“We’re getting calls almost every day from developers,” Mr. Imamura said, “so the fact we’re ignoring them says something about our intentions.”

There was hardly any interest in the building in 1975, when it could be had for a song. The Con Edison plant, which had provided electricity for the old Ninth Avenue el, had been converted into studios for “Let’s Make a Deal,” the old game show, but the production company went bankrupt. New York City seized the property for unpaid taxes.

Mr. Bongiovi agreed to pay off the $312,000 lien, and the city even furnished the mortgage. Still, he had to move out of his apartment and live in the building. “Every cent I had went into the studio,” he said.

At the time, most studios were carpeted “dead” spaces, with little of the trademark echo that gave Motown studios their warmth. Having cut his first records in Detroit, Mr. Bongiovi wanted to recreate that sound in New York; he came up with an innovative system of pine slats and burlap panels in unconventionally shaped rooms that today could be mistaken for Frank Gehry-designed saunas. (One corner of Studio C, however, features vinyl flooring and cork walls, an almost exact reproduction of Motown’s Snake Pit studio).