Click here to watch a video report about the Science Museum's Listening Post

You walk into a white room in a fashionable Oxford art gallery. A fractured, fragmented version of the Moonlight Sonata echoes from an unmanned grand piano at one end. On the opposite wall is a white-on-white neon display of a telephone number. You dial, then listen. Down the line, you hear a whooshing, splooshing sound. You are connected, live and in real time, to a glacier melting in Iceland.

Meanwhile, at the Science Museum, in west London, displayed on a huge futuristic grid, you can see and hear thousands of messages sent by strangers in internet chat rooms all over the world as they are intercepted, live, in a work aptly entitled Listening Post. And soon, in a warehouse in central London, you will find five grand pianos, insides out, playing on their own over the disembodied voices of William S Burroughs, Claude Lévi-Strauss and Malcolm X. This is the splendidly titled Stifter’s Dinge, created by a German composer called Heiner Goebbels. It, too, is a work of sound art.

Remember when art appreciation used to be a simple, straightforward affair? You walked into a gallery, looked at some pictures, or maybe a few sculptures, and that was that. Then came photography, followed by film, the emergence of performance art and all that conceptual stuff with unmade beds, pickled sharks and rooms full of oil. Now, thanks to 21st-century technology, sound art – art for the ears, as well as the eyes – is bringing a new dimension to the art world. And it has moved way beyond its origins in avant-garde music, bringing an innovative approach to traditional subjects such as nature, landscape and human relationships.

The white room at Modern Art Oxford is half of the first solo show by Katie Paterson, a recently graduated Slade student whose extraordinary interactive installation, Vatnajökull (The Sound of), sponsored by Virgin Mobile, shares space with the result of another innovative sonic experiment, Earth-Moon-Earth (Moonlight Sonata Reflected from the Surface of the Moon). The 26-year-old Scot painstakingly translated Beethoven’s composition into Morse code, then fittingly, transmitted it to the moon, where it was reflected to earth again. She translated the resulting transmission – complete with missing parts where the uneven surface of the moon caused an imperfect reflection after the code’s 240,000-mile journey – back into a musical score and had it recorded (missing “moon-altered” bits and all) for an automated Disklavier piano. “The work is about evoking a sense of sadness at the disappearing world,” she says. “It’s disappearing while you listen to it, so it’s quite existential.”

In an inspired pairing, Paterson shares the exhibition space with the American landscape photographer Ansel Adams. For the gallery’s senior curator, Suzanne Cotter, they represent two sides of the same coin, with Paterson using modern technology to find the poetry in landscape that Adams captured through his camera lens. “There is an obvious resonance with the notion of landscape,” Cotter says. “On the one hand, we have classical 20th-century modernist photography by an artist who was an ardent conservationist [Adams], and on the other, we have a new artist [Paterson] using modern technology to tap into similar subject matter, and finding a poetic element in it.”

Paterson was not interested in streaming the glacier’s sound. For her, the intimate one-on-one relationship with each individual caller is everything, and her decision to withhold the image is a vital part of that emotional connection. “I’m trying to create an imaginary space the ‘viewer’ can enter into, using the sounds to evoke the visual rather than presenting them with an image,” she explains.

Meanwhile, at the Science Museum, Listening Post also utilises technology to create poetry: in this case, a kind of symphony of sound and vision conjured from text fragments and synthesized voices, culled from the randomly generated output of thousands of global web surfers. Mounted on a gridlike structure that uses a lattice of 230 small screens to project words and sentences as they are typed into computers, Listening Post is a collaboration by the New York-based sound artist Ben Rubin and Mark Hansen, a statistician and artist. Their inspiration was to ask themselves: “What would 100,000 people chatting online sound like?”

The duo’s work is curiously unsettling. For this viewer/ listener, the first response was a sense of wonder at the strangeness and beauty of the sights and sounds, which are choreographed into seven “movements” using text, voice and music. Then came a recognition of the intrinsic humour in many of the communications, followed by a slightly sinister discomfort at eavesdropping on thousands of people, all of whom are, in a way, trying to eavesdrop on each other.

If sound art has a beginning, it seems to lie with postwar avant-garde composers such as John Cage, the start of a line that follows through to Brian Eno’s ambient music, the sound collagists Christian Marclay and John Oswald - forefathers of the “mash-up” - and electronic composers such as the Japanese minimalist Ryoji Ikeda. Yet most of those are primarily musicians with artistic inclinations. Rubin, 43, who cites Cage and Marclay as influences, sees sound art as having more distant roots. “In the early 20th century, the Russian futurists were doing orchestras with noise-making machines,” he says. “And within experimental music, there is a tradition of composers doing spatial-installation projects that push far outside what you would consider music, towards what we now consider sound art.”

Exhibitions of sound art are relatively recent: Vienna, Berlin and Tokyo mounted shows in the 1990s, and Rome now has its own Sound Art Museum. Yet Britain’s first show, Sonic Boom, at the Hayward, was not until 2000.

Now, it seems, the genre is spreading further beyond its roots in experimental music. “It adds another dimension to the traditional art space,” Fabienne Nicholas, head of consulting at the Contemporary Art Society, observed at the recent Art Futures 2008 exhibition, where Paterson sold out her catalogue. “It might not necessarily give a physical presence, but it can give a strong environmental and emotional one. It’s particularly attractive in a confined space such as the lift at Birmingham’s Ikon Gallery, which has the sound of a choir whose voices rise and fall as the lift goes up and down.” For sound art, just now, the only way is up.

Encounters: Katie Paterson is at Modern Art Oxford from Wednesday; to hear the glacier melting, call 07757 001122. Heiner Goebbels: Stifter’s Dinge is at P3, NW1, April 15-27. Listening Post is at the Science Museum, SW7, until Feb 19, 2009

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