LISTENING PLEASURE

Connected, streaming and with speakers aplenty, your car is a mobile media room

When Bose fitted four modest speakers to the 1983 Cadillac Seville, the innovative American audio company could not have anticipated the impact it would have on how we bop along in the car. Only a decade earlier, an FM radio with a pair of speakers was a relatively luxurious addition to a car.

Suddenly there was a respected home audio company plumping up an automotive interior with speakers and amplified sound.

It was a hit, kickstarting a revolution in car audio — spawning boom boxes on wheels with a proliferation of speakers, amplifiers and subwoofers.

At the top end there’s serious punch. The coming Bentley Continental Flying Spur has an optional 21-speaker set-up with two bass transducers (effectively shakers beneath the seat to ensure you feel the bass). The Lexus LS has 23 speakers.

But it’s not just luxury cars. Toyota, Mazda, Nissan, Subaru, Hyundai, Kia, Holden, Ford, Mitsubishi and Volkswagen fit top brand audio on their more expensive models.

Mazda Australia marketing director Alastair Doak says connectivity and infotainment are crucial in luring buyers.

“The quality of the sound system has a significant part to play and the expectation of consumers these days is much higher,” he says.

That’s why the MX-5 roadster includes speakers in the driver’s headrest.

It’s also why the latest Mazda3 gets a revamped audio. This will flow through to coming models, including the CX-30 due next month.

Mazda worked to separate the bass and midto-high range sounds to better position speakers in relation to human ears.

“In a listening room,” says Yoshihiro Teshima, from Mazda’s electrical and electronics performance development department, “the speakers are aimed directly at you and you can listen while seated in the middle.”

In cars, however, most occupants sit closer to one set of speakers.

Teshima explains: “If mid to high-range speakers are mounted on the top of the dashboard … you are basically listening to music reflected off the windscreen.

“These reflections … affect audio quality and clarity, making it difficult for listeners to get the sense of where an instrument or singer is on the sound stage.”

Some Mazda3s get a 12-speaker Bose set-up. Even for its basic eight-speaker layout, Mazda chose to fit the higher frequency speakers in the tops of the doors.

It employs a “priority mode” for the driver so that, Teshima says, “the sounds from the left and right speakers arrive at the driver’s ears at the same time and the same sound pressure level”.

Bass speakers, now moved from the doors to the dash, produce “powerful and tight bass with no buzzing”.

Doak says: “It’s indicative of the expectation of consumers that we went to great lengths to improve our standard system on our new-gen product.”

No surprise that premium audio is a priority for BMW and, says 7 and 8-Series product planner Howard Lam, this led to the maker fitting the latest Bowers & Wilkins “Diamond Surround Sound System”, notable for its diamond and kevlar speakers.

Locating the best spots for speakers in cars creates challenges for engineers but there are also advantages compared with home audio. Rooms and furniture can affect the quality of sound — but for each car model, the interior is identical, so planning the audio layout is easier.

Car audio was once an afterthought, added with the tick on the options list, but now it is integral to the design of the car.