PITTSBURGH—One hundred people will use their laptop computers to make beautiful music together, even though they may be as distant from each other as Connecticut is from New Zealand.  Connected only by tenuous Internet links, the musicians will simultaneously create this unprecedented concert on their individual laptops, under the direction of Carnegie Mellon University’s Roger Dannenberg.

Dannenberg, CMU professor of computer science, music and art, will serve as “semiconductor” of the Global Network Orchestra. He will lead the collective performance from 12:15 to 1:15 p.m. ET March 1 at the Ammerman Center 14th Biennial Arts and Technology Symposium at Connecticut College.

A second concert site open to the public will be Rashid Auditorium in CMU’s Gates and Hillman centers in Pittsburgh and will feature Janelle Burdell, a professional drummer and percussionist who has performed with the likes of the Grateful Dead’s Mickey Hart, Herbie Hancock and the Shirelles.

The other performers will be at sites scattered across the United States, Europe and beyond, including Malaysia and New Zealand. Many of these musicians may be by themselves, but the entire concert with the contributions of all 100 musicians will be created in each of their laptops.

Everyone can listen via a webcast hosted by the CMU School of Music at http://music.cmu.edu/pages/webcasting/.

Laptop computers, as well as smartphones and tablet computers, are being used by music researchers to explore new ways of generating and manipulating musical sounds. A number of musicians have organized laptop orchestras, many based at universities. Two years ago, Dannenberg led a performance of the Federation of Laptop Orchestras that united about 50 musicians at six concert sites.

Though technically challenging to meld performances separated by thousands of miles and the associated time delays, “it went better than I expected,” Dannenberg said. “I thought it was actually very musical and I found it very rewarding.”

That experience inspired the latest effort. This time, the technical challenge of creating audio links with 100 separate musicians proved insurmountable, particularly with less-than-ideal Internet connections to some sites.

“Just the idea of streaming audio among 100 sites is out of the question,” he said.

So Dannenberg and Tom Neuendorffer, a longtime collaborator who now is principal engineer at Carnegie Speech, developed a system in which the musicians will not stream audio of the sounds they create, but will just transmit the control information — the keystrokes they use to create the sounds. These keystroke signals, which require far less bandwidth than streaming audio, will be shared across the entire orchestra, enabling each musician to simultaneously create the concert in their own laptops.

Dannenberg will lead the orchestra using scrolling graphical scores, similar to those used in the Guitar Hero music games or a player piano roll. He also will include directed improvisation and will split the orchestra into four groups at some points.

Small-scale tests of the concert software have been encouraging, Dannenberg said, but the concert itself will be the final test. “It’s never been done before,” he noted, “so this promises to be a great adventure.”

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