| 摘要 |
A microphone capsule (40) for an in-the-ear hearing aid is disclosed. The capsule (40) can include a top plate (80) having first and second spaced openings defining front and rear sound inlets (83, 84), and a directional microphone cartridge (20) enclosing a diaphragm (21). The diaphragm (21) is oriented generally perpendicular to the top plate and divides directional microphone cartridge housing into a front chamber (22) and a rear chamber (24). A front sound passage (85) communicates between the front sound inlet and the front chamber, and a rear sound passage (86) communicates between th e rear sound inlet and the rear chamber. Front and rear acoustic damping resistors (81, 82) having selected resistance values are associated with the front and rear sound passages. The acoustic resistor pair provides a selecte d time delay, such as about 4 microseconds, between the front and rear sound passages. The use of two acoustic resistors instead of one levels the frequency response, compared to the frequency response provided by a rear acoustic damping resistor alone.
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