Panasonic has developed a patent-pending low-range sound reproduction method, “Nano Bass Exciter,” to reproduce high fidelity sound for compact speakers.

The method is achieved by placing a porous carbon material within the loudspeaker cabinet, enabling small and/or thin speakers used in a range of products such as audio-visual (AV) equipment and mobile terminals to produce the industry’s highest level of rich low-range sounds.

The “Nano Bass Exciter” uses a porous carbon material with nanometer-sized minute pores that control the concentration of air molecules in the speaker. When low-range sound is reproduced, large amplitude vibrations of the diaphragm momentarily increase the air pressure within the loudspeaker cabinet. The “Nano Bass Exciter” absorbs the air molecules and decreases the air pressure, allowing the diaphragm in a compact speaker to move in the same manner as the diaphragm in a large loudspeaker cabinet. As a result, compact equipment can reproduce high fidelity low-range sound.

The “Nano Bass Exciter” achieves twice as much volume of low-range sounds as Panasonic’s conventional speakers, allowing rich sound reproduction with high fidelity. The new method can reproduce the low-range sound equivalent to that produced by conventional speakers with larger cabinet volume.

It also enables ultra-compact speakers used for mobile terminals to produce a sound effect closer to that of home AV equipment speakers. However, because it is difficult for air molecules to be absorbed by the carbon material at higher sound frequencies, applications in ultra-compact speakers for mobile terminals have shown limited effect. These technologies have therefore only been adopted for a few home AV equipment speakers.

Panasonic is considering applying the new method to future product design including speakers for home AV equipment and mobile terminals.