Inside the lobby of Kresge Auditorium, electronic buzzes, blips, and strains of melodies bounce around the foyer. A crowd of children, parents, and MIT students is trying out an assortment of handheld musical toys and composing software about to be featured in the sold-out United States premiere of Tod Machover's Toy Symphony. The performance pairs music professionals with children who have never studied the art, a traditional orchestra with fanciful musical toys, and the work of seasoned composers with that of inexperienced preteens.

At one end of the lobby, a volunteer shows three MIT students how to play Music Shapers, grapefruit-sized, cloth-covered instruments decorated with conductive embroidery; squeezing them changes the timbre of preprogrammed electronic musical phrases. Across the room, another volunteer "conducts" a group of seven children playing softball-sized ladybugs known as Beatbugs, which have touch-sensitive shells and are connected by cable to a central computer. A child taps a rhythm on the drumlike Beatbug, and the computer randomly sends it to another child, who adds another rhythm to it. On half a dozen laptops around the lobby, people compose complex pieces of music for what sounds like a string orchestra, using a software program called Hyperscore.

Machover-"America's most wired composer," according to the Los Angeles Times-is well known for his digitally enhanced acoustic instruments, called hyperinstruments. But with the Toy Symphony, which debuted last spring in Ireland, Scotland, and Germany, he and his group in the Media Lab have turned their attention from virtuosi to children. The group hopes to introduce children to complex and subtle aspects of playing music that usually take years to learn on traditional instruments. Machover is driven by the belief that music has become background noise in most people's lives. Through the toys, Machover says, he's "basically trying to say, Look, if you like music, it will be a much more powerful experience if you just get in there and experiment with it, take it apart, put it back together, make it yourself.'"

With this in mind, the group first set out to create a Music Toy that would be physically inviting. "I really wanted something squishy, that you could pull and twist," Machover says. After an assortment of experiments with foam, touch-sensitive mechanical devices, and even Silly Putty, the group chose a metallic thread that can respond to the body's electrical properties, registering touch. The result was the Music Shaper, which a player can use to manipulate just about any sound. For example, in the Cambridge performance of the Nature Suite, one of the components of the Toy Symphony, four children accompanied the orchestra on Shapers playing sounds such as owl hoots and gusts of wind. The devices allow players to experiment with musical qualities such as timbre, density, and structure in a visceral way, but according to Machover, they also teach kids something about conducting-how to shape music, give it form, and keep it moving.