Continental has designed a unique in-car sound system that does away with speakers altogether. It uses actuators to create sound by vibrating surfaces within the car, working on the same principle as stringed instruments such as the violin.
The actuators consist of a magnet and a vibrating coil, which convert electrical signals into motion. Using a special bonding technology, the sound waves are transferred into a panel in the car - this could be the dashboard or inside of the door. The panel radiates the soundwaves, effectively turning every interior surface into a speaker.
The system is called AC2ated. Not only is it extremely cool, it's also cheaper for car manufacturers, as they don't have to worry about expensive speaker components. Plus it's lighter than a traditional speaker set-up, meaning it will help the car be more fuel efficient.
According to Continental, different parts of the car are better suited to different frequencies. The A-pillar suits high frequencies, while the door panels have the right properties for generating medium frequencies. The roof panels and rear shelf are better for low frequencies and could act as a subwoofer.
Continental has installed a prototype of the system in a Mercedes C-Class, though it says mass production is still several years off.