Flat Flexible Loudspeaker may make walls, seats talk

By Leslie Katz on 02 April 2009, 10:24am

Warwick Audio Technologies has created speakers that are less than a quarter of a millimetre thick and can be hung on walls like pictures to make announcements in places such as passenger terminals.

Engineers at the company, a spin-off from the University of Warwick, say the Flat Flexible Loudspeaker is so slim and flexible that it could even be concealed inside ceiling tiles or car interiors, conceivably leading to talking roofs, wallpaper and car seats.

According to the engineers, the speakers are ideal for public spaces because they deliver planar directional sound waves, which project further than sound from conventional speakers.

The speakers work by converting an electric signal into sound. Usually, the signal is used to generate a varying magnetic field, which in turn vibrates a mechanical cone, so producing the sound.

The Flat Flexible Loudspeaker technology brings together thin conducting and insulating materials, resulting in the development of a flexible laminate. When activated by an electrical signal, the laminate will vibrate and produce sound.

The developers say the speaker laminate operates as a perfect piston resonator. The entire diaphragm therefore radiates in phase, forming an area source. The wave front emitted by the vibrating surface is phase-coherent, producing a plane wave with very high directivity and very accurate sound imaging. In translation: the speakers produce crisp, clear sound in big, noisy spaces.

Warwick Audio Technologies is currently in negotiations with a number of commercial partners and expects to launch its first commercial product later this year.