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Sonic Bits of Solid Gold

Tripath CEO Dr. Adya Tripathi holds some samples of the products his company makes, tiny semiconductor digital amplifiers. Photo by Associated Press.

Silicon Valley inventor offers digital sound revolution

By Brian Bergstein/AP

An invisible hand seems to be confidently plucking guitar strings a few feet away. Bass thumps heavily and unmistakably, but without distorting vibrations. The room feels ringed with drums.

The most amazing thing about this high-fidelity experience: It isn’t coming from a top-tier stereo system with a five-figure cost. It’s being blasted through the speakers of a humble personal computer.

The advance comes from a little chip produced by Tripath Technology Inc., a 150-employee company in Santa Clara, Calif. It was founded in 1995 by Adya S. Tripathi, a 48-year-old engineer from the holy city of Varanasi, India, who dreams of improving the world’s relationship with sound.

Tripathi believes he can bring about inexpensive home theater systems, more powerful cell phones, better Internet access and new hybrids of electronics — like set-top cable TV boxes with a high-end sound system already included. And after raising the quality of the sounds we hear, he also believes he can drown them out, by using his technology to power noise-reduction devices.

“With our technology, many things that were not possible are now possible,” he said.

Tripathi has had little trouble convincing others to hear things his way. Before taking the company public last year, Tripathi secured $50 million in funding from such high-tech heavyweights as Cisco Systems Inc., Intel Corp. and Texas Instruments Inc.

Tripathi’s breakthrough was to vastly improve the performance of amplifiers, which perform a key function in most electronic devices. Amplifiers accept an incoming signal and boost it out — through a stereo speaker, for example. The problem is that inexpensive amplifiers tend to distort the signal, and expensive ones with high fidelity are clunky and inefficient, sucking power and creating large amounts of heat.

A solution struck Tripathi while he tried to sleep in his dorm room in India one night more than 25 years ago. He figured out a way to make the amplifier work digitally — converting its signals into a series of ones and zeroes that are processed at regular intervals. Traditional analog technology involves processing signals continuously.

Tripathi moved to the United States in 1979 and worked at IBM Corp., Hewlett-Packard Co. and National Semiconductor Corp., waiting for technological advances to make his dream cost-effective.

Now his patented system, called digital power processing, is behind the circuitry in amplifiers that are a fraction of the size of their predecessors, use far less power and create much less heat. The key ingredient, the power-processing chip, fits on a finger and sells for as little as $4. Rather than coming as a bulky and costly separate attachment, the digital amps fit inside space-deprived devices like PCs, which consumers are increasingly using to hear music, play games and watch videos.

Tripath’s amps have cropped up in new Blaupunkt car stereos, Apple Computer Inc.’s Power Mac G4 Cubes, high-end Sony Vaio computers and some late-model Dell PCs. In addition, Belgian networking company Alcatel is partnering with Tripath in hopes of improving the performance of digital subscriber lines for high-speed Internet access.

Apple found Tripath amplifiers were nearly three times as energy-efficient as comparable models — an important factor for the Cube’s design, which has no fan — and had very high sound quality, said Mike Culbert, Apple’s director of system architecture.

“They’re miles ahead of what’s out there now,” Culbert said.

Tripath had $9 million in revenue last year and expects sales of more than $30 million this year. Analysts don’t expect Tripath to be profitable until the fourth quarter of 2002, however.

“Clearly they’ve had a breakthrough, and no one appears to be close at this time,” said Shekhar Wadekar, a research analyst with Dain Rauscher Wessels, which helped underwrite Tripath’s initial public offering. “The company’s position gets better day by day as they win customer acceptance.”

Still, how well Tripath’s chips will work in low-power devices like cell phones and handheld computers remains to be seen.

One company that hopes to mine that market is rival National Semiconductor Corp. Ken Boyce, an audio products marketing manager, would not comment on the specifics of Tripath’s technology. But he pointed out that cell phones and handhelds are sensitive to interference that can be created by some methods in digital amplifier technology.

Tripathi is already looking further into the digital future. He theorizes that his technology could be used to shush car engines, blenders or noisy children by emitting sound waves digitally tailored to interfere with each annoying sound.

Though noise-reduction devices are years away, talking up their potential is one of his passions. Tripathi, who owns about 36 percent of the company and is president, chief executive and chairman, half-jokingly admits that sometimes he needs to be reminded to focus on the business at hand.

“Do what you like, and where your heart belongs, and money, wealth, fame, everything follows you,” he said. “Because if you chase all those things, you know, they go away from you.”