LOS ANGELES — Standing in the photo-lined hallway, you can almost hear the history.

One picture shows Frank Sinatra crooning into a sleek, silver microphone, his fedora tipped back. In another, Nat King Cole sits in front of a music stand in a crisp, white V-neck sweater.

Both were taken only a few feet away, a half-century ago, in the wood and glass studios of Capitol Records' famed cylindrical tower in Hollywood — familiar to tourists from around the globe as resembling a giant stack of vinyl records.

In this age of mp3s, digital home recording, and compressed and condensed tunes, the Capitol Studios remain a rare gem — a legendary yet working homage to high-quality sound, from Sinatra to the Beach Boys to Tim McGraw.

"It's not a historical monument to itself, it's a contemporary studio," said engineer Jim Scott, who recently recorded Dido with a 30-piece orchestra at Capitol.

But the large, three-room facility and its fabled subterranean echo chambers — whose sound, experts say, cannot be recreated — may soon be picking up some bad vibrations from an adjacent 16-story condominium and office project, part of downtown Hollywood's ambitious revitalization effort.

Sound engineers fear noise from the construction site, as well as from traffic that would eventually use the project's underground parking garage, will ruin the delicate aural qualities of the echo chambers.

A Los Angeles City Council committee recently denied an appeal by Capitol parent EMI Music North America and recommended approval of the project, contingent on a series of additional measures — including construction walls and a foam barrier — to mitigate potential sound issues. Capitol had worked out the measures with developer Second Street Ventures as a backup plan, though it still opposes the project.

"Capitol Records' executives are reluctant to keep open the recording studios and echo chambers if they run the risk of lawsuits from recording artists and their record labels," EMI's attorney John Whitaker said at the hearing.

David Jordon, co-owner of Second Street Ventures, said he felt confident that the measures would protect Capitol Studios' signature sound.

"We have no desire to create any negativity toward Capitol Records," he said. "Our design is to enhance and protect this iconic building and the area around it. From a personal standpoint, we wouldn't want that kind of liability."