Pressing the Mute Button on Our Daily Soundtrack

Back in the prehistoric 1970s, one of life’s little pleasures was the ability to slam down a telephone on annoying callers. Now, thanks to the rise of cordless phones, the best you can do is fiercely poke the off button -- or, if money is no object, throw the receiver into a wall.

The slamming phone, like dozens of once-familiar sounds, is headed for extinction. As technology advances, more and more noises -- the pop of flashbulbs, the gurgle of coffee percolators, the clatter of home-movie projectors -- are fading into oblivion.

While audio junkies scramble to preserve samples for future generations, psychologists debate the consequences of this noise exodus. Some foresee a sonic revolution -- one that could launch a surprising wave of silence and perhaps force Hollywood studios to rethink the way they tell stories.

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Inside a bombproof vault a few blocks from the White House, Dan Sheehy is surrounded by audio ghosts: the clicketyclack of typewriters, the tumble of glass bottles inside a soda machine, a 1960s-era telephone ring.

Here, sonic blasts from the past are entombed in a hodgepodge of vinyl records, compact discs and reel-to-reel tapes. “We are a museum of sound,” said Sheehy, whose job is to preserve America’s acoustic heritage for an obscure branch of the Smithsonian Institution.

Sounds are like smells, he says. They can transport the listener to another time and place. The buzz of an airplane propeller sends Sheehy’s mind back to hot afternoons in 1950s Bakersfield, playing in the yard while aircraft sputtered overhead. “The sound immediately triggers memories of time and temperature,” he said.

A handful of obsolete noises are so ingrained in our consciousness that filmmakers and advertisers still use them to evoke audience reactions. In the 2002 movie “Undercover Brother,” for instance, a phonograph needle scraping across a vinyl record signaled an abrupt halt to the action.

The emotional power of vintage sounds might explain the popularity of cellphone ring tones that mimic rotary telephone bells. “It’s one of the biggest ring tones we sell,” said Tom Valentino, president of Valentino Production Music, the nation’s oldest sound-effects warehouse. In a similar vein, slot machines that pay out vouchers instead of cash often play a recording of cascading coins because research found customers missed the jackpot noise.

Valentino has heard a lot of sounds come and go over the years. In 1932, his father got into the business by recording a milk wagon traveling down a New York street, the first of what is now a library of more than 50,000 sound effects. (The elder Valentino also worked with Orson Welles on “War of the Worlds” and once captured the chug of a steam train running full tilt by greasing the railroad tracks at Grand Central Station so the locomotive couldn’t move.)

Many of the company’s recordings are now historical relics. A slamming car door from the 1960s, for example, sounds more metallic than today’s rubberized thunk.

Sounds are always mutating, Valentino said, but the pace accelerated after the advent of computerization. Electronic cash registers eliminated the ka-ching of their ancestors; digital cameras erased the traditional shutter-click and advancing-film noises of their predecessors; PowerPoint presentations chased away the clunks and whirs of slide projectors.

The lifespan of sounds seems to be shrinking, Valentino said: “We sent our engineers to Ft. Bragg 25 years ago to record military tanks. All those sounds are now totally historical.”

So are old pinball machines, car horns and pull-chain toilet flushes. Even the scratch of chalk on a blackboard is being exiled by the squeak of markers on dry-erase boards.

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A Subtle Shift

For most of history, the soundscape rarely changed.

“From the birth of man until the late 1800s, the predominant sounds human beings heard arose from nature,” said Rex Julian Beaber, a psychologist and attorney in Century City.

The Industrial Revolution upended all that, unleashing a cacophony of man-made noise. Today, another sonic revolution is underway. Although many observers fear the planet is about to become louder (check your local Dolby surround-sound cinema), Beaber foresees a wave of silence. Modern technologies are turning down the volume of our mechanized society, he says.

So far, the differences are subtle, such as the click of a TV channel knob being muzzled by electronic remote controls. But eventually, when the roar of the internal combustion engine is muted by the whir of electric or fuel-cell motors, “we will return to the world from which we came, one in which the big sounds we hear are from nature,” Beaber predicts.

Such a transformation would be stunning, said Diana Deutsch, a UC San Diego psychology professor who studies the perception of sound.

“If you go to the mountains today, the silence is so remarkable you just listen to it. We evolved under that. Our ears have not evolved to handle the noises we’re bombarded with daily.... If indeed we were able to return to a truly quieter world -- free from the noise of jet engines, bulldozers, pneumatic drills and the like -- I believe it would be a blessing.”

But it could also be a bit unsettling.

Although the invention of a digital leaf blower probably wouldn’t upset anybody, other changes in the sonic tapestry might create a sense of loss. That’s where Folkways Records enters the picture. In 1948, Moses Asch, an electronic engineer who spent the early part of his career installing public-address systems, set out to immortalize “anything that is sound.”

