As jobs go, there's not much to recommend it. The work is hard, there's no glory, and the risk of disaster is high. Regarding any levity, only the paycheck might draw a laugh.

And yet, page-turners are classical music's anonymous heroes. In some performances, a smart music reader with quick reflexes and intuition for nailing just the right moment for turning the page can be the difference between a performance fraught with gremlins and one that soars.

Page-turners are the air-traffic controllers of music, says Miles Cohen, artistic director of the Philadelphia Chamber Music Society, perhaps the area's most frequent professional employer of page-turners. "Both jobs require great skill and are semi-thankless," he says. "The only time anyone takes notice of what you are doing is when something goes terribly wrong. The more perfect one is at turning pages or being an air traffic controller, the less we even notice they are there."

There they are, and there, perhaps, they go. More and more players are being lured by the glow of the screen, turning to iPads and laptops in lieu of the printed page. The human page-turner may one day be turned out of a job.

"To me, the practice of using a page-turner is a charming relic of an amateur age, when chamber music was largely played by amateurs for amateurs in an amateur setting," says pianist Ignat Solzhenitsyn, who will use an iPad in a PCMS May concert with the Aizuri Quartet. "Today, page-turning - and it is a role I have performed countless times myself! - is an unwelcome anachronism, putting the pianist constantly on the defensive against potential catastrophe, so that his mind is bent more toward the person to his left than the people to his right."

Some, however, are able to transcend the hazard of the craft. Yung-Chen Lin, who has been turning pages for two decades, says she does it because, to her, these artists are celebrities, and page-turning is a chance for her to get close to celebrity. As a pianist herself, she also finds that she can learn from them by asking questions and by listening to their sound: "What I can hear sitting next to them is different than sitting in the audience, and I can use that sound when I practice."

"She is as close to perfection as it gets," says Cohen on Lin. "I have never once heard an artist complain, and often they rave about her skills just after the concert finishes."

But not every pager-turner has her acumen.

"I have too many horror stories of human page-turners. Their nervousness had a way of transmitting to my own performance. And some of their blunders could be absolutely catastrophic," says pianist Hugh Sung, a pianist and author of From Paper to Pixels: Your Guide to the Digital Sheet Music Revolution. "I hated the idea of ceding control of a performance to someone else's hands."

Among the more dangerous types: page-turners so slow they block the music, or so clumsy they turn to the wrong page; page-turners whose perfume distracts, or whose ties or necklaces get tangled in the pianist's hands; page-turners who say they can read music, but really can't.

Sung hated leaving so much to fate, so he went paperless 15 years ago, co-founding Air Turn, which created wireless page-turning pedals for musicians that send a signal to the computer when the player is ready for the next page.

"Once the technology caught up and page-turning pedals matured," he said, "the entire page turning experience became 'invisible.' I stopped thinking about the page turn, and could then focus entirely on the music. I never want to go back to relying on human page-turners."

In this instance of computers taking jobs from people, any cost savings isn't much. Page-turners locally earn $50-$100 per job, depending on whether a rehearsal is required and the complexity of the program.

But there are other benefits that come with using an iPad, says Nicholas Photinos, founding cellist of Eighth Blackbird, a contemporary music sextet who made the switch to all digital, whenever possible, about six months ago. The screen is lighted, so stand lights aren't needed. The app they use, forScore, comes with a metronome and tuner, and allows easy downloading from Google Docs.

Not that technology is flawless. On occasion, Photinos says, the Bluetooth signal between the peddle and laptop goes astray. Even so, "the fact that you can touch one part of the screen and turn it, it's still easier," he says.

Nicholas Kitchen, violinist with the Borromeo String Quartet, which lays claim to being the first string quartet to use laptops on the concert stage, points out another benefit of looking at the music world through your laptop: The establishment in 2006 of the International Music Score Library Project, where scans of original manuscripts and other editions from libraries around the world are accessible for free.

Says Kitchen: "One scanning process and a generous attitude of the library and everyone on earth can look at all the Beethoven Razumovsky quartet manuscripts or hundreds of others, a process that I can tell you personally has yielded one happy shock after the other to see the exquisite details of information that Beethoven puts only in the manuscripts - they do not make it to printed music."

As music publishers catch up, Photinos points out, they can send out updates to correct mistakes, and offer other features like different options for fingerings and bowings in string parts.

"I wouldn't be surprised," he says, "to see in 10 years orchestras putting their entire libraries on computer and sending out all the parts to the stands."

On the other hand, classical musicians aren't known as the earliest of adopters. Says Solzhenitsyn: "There is the look/feel/smell of paper books, which means a great deal to most of us over, say, 20 years of age. We can't quantify it. But we are loathe to part with it."