Sound is special – HiFi in the car: The developments are spectacular

Ever higher wattage, ever fatter subwoofers, ever more speakers? The future of sound in the car looks different than the previous orgy of materials. Suppliers, manufacturers and software developers are working on completely new sound dimensions – but they are also forced to do so.

Greg Sikora hates loose change. Candy wrappers get on his nerves. Or packs of tissues. Jingling, crackling, rustling from somewhere in the depths of the car shelves: The noises of such cent articles can devalue his work of many weeks. Because “for me, they destroy the flawless sound that we have worked endlessly on.” A nightmare for the head of the Acoustic Systems Engineering Department of the world’s largest car hi-fi manufacturer Harman. Sikora is in the halls of Harman’s Munich Car Lab , which includes brands such as JBL, Infinity, Bowers & Wilkins, Bang & Olufsen and Marck Levinson. And in front of him is a prototype of a new Aston Martin, in which his technicians are looking for the ideal position for the deep bass from the subwoofer. Not an easy undertaking in the confines of a sports car. After all, it’s pumped full of technology and engine power anyway – and in the best place under the seats, the space in such a raging flounder is too small for the thickest loudspeaker with its need for resonance space. “Thank God it can also be installed in other places, such as the trunk, because the human ear can hardly localize its noise,” says Sikora. The only thing you can’t hear is the rustling of banknotes… However, this doesn’t apply at all to the other sound waves – here people can hear exactly where the sound is coming from. And that is why there is a trend towards more and more loudspeakers in cars. Even basic equipment often offers half a dozen sound transmitters, which can be upgraded even in small cars with a few hundred euros extra from the factory. And BMW, Lexus or Mercedes customers sometimes shell out several thousand euros to bring hundreds of watts, loudspeaker batteries everywhere and last but not least glorious brand logos of audiophile tradition into the car. In the Aston, Bentley, Rolls or Maybach it’s already in the dimensions of a small car price. Instead, Hifidelity thunders from a Burmester system in concert hall quality and three-dimensional surround sound like in a high-tech cinema – over 21 high-performance loudspeakers including additional tones from two roof islands between the rear seats and with 1,480 watts, i.e. 1.48 kilowatts. Or should we say something more than 1 hp? There is space for a concert hall in the smallest car. Technologies that Sikora trims its systems in the car for also come from the cinema and concert hall: “Thanks to home cinema systems, listening habits are now so highly developed,” says the developer. That’s why the teams measure the sound development in the world’s most famous concert halls, such as the Wiener Musikverein – and recreate the sound experience using the high-quality systems in the car. “Especially in times of social distancing, live experiences can be streamed securely with high transmission rates,” says Sikora. Some car owners then no longer want to drive at all, but only want to experience great opera from the Arena di Verona in the parking lot. Together with the tenor Andrea Bocelli and his favorite opera house in Pisa, JBL has developed such a system for the Fiat 500. Formats originally designed for the cinema, such as Dolby Atmos, are also changing on-board listening. The Dolby makers, together with the German multimedia specialist Cinemo, have developed a system for cars in which 21 front, rear, side and height speakers and eight structure-borne sound converters in the seats not only allow the feeling of music to float freely in the room, but also the signals and warnings that are particularly relevant for people behind the wheel. Professional musician Christopher von Deylen enthused when presenting the system: “Compared to Dolby Atmos Music, stereo sounds like mono.” A lot of watts, a lot of kilograms However, the “wish-you-watt” orgies bring two big problems: Top systems can weigh a hundredweight and consume energy accordingly. Not exactly pioneering when working on sustainable mobility. Developer Sikora also relies on smaller loudspeakers that concentrate on the spectrum that is actually audible to the human ear. Top sound without loudspeakers Sennheiser and Continental approach the battle for sound in a radically different way: they want to produce 3D sound entirely without loudspeakers. For this purpose, Sennheiser has integrated its Ambeo 3D audio technology into Continental’s Ac2ated sound system. Door linings or body parts with targeted vibrations themselves take over the sound generation. The installation space and weight of a sound system should be reduced by up to 90 percent. The partners want to develop a series version in the next few months. However, developer Sikora does not really believe in the end of the loudspeaker: “The idea has been around for a long time. But firstly, the car manufacturers want to avoid vibrations in their body parts, secondly, nobody knows what the sound will be like after a few years of use – and thirdly, the requirements of the future require precise sound reinforcement for the ears of the individual passenger.” The trend is going therefore more to the sound from the headrest.Headrests like headphonesBose, for example, already uses such headphone-like systems at Nissan, and Hi-Fi competitor Meridian in the Range Rover. The sound can thus always be played out in the ideal relationship to the head – important, for example, when the passenger puts his seat in a lying position or turns the entire seat in an autonomously driving vehicle towards the second row. There is also a trend towards hearing islands. Already, many rear-seat passengers may prefer to enjoy a movie or video game on their front-seat screens. And with the advent of separate screens for the front passenger, they may also want to skype – and not be distracted by the music or navigation announcements from the person behind the wheel. After all, in the audio experience of the future, that can be almost as annoying as small change in the glove compartment. (SPX)
source site-13