| 摘要 |
PROBLEM TO BE SOLVED: To reproduce reverberation feeling while reproducing the direct sound of a desired acoustic field.SOLUTION: At least two microphones are disposed for each of two or more of circles having the axis of a cylindrical rigid baffle as the center and its circumferential direction as the circumferential direction. The at least two microphones are disposed in linear form. Here, i is assumed to be an index in the axial direction of the baffle, j is assumed to be an index in the circumferential direction of the baffle, and ω is assumed to be a frequency. A directivity control unit 2 forms, for a frequency-domain signal P(ω) generated on the basis of a signal acquired by the microphones, directivity in one predetermined direction for each index i in the z-axis direction by a discretionary directivity control technique, and generates a directivity formation post signal P(ω). A spatial frequency conversion unit 3 converts the directivity formation post signal P(ω) to a spatio-temporal frequency-domain signal P∼(ω) by Fourier transformation of space. A conversion filter unit 4 applies a filter F∼(ω) to the spatio-temporal frequency-domain signal P∼(ω) to generate a filter processing post signal D∼(ω). |
