| 摘要 |
<p>In an apparatus adapted to be used in an on-ear mode and in an off-ear mode a holder compartment (6) accommodates a first transducer (20) and a second transducer (25) and the holder compartment (6) is bounded by a bounding wall (7) formed with internal sound ports (10, 11) and at least one additional internal sound port (22), and an outer wall (3) formed with external sound ports (15, 16) is spaced at a distance from the bounding wall (7), and at least one additional external sound port (19) is provided between the bounding wall (7) and the outer wall (3), and the two transducers (20, 25) can be driven with useful signals of the same phase in the off-ear mode and with useful signals of opposite phase in the on-ear mode.</p> |
