| 摘要 |
A loudspeaker is provided for high-quality and particularly stereophonic sound reproducing systems positioned close to a wall of a room. To reduce distortion due to that part of the reflected sound which arrives from substantially the same direction as the direct sound, the positioning of the sound radiating surfaces is such as to make the reflected sound from the wall arrive substantially in phase with the direct sound throughout a large frequency range, while at higher frequencies the reflected sound is attenuated by a sound absorber. The loudspeaker has a casing with a rear wall (5a). Loudspeaker units arranged to be the sound source for mid-range (12b) and/or high (14a) frequencies has the sound radiating surfaces (12b, 15a) at short distance (D2, D1) from the plane of the rear wall (5a) and facing slantwise forwards. A sound absorber (28a) at the side of the casing, in front of and near the plane of the rear wall (5a) and near the sound radiating surfaces (12b, 15a), serves to attenuate that part of the sound reflected by the room-wall which has wave-lengths shorter than eight times the shortest distance (D1, D2) of the sound radiating surfaces from the plane of the rear wall (5a). In stereophonic systems the left-hand and the right-hand loudspeakers form a mirror-image pair. |
