Ashford and Simpson find it particularly gratifying to get close to their audience at their current gig.
The husband-and-wife team are appearing at the New York cabaret Feinstein's at the Regency through Sept. 29.
"You move differently than you do when you're filling the stage at Radio City," Nick Ashford told the New York Daily News in a story published Sunday. "You have to be bigger than life there. Here, the people can see every wrinkle in your face."
"When you're that close to the audience, it's like you're under a magnifying glass," added Valerie Simpson.
They have been top songwriters and singers since the 1960s and '70s, penning such classics as "You're All I Need to Get By" and "Ain't No Mountain High Enough" and recording hits such as "Solid."
The couple are also working on a musical adaptation of E. Lynn Harris' "Invisible Life," a gay coming-of-age novel.
"It says things people need to hear about being gay," Simpson said.
There's no one way to write a hit song, Ashford said.
"Valerie will play something. I'll sing some words," he said. "It can go from there. You just live your life and the music comes out of you. We write about our life, our experiences, our love."