| 摘要 |
PURPOSE: To make possible high quality acoustic reproducing by connecting the input terminal of a corresponding attenuating/correcting try pole to the input terminal of each loud speaker and connecting the combined output terminal of the attenuating/correcting try pole to the 2nd input terminal of a comparison amplifier. CONSTITUTION: An input signal concerning an input clamp 1 is amplified by the comparison amplifier 3 and added to the input terminal of a passive crossover 6. Then, the signal is separated into each frequency band by the passive crossover 6 means, and the separated signals are added to the input clamps of respective loud speakers 9 and 10. Voltages concerning the input clamps of the loud speakers 9 and 10 are attenuated by each corresponding attenuating/ correcting try pole 12 or 15, and added to the 2nd input terminal of the comparison amplifier 3. An auxiliary feedback is introduced into a frequency area larger than an acoustic band by a complementary attenuating/correcting try pole 18. Thus, even when loud speakers different in characteristic sensitivity and impedance are used by a feedback means, fine balanced frequency characteristic is achieved. |
