Artificial reverberation algorithms are used to enhance dry audio signals. Delay-based reverberators can produce a realistic effect at a reasonable computational cost. While the recent popularity of spatial audio algorithms is mainly related to the reproduction of the perceived direction of sound sources, there is also a need to spatialize the reverberant sound field. Usually multichannel reverberation algorithms output a series of decorrelated signals yielding an isotropic energy decay. This means that the reverberation time is uniform in all directions. However, the acoustics of physical spaces can exhibit more complex direction-dependent characteristics. This paper proposes a new method to control the directional distribution of energy over time, within a delay-based reverberator, capable of producing a directional impulse response with anisotropic energy decay. The discussion explores a method using multichannel delay lines in conjunction with a direction-dependent transform in the spherical harmonic domain to control the direction-dependent decay of the late reverberation. The new reverberator extends the feedback delay network, retaining its time-frequency domain characteristics. The proposed directional feedback delay network reverberator can produce nonuniform direction-dependent decay time, suitable for anisotropic decay reproduction on a loudspeaker array or in binaural playback through the use of ambisonics.
Alary, Benoit; Politis, Archontis; Schlecht, Sebastian; Välimäki, Vesa
Affiliations: Acoustics Lab, Dept. of Signal Processing and Acoustics, Aalto University, Espoo, Finland;Faculty of Information Technology and Communication Sciences, Tampere University, Tampere, Finland;International Audio Laboratories Erlangen, Erlangen, Germany;Acoustics Lab, Dept. of Signal Processing and Acoustics, Aalto University, Espoo, Finland(See document for exact affiliation information.)
JAES Volume 67 Issue 10 pp. 752-762; October 2019
Publication Date: October 25, 2019
Download Now (463 KB)
No AES members have commented on this paper yet.
If you are not yet an AES member and have something important to say about this paper then we urge you to join the AES today and make your voice heard. You can join online today by clicking here.