| 摘要 |
PURPOSE:To obtain the desired directivity pattern almost constant independently of frequency, by delaying audio signals by different delay time and reducing the effect due to the change in the coefficient of directivity of speaker unit itself through the drive of a plurality of speakers by each delay output. CONSTITUTION:An audio signal from a signal source 7 is applied to delay circuits 8-1-8-n with different delay time, and each delay output is amplified at amplifiers 9-1-9-n corresponded to drive a plurality of speaker units 10-1, 10-n. The audio signal from a signal source 7 is split into two frequency band signals A, B at a frequency dividing filter 11, and after delaying the signals A, B at delay circuits 8-1-8-4 and 8-5-8-10, they are amplified at corresponding amplifiers 9-1-9-10 and added to speaker units 10-1-10-10. The effect by the change in the directivity coefficient of the speaker unit itself can be reduced and desired directivity pattern almost constant independently of frequency can be obtained. |
