In the DIGNO S, this technology has been further enhanced, heightening acoustic pressure of low-pitch sounds for clearer audibility.

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The innovative tissue-conduction audio technology has been further enhanced from previous applications to heighten acoustic pressure of low-pitch sounds for even clearer, easier-to-hear audibility.

ENGADGET: Kyocera announces Digno S smartphone for Japan, promises over 18 hours of talk time in three colors

If you're looking for more technical details you'll find a link to the recently published paper titled, Dexterous manipulation of microparticles using Bessel-function acoustic pressure fields at the source.

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Acoustic shocks are defined as "any temporary or permanent disturbance of the functioning of the ear, or of the nervous system, which may be caused to the user of a telephone earphone by a sudden sharp rise in the acoustic pressure produced by it".

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In addition, all feature a specially designed Acoustic Optimizer that ensures dynamic sound and deep rich bass response, with optimum acoustical characteristics achieved by adjusting the sound pressure balance in front of and behind the diaphragm.

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