| 摘要 |
PURPOSE:To obtain a similar sense of listening through a headphone to that by a speaker by providing a convolution arithmetic unit receiving a spatial transfer function obtained from a spatial transfer function arithmetic unit and applying convolution calculation to a speaker reproduction signal so as to convert the signal into a headphone reproduction signal. CONSTITUTION:At first, an impulse signal is supplied to a left channel front speaker Lf from a sound source 18 and a signal is recorded by left/right microphones 13l, 13r imbedded in a dummy head. A spatial transfer function Hls, Hlo is obtained from the impulse response in this case. Of course, the spatial transfer function results from the composite of direct and reflected sounds and includes also the spatial transfer function of an ear hole. Thus, an impulse signal sent from 5 speakers Lf, Rf, Cf, Lr, Rr is being recorded sequentially to obtain 5 each of left and right spatial transfer functions. On the other hand, in the case of headphone reproduction, a convolution arithmetic unit 16 is connected to a surround decoder 23 connecting to a reproduced sound source 22 and the output of the convolution arithmetic unit 16 with a recording medium 17 mounted thereto is listened to by using a headphone 24. |
