When we say "classical music," what do we mean by classical? In an era dominated by digital media, that question is becoming increasingly difficult to answer.

The sight of a string quartet onstage is not unusual, of course. But Thursday evening at Ordway Concert Hall, in the latest St. Paul Chamber Orchestra Liquid Music concert, we saw other, stranger paraphernalia. Two vibraphones, for instance, and some percussion conches. A rock drum kit. A large projection screen above the players. And stage right, two MacBooks on a table, one operated by Daniel Wohl, a French-American composer who was presenting his new work "Holographic."

The interface between traditional classical procedures and the brave new world of digital electronica is the central subject of the piece. Initially a CD project, "Holographic" was expanded to include a significant visual element, the kinetic images of Los Angeles-based visual artist Daniel Schwarz that accompany the eight self-contained movements.

Schwarz's input was initially underwhelming as the agitato figurations of the quartet launched the music, counterpointed by an anonymous on-screen fuzz resembling a badly scrambled television signal.

But the piece itself and Schwarz's visual glosses on it gained considerable impact as "Holographic" progressed. The anxious scuttle of monochrome Mondrian rectangles at one point locked tellingly into the grate and urban clank of Wohl's music. At another a constellation of sky-blue stars was sent shimmering into deep space, as bell sounds pealed in celebration.

Schwarz's extended sequence of Google Earth images hovering over an American landscape was especially suggestive. As the camera panned from open countryside to the soulless grid patterns of modern suburbia, water drops refracted the images, tear-like, and woozy glissandi in the strings appeared to mourn the brutal geometries imposed by humankind on the natural environment. It was a moving, resonant moment, symbolic of the uneasy interaction between the organic and mechanistic elements of 21st-century living that "Holographic" seeks to elucidate.

The last word, significantly, went to the string quartet, as the percussionists dimmed their lights for the final movement, and went silent. Were "classical" values of poise, dignity and reason reasserting themselves? Not quite. The harmonies were eerie, the melodies fractured, the textures floating in a ghostly electronic echo chamber. Music of seared beauty, still hopeful, but tinged with apprehension for an uncertain future.

Terry Blain is a Twin Cities music critic.