“John is something of a watch-nerd icon,” said Benjamin Clymer, the 32-year-old founder of Hodinkee, which features watch news and reviews catering to next-generation aficionados. “I think, in a lot of ways, John made it O.K. to really go deep into watches and not be embarrassed about it. I can’t tell you how many guys have come up to me at events and said, ‘My wife or girlfriend thought I was crazy for caring about watches so much, until I told her John Mayer was the very same way.’ ”

It’s a ‘Syndrome’

Mr. Mayer’s own girlfriends have tended to view his watch obsession as a “syndrome,” the singer admitted.

Reclining on a white sofa in the Carlyle on a recent afternoon, Mr. Mayer, who was in New York for an appearance on “Late Show With David Letterman,” had that just-got-out-of-bed look. His rockabilly pompadour a bit mussed, he sat cross-legged, without shoes, wearing a black T-shirt and low-slung jeans by the Japanese streetwear brand Visvim.

“I think you’re born a watch person,” he said. “Even if you don’t own a watch for a while, you either get it or you don’t.”

He bought his first “real” watch, a Rolex Explorer II, not long after receiving his first “real” check from a record label, following the release of his 2001 breakthrough album, “Room for Squares,” which has sold more than 4.5 million copies.

“You take it home and you study and you wear it, and the first thing you notice is, ‘Whoa, this thing is heavy,’ ” Mr. Mayer said. “You’ve never felt weight shift like that on your wrist. It’s heavy in weight, but it’s also heavy in the sense that all these pieces are working together. It’s what I call the ‘density of design.’ ”