Audi Sound Concept - Q7 Audio Racing

Ever since the automobile first received a sound system back in 1930s, car manufacturers have become more and more interested in offering an improved audio experience for their customers. Modern times have brought ultra-sophisticated sound systems into our cars, with the world’s top developers collaborating with car makers to achieve the aforementioned goal.

The latest development in the field comes from the German premium automaker Audi, which has worked with his traditional partners Bang & Olufsen and Bose, as well as with the Frauhofner Institute for Digital Media to develop a complex audio system that would deliver the ultimate spatialization experience. The companies have created a demonstrator system that includes 62 speakers mounted in an Audi Q7. But let’s get to the details.

Dubbed the Audi Sound Concept, the system uses a physical principle called wave field synthesis, which states that the front of any individual wave also represents a superposition of individual waves. In hi-fi language, this means that a sound wave can be recreated by multiple small sound sources located closely adjacent to one another along the wave front.

The principle was first applied during the 80s in the Netherlands and can be experienced today in a movie theater in Ilmenau, in the German state of Thuringia. The site uses 192 individual speakers, with each one of them controlled by a computer, being actuated at the precise moment when the virtual wave front passes through its point space. Some signals are delayed by milliseconds. The result is stunning, offering a bewildering sound experience.

One of the top developers in the field of wave field synthesis is the Frauhofner Institute for Digital Media Technology (IDMT) in Ilmenau, which became an Audi partner five years ago, when the Audi Sound Concept was started.

The project initiated by the two sides has evolved into the Q7 experimental sound vehicle, which is housed at the Institute. The largest component of the system is a powerful amplifier that takes up the majority of the full size SUV’s luggage space and is connected to three PCs. The vehicle has received 62 speakers (five woofers, five tweeters and 52 mid-range speakers) that are placed in the dashboard beneath the windshield, in the roof pillars and in the doors. Each door sill houses five units, with Audi making cutouts in the sheet metal, fabricating new bezels and lowering the interior door handles to accommodate the hardware.

The system also has its dedicated demo soundtrack that includes a multitude of emotion-creating passages, such as lion roars and engine sounds, which are mixed to offer the multi-dimension effect. The material comprises up to 32 tracks, with each one of them including specific spatial information. Audi claims that the are no corresponding audio products on the market, adding that method is only used by a few film studios for their creations.

However, wave field synthesis doesn’t necessarily require custom material to offer an audio show. It can also offer a totally new face for standard stereo signals, changing the way in which there are perceived by the user. One example that perfectly illustrates the technology’s capabilities is the generating of a sound that seems to be coming from outside the Q7, with this impression remaining the same regardless of the listener’s position in the car. The application not only offers the impression of an external sound, but also make it seem like the sound source is far away from the vehicle.

In addition to that, the system can add any kind of spatial impression computationally, not as a sound effect, but as a mathematically precise simulation.

The system has managed to deliver a quality experience during all the experiments, offering sparkling trebles, clear mid-range and dry bass. The developers have worked to make the system reproduce even the slightest sounds, such as the buzz generated when the guitarist’s fingers hits the strings.

Audi’s goal with the Sound Concept is to demonstrate what is technically feasible, to explore the limits of current technological development. The company compares the experiment with racing. To be more precise, the automotive maker claims that many of the elements which were first tried out with the bespoke Q7 will make it into its future production vehicles.