Electrostatic electroacoustic transducers

An electrostatic electroacoustic device comprising:

• a first electrode, comprising a plurality of first electrode sections which are physically separated from each other;
• a second electrode, comprising a plurality of second electrode sections which are physically separated from each other;
• an electret assembly between the first electrode and the second electrode, the electret assembly including a first electret, a second electret and a conductive layer sandwiched between the first electret and the second electret, wherein the first and second electrets are charged with different electrical polarity;
• a plurality of first spacers, wherein each of the first spacers is connected with, and between, the electret assembly and a respective one of the first electrode sections;
• and
• a plurality of second spacers, wherein each of the second spacers is connected with, and between, the electret assembly and a respective one of the second electrode sections,
• wherein the electret assembly being capable of vibratory motion relative to the first electrode and the second electrode based on an audio signal applied to the first electrode and the second electrode.

An electrostatic electroacoustic device comprising:

• a first acoustic unit configured to serve as a first sound channel for a first frequency part of an audio signal;
• and
• a second acoustic unit configured to serve as a second sound channel for a second frequency part of the audio signal,
• wherein each of the first acoustic unit and the second acoustic unit comprises:
• a first electrode, comprising a plurality of first electrode sections which are physically separated from each other;
• a second electrode, comprising a plurality of second electrode sections which are physically separated from each other;
• a first electret between the first electrode and the second electrode, the first electret including at least one dielectric layer containing electrostatic charges;
• a second electret between the first electrode and the second electrode, the second electret including at least one dielectric layer containing electrostatic charges, wherein the first and second electrets are charged with different electrical polarity;
• a plurality of first spacers, wherein each of the first spacers is connected with, and between, a respective one of the first electrode sections and the first electret;
• a plurality of second spacers, wherein each of the second spacers is connected with, and between, a respective one of the second electrode sections and the second electret;
• and
• a conductive layer sandwiched between the first electret and the second electret, the conductive layer, the first electret and the second electret being capable of vibratory motion relative to the first electrode and the second electrode based on the audio signal.