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Fifty years ago, Amar G. Bose ’51, the founder of Bose Corp., was a car nut. A geeky kind of car nut.

He wasn’t concerned with the obsessions of the day: horsepower, speed, and tail fins. He just wanted the smoothest ride possible.

Six years before the young Massachusetts Institute of Technology professor founded the company that’s now synonymous with high-end stereo speakers, he bought a 1958 Pontiac, which featured something called Ever-Level air suspension in which air bags replaced steel springs to absorb bumps.

It wasn’t good enough. He tinkered with the suspension for a decade, and then he bought a Citroen DS-19, a French oddball renowned for its radically streamlined shape and a pressurized fluid suspension with nitrogen shock absorbers. It once broke down on him at the Tanglewood music center, and he had to have it towed back to Boston.

Long after those cars were gone, the problem still gnawed at Bose: How can you design a suspension system that combines a smooth ride with superior handling?

Bose began working on the project in secret in 1980, and didn’t unveil the results until three years ago. His innovative system uses electromagnetic motors — powered by unique Bose electric power amplifiers and switches — to control the handling of the vehicle.

“In cars today, there’s always a compromise between softness over bumps and roll and pitch during maneuvering,” Bose, 78, said in a recent interview. “This system provides absolutely better handling than any sports car, and the most comfortable ride imaginable.”

The Bose suspension system will not be appearing in a showroom sometime soon. Having spent 27 years on the project, Bose isn’t about to start rushing the technology to market. But after years of refinements, and an investment of more than $100 million, Bose is ready to take the next step, and he plans to partner with a car manufacturer in the next year.

“There’s no question in my mind that it’s marketable,” said Bose. “But it requires a company that’s interested in more than styling and horsepower.”

There is surprising overlap between the physics of auto suspension and sound speakers. Both deal with waves and energy. The Bose suspension uses sensors to detect wheel motion, and proprietary electromagnetic motors to instantaneously adjust wheel position. The wheels move and absorb the bump, with almost none of the energy being transmitted to the body. To the driver, the effect is like riding a magic carpet.

The electromagnetic motors use switching amplifiers similar to ones Bose first developed at MIT in 1960. The trick was to make them fast — so they could respond in the nanoseconds as a car hits a bump at high speed — and to make them powerful, to counteract the tremendous forces at play within a car’s wheels.

Bose Corp. hasn’t yet let a journalist drive the 1995 Lexus LS400 fitted with its suspension system. Instead, it puts on a demonstration in the employee parking lot that is half solemn engineering display and half carnival side show.

First, a company driver puts an unmodified black Lexus through a course of bumps, a short slalom through cones, and an emergency stop. The car wobbles through the bumps. It heaves around the cones. And the front end dips precipitously during the short stop.

Then, the Bose-fitted car — it’s painted white — appears at the far end of the parking lot. It goes through the same paces. But the car’s body stays perfectly level. The wheels jump up and down wildly over the bumps, and the car moves serenely along, as if there were no connection between the wheels and the body.

For comparison, a Bose driver takes a Porsche Cayman through the same routine. If anything, the Porsche’s body bounces around the most, because its “sporty” suspension is so stiff. You can see the driver thrown violently about in his seat as the car traverses the bumps.

For a grand finale, Bose engineers play a trick. They lay a two-by-four across the lane, and say the Lexus with the Bose suspension will perform an emergency stop. The car approaches the obstacle at about 40 miles per hour, but it doesn’t slow down. Instead, the wheels jump nimbly over the obstacle. The Bose system has made a car fly.

It’s a crowd-pleaser, and it underscores the remarkable capabilities of the suspension system, even if it leaves an observer feeling manipulated. The well-oiled patter of the engineering staff makes clear they’ve performed this exercise hundreds of times before similar audiences.

“This is a fascinating technology,” said John Wolkonowicz, automotive analyst with Global Insight Inc., a forecasting and market research firm.

“This would work on a car that’s expensive enough, with a company that’s looking for ways to distinguish itself.”

Bose said that as he pondered the suspension problem, he thought the dynamics of vehicle behavior could be represented mathematically. He built a set of custom calculations to model the problem, and discovered that a solution would dramatically improve vehicle behavior. So he set up a secret internal team, dubbed it “Project Sound” to throw off internal speculation, and started building prototypes in the garage of one of his vice presidents who lived one town over from the company headquarters.

Engineers are still working to make the system smaller and less expensive. One obstacle is the price of neodymium, an iron ore mined largely in China that produces extraordinarily powerful magnets. “We need a lot of it,” said Bose. There’s also a powerful computer processor, but Bose is convinced the price for that unit will come down over time, as is typical with electronics.

Where will it debut? The Bose suspension system faces unique challenges. It’s a key component of a vehicle in an industry that is extremely suspicious of anything not developed internally. Moreover, the first car company to use it will be risking the success of a model — and possibly its reputation —on the performance of technology unproven in the market.

Industry analysts speculate the system could work well on a big image car — a top-of-the-line model that projects a “halo” effect on the rest of the model line. Wolkonowicz suggested a range-topping, $100,000 Cadillac sedan expected to debut in about four years.

Bose said a high-end Cadillac would be an ideal platform for his system, and acknowledges that General Motors gave Bose Corp. a big boost when it became the first car company to install its sound system (in a Cadillac) in 1981. But though the suspension system was a success when it was demonstrated to General Motors, he said, talks haven’t progressed.

“When we get ready, we’ll give them an opportunity,” he said.

Another possibility, according to analysts, is Audi, the luxury arm of Volkswagen AG, Europe’s largest automaker. Audi offers Bose sound systems on its models, and its large A8 luxury sedan has a reputation for employing advanced technology — it has an aluminum frame, unique among large cars.

“We’ve shown the system to all of the major manufacturers and Audi has not expressed much interest at this point,” said Bose.

And what about Citroen?

The French carmaker is now a division of Peugeot SA, but it still produces cars with the remarkable hydropneumatic suspension and enjoys a reputation for suspension wizardry.

Bose admits he hadn’t even thought of Citroen until a group of French reporters came to Framingham for a demonstration last year, and he doubts the company would take a risk with the new system.

Some of the strongest interest to date, Bose said, has come from automakers with more interest in sport utility vehicles than passenger cars.

What about letting a reporter drive the white Lexus?

Bose said that will have to wait, but he said it will be worth it.

“Boy, do you feel a difference,” he said. “There is a wow factor like you can’t believe.”