The computer industry has made noise about the benefits of faster and smaller microprocessors, but a new chip designed specifically for hearing aids promises to let some patients hear it.

Several Valley hearing specialists are lauding what they say is the world's first all-digital, in-canal hearing aid. Senso, which was developed by Netherlands-based Widex Hearing Instruments, makes more than 40 million calculations per second, rivaling Intel's Pentium chip. The device samples and processes incoming sound at the rate of 32,000 times per second, adjusting levels instantaneously.

It offers hearing assistance programed to a patient's specific needs, automatically adjusting volume, high and low frequencies, feedback and background noise.

Although digital hearing aids, including older versions of Senso, have existed for several years, the newest device is small enough to fit completely inside the ear canal, making it appealing to those who have resisted wearing visible artifices because of the way they look.

"Vanity has always been the No. 1 reason people resist or put off getting fitted for hearing aids, especially those employed in the business world," said Cathy Kurth, a clinical hearing specialist in Scottsdale. Kurth added that while the in-canal aid isn't right for everyone, the digital technology in most cases provides far superior quality to even relatively new analog systems at about the same price.

The newest Senso runs about $2,500, while top-of-the-line analog systems typically sell for about $2,000.

Widex spent 10 years and more than $10 million developing the microprocessor, designed specifically for analyzing and modifying those sound waves.

And according to Kurth, the effort has paid off.

Kurth said comparing analog hearing aids with their digital counterparts is like stacking up a vinyl record against compact discs.

"With analog hearing aids, you'll often have circuit noise, noise of the microphone, hissing noises and distortion," she said. "With digital, you can have much cleaner sound with little distortion."

One of the most noticeable benefits of the digital technology is its performance in noisy environments, a condition that can reveal weaknesses in even the most expensive analog systems.

Kurth said most most of her patients that have used the devices are sold on them. She added that the in-canal unit will prove especially useful in the corporate world, where first impressions can have a significant influence in his business dealings. While hearing aids have become much smaller over the years, the in-canal Senso is the first to boast near-invisibility.

According to Bob Scharber, a hearing specialist at East Valley Hearing Center, other patients have expressed similar feelings. "When you consider the issues people consistently ask about - cosmetic benefits, volume, feedback and background noise control - the digital CIC pretty much covers it all," he said.

Even so, proponents acknowledge that the devices aren't for everyone. The benefits will vary depending on the patient's specific hearing loss, and some will experience no improvement.