My September Scientific American column explores the push to replace live orchestras at operas and musicals with less expensive, but less satisfying, digital ones.

This issue affects me deeply, you see, because I wasn't always a technology writer. My original aspiration was to compose Broadway musicals.

After college I spent 10 years chasing that dream. While I waited for the world to discover my compositional genius I worked in the office of a theatrical licensing house called Music Theater International (MTI). Companies like MTI rent the rights, scripts and music for musicals such as Fiddler on the Roof or Les Misérables to your school or theater.

My boss was fascinated by the possibilities of exploiting technology to foster more live theater. We had a lot of long conversations about what that meant. For example, should we offer canned recordings of the orchestra parts for our shows? Then many more schools and theaters would be able to produce musicals. But we also didn't want to be in the business of discouraging the use of live orchestras.

In the end, we limited our offerings to tools for use in rehearsals. For each show, we developed a set of MIDI files (which perfectly reproduce an original keyboard performance) for rehearsal use only. Because these disks could play the entire piano part perfectly, at any tempo and in any key, they permitted choir teachers, directors and choreographers to conduct appropriate rehearsals—and even multiple rehearsals simultaneously in different rooms. But we still insisted that our productions were performed with live music.

In the 20 years since then the licensing companies have tiptoed closer to permitting digital playback at live performances. For many elementary and middle schools—whose student orchestras simply don't have the ability to play a full score—productions can rent a CD of the show accompaniment; audiences are understanding.

But what about regular adult performances? Some licensing houses, including Theatrical Rights Worldwide (TRW), offer both a rehearsal tool and software that let productions perform with a digital orchestra. "We encourage live performers and live musicians but we also look to promote and encourage the performance of our musicals," TRW president Steve Spiegel says.

So far, he says, very few professional productions rely on these digital playback offerings. "It's a small percentage, maybe 10 percent of the shows we license," he says. "Most of them haven't done musicals before. They're building a program. They don't have the budget or the musicians available. A lot of them are overseas."

Elsewhere, he says, when funding is tight, most theaters prefer to reduce the number of live players rather than use prerecorded tracks. "The good news is that the majority, by far, are only looking for something to get through the rehearsal process," Spiegel tells me. "The excitement of having a live orchestra can never be replaced. The audience expectation can never be replaced. The great majority understands the impact that the live musicians have in the theater world, and that's very comforting."