Patent ID: 8085969

Claim:
A method of recording sound, comprising: providing a planar magnetic transducer having a plurality of magnets and a tensioned diaphragm disposed between at least two of the magnets, wherein the diaphragm comprises a voice coil and wherein the magnets are arranged relative to each other such that: (a) a distance between the at least two of the magnets is at least 1 mm, (b) an average magnetic flux density between the at least two magnets in a plane perpendicular to the diaphragm is at least 0.35 T and substantially homogenous, and (c) an average magnetic flux density between a third magnet and one of the at least two magnets in a plane of the diaphragm is at least 0.3 T; wherein the diaphragm is sufficiently tensioned to allow recording of sound having a frequency of between 100 Hz and 20 kHz at a sound pressure level in a range of between 10 db and 140 db without compression and distortion; exposing the transducer to a sound to thereby generate an electric signal in the voice coil; and feeding the electrical signal from the voice coil to an amplifier.