With tire roar, wind noise, and an engine rumbling in the background, you might think a car is a horrible environment to enjoy a high-end audio system. But back in the 1980s, Amar G. Bose—yes, that Bose—believed car interiors were better for accurate sound reproduction than, say, a living room.
In 1979 Bose approached General Motors about creating a sound system for a Cadillac Seville, developing a high-quality aural solution in just 90 days. GM soon approved production of the setup, which debuted in the ’83 Seville. The $895 option was a hefty expenditure for a car that cost less than $22,000, but it proved that an automaker and a sound company could collaborate to deliver a factory system with better audio quality than many thought possible.
Bose and GM have been partners ever since, and now Bose is rolling out the most ambitious system it has developed for the automaker, the all-new, 34-speaker Panaray, which debuts in the 2016 Cadillac CT6. Cadillac and Bose worked for the better part of four years to fully integrate Panaray into the CT6’s interior design.
Any major project at Bose’s Stow, Massachusetts, automotive lab starts with technicians modeling a sound system via computer before hacking apart an existing car and developing mounting brackets, speaker enclosures, wiring harnesses, and the like to create a demonstration audio system.
“I believed it would be possible to produce better sound in an automobile than in the home.”
-Amar G. Bose, Automobile, November 1998
Listening to the concept car is the most important part of pitching an audio system to a car company, says engineering support manager Bud MacLellan: “I can show you anything on paper, but you don’t know what that sounds like.”
The first concept Bose presented to Cadillac for the CT6 had 49 speakers. While that got toned down to “just” 34 for the production car, it’s still the most speakers Bose has ever installed in a car. (Its previous high, in the Maybach 57 and 62, was 21 speakers.)
Bose worked with Cadillac to get each speaker best situated, knowing the interior’s design limitations. Two “bass box” subwoofers are integrated into the front floor pan, and the 10-inch woofer in the parcel shelf is offset from center so it will fit around the battery pack in the coming plug-in hybrid.
Speakers and electronics must be as small and light as possible, part of the reason why the Panaray system has multiple smaller speakers rather than a few big ones. The speakers on the dashboard and in front of the rear seats, as well as the A-pillar speakers, angle in different directions, which provides a wraparound effect and minimizes localization, an unwelcome effect whereby listeners can hear which speaker a sound originates from.
In addition, car audio systems must tolerate far more abuse than ones meant for your living room. During testing, speakers must play for 24 hours while being sprayed with water and withstand 100-g impacts (to simulate hitting a pothole or slamming a door). Adhesives must hold up against UV rays that stream in through the windows. “The car is a pretty harsh environment,” says Bose Automotive’s Martin Dluzansky.
After all the physical parts were finished, engineers tuned the Panaray’s electronic signal processing. They used microphones to measure sound reproduction at each of the car’s seats, then programmed the amplifier to compensate for any deficiencies. Bose says its tuning process is so specific that it produces different maps for cars with cloth versus leather interiors and for when convertible tops are up or down.
The CT6’s 34 speakers meant a more involved fine-tuning process. Joe McCabe, Bose Automotive’s technical lead, recalls spending more than a month of 100-hour weeks programming the digital signal processing for the car before traveling to GM’s Detroit-Hamtramck factory to double-check that everything sounded as intended prior to production.
Despite all the innovation and engineering involved, at only $3,700 to start, the CT6’s Panaray system will be priced reasonably compared to some of its closest rivals.
“We were literally trying to get perfection in all four seats,” McCabe says. “When you’ve got 34 speakers and 19 equalizers, there’s a lot of complexity.”
Listening to It
While the CT6 wasn’t available for our full car-audio test, we had a chance to listen to a prototype at Bose’s office in Bloomfield Hills, Michigan. It’s a great experience, with pure and clear sound that wraps around the entire cabin. Deep bass has the booming, shake-the-seat feel of a movie theater; surround-sound effects seem to fly through the Cadillac’s cabin. We’ll have to get Sabin’s expert ears to listen to the Panaray system for an official verdict, but our initial impressions of the CT6’s system are very positive.