Developing and creating car sound systems is the most visible and well-known part of Bose’s business in the automotive world. The American audio specialist can boast of numerous and varied collaborations: in Nissan / Renault, Mazda, Porsche, Opel or even Hyundai, Bose’s options are found in both city cars and decidedly sporty models. . As you’ve probably seen in our recent dossier on acoustic research at Renault, sound reproduction isn’t the only problem car manufacturers have when it comes to designing a vehicle. And on these other topics, Bose also offers the fruit of his research in signal processing and active noise reduction.
Route Noice Control: A system for eliminating road noise
Car manufacturers and specialist audio brands have already studied the management of perceived noise on board using acoustic / electronic solutions. At Bose, controlling the noise generated by the engine of a thermal vehicle has been the task of two of its own technologies for more than 10 years, Engine Harmonic Cancellation and Engine Harmonic Enhancement: the timbre of the latter is previously analyzed during the design of vehicle and then in real time while driving in order to reduce the perceived noise (signal emitted in phase opposition by the vehicle speakers) or vice versa to optimize / modify it according to the specifications defined by the car manufacturer.
The increase in power of the electric vehicle has posed a new problem of noise, this time at the bearing level, much more noticeable as it is no longer masked by the internal combustion engine. Bose is once again finding an answer to this problem through electronics and Road Noise Control. This system no longer works directly at very precise and very low frequencies, but in a much wider band between 40 and 400 Hz. Obviously determined to outperform its few competitors and forge as many partnerships as possible, Bose presents its system as very sensitive and sensitive. adaptable.
An accelerometer is placed near each wheel to measure real-time vibration changes. Then, the principle of operation remains the same as for the reduction of engine noise, again with the use of the vehicle’s reproduction system, and a network of microphones is placed in the passenger compartment to ensure a good system performance. In terms of adaptability, Bose says its algorithm is calibrated to anticipate some evolution over time, among other things based on the level of tire wear. We were able to perform a brief test in a situation on board a demonstration vehicle (with the possibility of activating or not the RNC system as desired, which is not absolutely the goal in a production vehicle intended for the general public ): the result is certainly not impressive, but we have nevertheless detected a certain efficiency in removing the noise generated on a fairly old paved road, especially when passing over certain defects in the road that become virtually “ transparent ”.
In the future, Bose wants to develop its device to address an even wider range of frequencies and higher frequencies, in particular to counteract the noise caused by wind at higher speeds – a challenge that promises to be especially arduous when you know you already do. does. represents a small challenge in itself for Bluetooth headsets and headphones with active noise reduction, where the volume to be isolated is infinitely less important and where there is no sweet spot problem.
Create different sound bubbles in your car with SeatCentric
Bose also did a very quick demonstration of SeatCentric, a Bose technology that aims to create a personalized sound experience for each booth position. In principle, the vehicle, equipped with both its “conventional” sound system and pairs of UltraNearField speakers housed in each seat (either on the headrest or at the top of the backrest), is capable of broadcasting different content, or simply to manage your individual listening volume. A system that can be useful for making calls without disturbing or sharing content with passengers, or for enjoying music while annoying those who want to rest as little as possible on board, for example.
The demonstration allowed us, above all, to observe the individual management of the volume, which is more practical than necessary for the reproduction of sound, and a situation of listening to music from the call of the driver / passenger which was quite convincing: with a reasonable level of listening, it was especially difficult to follow the conversation on the driver’s side, and on the other hand, the driver’s conversation was clear and uncontaminated by the music in progress. SeatCentric technology, still in development, aims to give users a truly personalized listening experience, and it is possible that we will be able to see it in action for years to come.
Bose is also getting into “3D audio” with its 3DX technology
Like Bang & Olufsen with audio, Arkamys with Renault or even Sennheiser, Bose also wants to keep up to date with sound features and will therefore offer an audio system capable of delivering a 3D sound experience. Simply called 3DX, this technology is based on a system consisting of a set of “classic” speakers (housed in commonly used cavities), UltraNearField speakers to enhance the presence of sound and improve the perception of the scene, and several speakers on the top. part of the cabin to recreate a feeling of sound elevation.
Everything is governed by the signal processing algorithms developed by Bose (including SurroundStage which is already used in certain models) which, for the time being, only act by applying an upmix to any stereo source. Bose says it will closely monitor the development of 3D audio formats in the music industry to optimize its technology, already cut for exercise. The future will tell if the American manufacturer will achieve its goals …