Most of his catalog was music (he was the first to sign Woody Guthrie and Leadbelly), but he also issued recordings of elevators, jackhammers, mosquitoes, cocktail parties, calliopes and an acetylene torch cutting through an automobile engine, to name a few.

Before his death in 1986, Asch agreed to donate his archive to the Smithsonian Institution -- on the condition that everything would permanently stay in print and be available for purchase.

“Do you delete the letter Q from the alphabet just because you don’t use it as much as the others?” he reasoned.

Asch’s legacy is mind-boggling. “If I did nothing but listen to the collection 40 hours a week, it would take two years to hear everything,” Folkways director Sheehy said.

At the label’s website (www.folkways.si.edu), visitors can buy or sample hundreds of acoustic oddities, from “Supervised Surgical Operation on a Small Boy With a Cyst in His Neck” to “Sonoran Spadefoot Toad When Seized by a Hognosed Snake.”

(At least one recording might be fake. A 1950 disc, “Sounds of the Rain Forest,” is rumored to have been taped in a New York shower.)

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Tuned In, Tuned Out

Why do some antique sounds, such as steam locomotive whistles, remain widely missed while others go to the graveyard barely noticed?

Part of it is personal taste. “Noise for one person is hi-fi for someone else,” said Steven Feld, a professor of anthropology and music at the University of New Mexico in Santa Fe.

Culture also plays a role.

Author Nick Harrison illustrates the point in “Promises to Keep,” a book of spiritual meditations, with a story about a Native American and a native New Yorker walking through Manhattan.

When the American Indian says he hears a cricket amid the clamor of the city, the New Yorker snorts, “You’re crazy.”

But the Native American listens again, then crosses the street, digs into a planter and finds the insect. When the New Yorker expresses amazement, the Indian replies, “My ears are no different from yours. It simply depends on what you are listening to. Here, let me show you.”

The American Indian then drops a fistful of coins onto the sidewalk and every head within a block turns around.

Although the story might be apocryphal, the point about people listening differently is accurate, Beaber said: “A lot of hearing is learned.”

In the U.S., movies and TV have trained the human ear to think some studio-created sounds are more “real” than the originals. In winter scenes, for example, the crunch of someone walking across 50 pounds of cornstarch seems more authentic than the muffled noise of real snow, Valentino says.

However, the ability of Hollywood sound engineers to conjure audience emotion will fade in the near future, Beaber predicts.

Right now, sounds such as creaking doors help create drama on the screen, he said. But the day is coming when door technology, which hasn’t changed in centuries, will switch to an airtight, silent mechanism like something out of “Star Trek,” he said.

“Once people have lived in a world where doors don’t creak,” that sound effect will lose its dramatic punch, Beaber said.

It’s happening with shoes. Although the clip-clop of leather soles against sidewalks is still a movie staple, in real life the sound of walking has largely been anesthetized by rubber soles.

Eventually, Hollywood will have to rely more on visual cues than audio effects, Beaber said.

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Select Significance

Nostalgia for expired noises is similar to not noticing the hum of a refrigerator until it shuts off. “You only remember the sound in retrospect,” said Deutsch, the UC San Diego professor. And then you quickly forget about it again.

When compact disc players first hit the market, music lovers initially grew hyper-aware of all the cracks and pops on their old phonograph records, she noted. Some people even missed the scratches, comparing the background noise to the crackle of a fire.

In the long run, every audio dinosaur will suffer the same fate, Beaber said. Air raid sirens, stock tickers, Pong video games -- each one carries significance for the generation that grew up with it, but once that generation dies, the sound becomes lifeless.

Imagine a newspaper story in the 1920s about vanishing noises, Beaber said. The prime example would be the clop of horse hoofs on pavement.

“People would be talking about how the world just wouldn’t be the same without that sound,” he said.

But flash forward to 2004. “Do we find ourselves longing for the sound of those hoofs now? Of course not,” Beaber said. “Humans adapt and move on.”

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Becoming disconnected

The list of dead and dying sounds keeps growing.

One of the chief habitats for endangered audio species is the telephone. The busy signal has been curtailed by call-waiting. The clink of coins in pay phones is being overtaken by credit cards. And the soothing whoosh of rotary dialing has been replaced by the tones of push buttons.

Even the relatively young screech of telephone modems is being hustled out of earshot by DSL and cable computer connections.

Modernization has also taken a toll on other sonic standbys, including:

The wavy electronic frequency noise heard when changing stations on a manually tuned radio (virtually eliminated by digital tuners).

* The hum of adding machines (deep-sixed by the gentle tap-tap of calculator keys).

* The telegraph.

* The ticking and winding of watches (succumbing to digital and electronic timepieces).

* The rat-a-tat of daisy-wheel printers (courtesy of inkjets and lasers).

* The click and clink of pull-chain light switches (extinguished by mercury switches).

Roy Rivenburg, Times staff writer