyed Peas - teamed with the R 'n' B star on 'Without You', which he thinks is "perfect" for him because it mixes a ballad with club beats.
David said: "It's just totally emotional. Some of the record is a proper ballad, and then it goes to that crazy dance beat.
"It's perfect for him, because he's famous for his ballads. And he's also now famous for those big club records that he comes with. He's an amazing dancer, so I felt like he was the artist that I needed."
The duo previewed the track in Ibiza, Spain earlier this year and the crowd's reaction proved to them the song - which appears on David's 'Nothing but the Beat' album - will be a huge hit.
He added to MTV: "It was amazing. We were not supposed to do this. I always do these kinds of stupid things, playing records when I'm not supposed to play them. And Usher was so excited for this time to be in Ibiza performing in front of those people.
"He called me onstage and said, 'Come on. Let's do it.' So we did it, and, yeah, they loved it. We had to do it again! They asked for one more."