Bertoia arranged his favorite sculptures in a restored barn on his property in rural Pennsylvania and began performing with them. "He would play one, then let the sound taper off, then play another," Val says. "The sound would taper off very gradually. That's the beautiful part. It's very refined, going off into the distance."
Val Bertoia keeps the tradition alive today, creating sound sculptures of his own.
Trimpin, who says one of his goals "is always to visualize sound," falls into the category of sound sculpture as well. His mission goes beyond accompanying music with imagery, though.
"What ties it all together," he says, "is space."
Trimpin regards space as music's fourth dimension, after timbre, pitch, and time. He loves the music of the late Henry Brant, who divided his orchestras into groups that performed simultaneously from different sections of a concert hall to create a spatial dimension.
The German-born, Seattle-based artist who has dropped his first name (Gerhard) and won a MacArthur Fellowship genius grant, Trimpin has created works that range from 'Klompen,' constructed of 96 wooden shoes he bought at yard sales in Holland, to 'Liquid Percussion,' a toe-tapping piece that involves water dripping into hand-blown glass containers.
His most famous work is a 50-foot tower of self-playing electric guitars at Seattle's Experience Music Project.
Because Trimpin believes space is integral to his compositions, he doesn't release audio versions of his compositions. "You have to be there to experience it," he says. "You have to see it."
But visuals aren't necessary for all spatial sound art. Stan Shaff has been "choreographing sound in space"—in a pitch-black room—for more than 40 years at his Audium in San Francisco.
Another Bay Area artist who works with sound and space is Bill Fontana, whose 'Spiraling Echoes,' installed beneath the rotunda of San Francisco's City Hall in 2009, beamed auditory recordings of birds, foghorns, and aural souvenirs from the city by the Bay at passersby in the space, who affected the sounds through their movement. "An auditory dream," Fontana called it. Its only visual element was City Hall's extraordinary architecture.
Fontana's piece illustrates another major category of sound art—installations. Bertoia's first sound piece was a musical fountain for a mid-century modern shopping center in Illinois that sought "a deep reverberating sound, like that of many bells," according to Nelson. It proved a failure because, to handle the area's strong winds, he made the metal poles too stiff to vibrate properly.
Among present-day sound sculptures is 'Wind Harp,' a 92-foot tower built in 1967 by Aristides Demetrios and Lucia Eames (daughter of Charles and Ray Eames, the mid-century designers), in South San Francisco, and the monumental 'Wave Organ' in San Francisco Bay, by sound artist Peter Richards and stonemason George Gonzales. It uses stone tubes to amplify the sound of waves.