Stephen Vitiello is a composer and sound artist. In 1999, he worked in a studio on the 91st floor of the World Trade Center. For six months he recorded the noises of the building and its surroundings.

At first, he’d hoped to capture the sounds outside his window — turns out, it wouldn’t open. So he pressed his microphones to the glass and used “the mixing board and equalization to zoom in on certain frequencies,” he explains. As the sound began to come into focus, “It was shocking — the first thing I heard were church bells.” Produced by Michael Raphael.

(Originally aired: August 31, 2002)