The cacophony of city noises sounds like music to his ears.

David Bradshaw recently spent half an hour wearing headphones under a bridge at the Port of Long Beach. Later, he dragged his digital tape recorder to a railroad crossing, then stood a few yards from an oil refinery until an attendant asked him to leave.

“We can’t allow anything like this to go on,” said the Huntway Refinery Co. worker.

While some artists pass through life with open eyes, Bradshaw, 31, also travels with his ears wide open. A collector of tones, he has recorded hundreds of them in the last seven years. His quest is to make art of the random sounds that assault us daily. More specifically, he hopes to arrange them in ways that are music to our ears.

Although he has not yet earned any money from his unusual avocation, the Long Beach Museum of Art--where Bradshaw prepares exhibits for a living--recently thought enough of one of his compositions to make it the theme song of its weekly “Arts Review” program on cable television. And for the last year and a half, Bradshaw has been composing and recording a number of pieces which he hopes to meld into his first album.

While the use of natural ambient sounds by recording artists is not uncommon, Bradshaw--who has had no formal musical training--believes his art is unusual in that it begins with sounds, which then suggest compositions.

“I’m inspired by sounds,” he said. “I approach it not from a musical perspective, but on a conceptual basis; I’m interested in where the sounds come from. What I do is load a bunch of them in that I think will sound good together. I start with the rhythm, then add the melody.”

Using specialized digital equipment in conjunction with an Apple MacIntosh home computer, Bradshaw isolates and mixes his auditory samples until he achieves a combination he finds pleasing. Occasionally he uses live musicians to fill in gaps, but more often the result is a highly individualized--and sometimes hauntingly familiar--musical medley consisting almost entirely of environmental sounds.

The song featured on cable television, for instance, includes the grinding start-up of a motor-driven observatory turret in Arizona. Another composition, entitled “Brouhaha,” features the barely recognizable strains of a chair squeaking, water hitting a hot frying pan, a chain being dragged across a floor and a cigarette lighter being flicked open.

Other sounds Bradshaw has recorded include that of car horns, peacocks, the drainage system of a cruise ship pool, boat masts clanging together at night, sounds made by people’s mouths, music boxes, conch shells and the hum of high-tension wires twanging in the mountains.

“Right now I’m in the market for car noises and workshop noises,” said Bradshaw, who has traveled all over Southern California in pursuit of new and stimulating sounds. “I’ve been trying to record the sound of a car with squeaking brakes, and I haven’t been able to find a good one yet.”

Trained as a filmmaker and photographer, Bradshaw says he first got interested in sounds as a result of his experiences while recording the sound track for a film he was working on. “I listened for years thinking that if I could only record (the sounds I heard), it would be music,” he recalled.

During his recent excursion to the port, in fact, music was what he seemed to be hearing.

“That’s very good,” he said at the refinery. “There’s an incredibly high-pitched squeal between the stroking sounds.”

Vibrations at the other sites pleased him as well. “Various rattles and the bell,” was his description of what he had heard of the passing train. And under the Schuyler Helm Bridge amid the deafening rhythmic ka-thump of cars passing overhead, he said: “There’s a certain kind of rattling plate sound I’ve been trying to get. I got a good one today.”

Recording ambient sounds can be challenging. After several minutes under the bridge, for instance, Bradshaw decided that the sound could be recorded better late at night when it was less likely to be diluted by extraneous noise. Later, climbing hurriedly out of his car to record the roar of the passing train, he was not quite quick enough to catch the single blast of its horn. Finally when the refinery attendant refused to cooperate with the young man’s artistic intentions, Bradshaw decided to call it a day.

So it was back to his downtown studio loft, there to carefully evaluate the session’s recordings and perhaps dream of recordings yet to be made. Somewhere he has a list of sounds as-yet unrecorded, including cats purring, stomachs gurgling, plumbing groaning and foghorns blowing.

“I’ve often thought,” Bradshaw said, “that I’d like to mount a couple of microphones on top of the car. That way I could just stop wherever I am, cut the engine and record the sounds.”