Frequency-domain sound field from the perspective of band-limited functions.

A model that approximates the sound field well is useful in various fields, such as acoustic signal processing and numerical simulation. We have proposed an effective model in which the wideband instantaneous sound field is regarded as an element of a spherically band-limited function space, using the reproducing kernel of that space. In this paper, the frequency-domain sound field is regarded as an element of some band-limited function space, and a representation of the field as a linear combination of the reproducing kernel in that space is proposed.

Direction-of-arrival estimation in half-space from single sample array snapshot.

Most existing direction-of-arrival (DOA) estimation algorithms are intended for single-frequency use. However, the majority of real sound fields are wideband, and the application of these techniques then becomes computationally expensive. In this paper, a fast DOA estimation method for use with wideband sound fields is constructed from only a single observation of the array signal based on the properties of a space of spherically band-limited functions.

Synthesis of musical instrument directivities with a single common loudspeaker (L).

This letter synthesizes musical instrument directivities by sequentially rotating a loudspeaker through multiple orientations. The synthesis is conducted in a spherical harmonic domain using the actual measured directivity of a commercial loudspeaker and an open database of musical instrument directivities. The letter further proposes a practically useful set of 26 loudspeaker orientations named Step45, which can be used to reproduce the target directivity as well as if the orientations were determined adopting mathematical methods that give equilibrium configurations.

Comment on "A theoretical framework for quantitatively characterizing sound field diffusion based on scattering coefficient and absorption coefficient of walls" [J. Acoust. Soc. Am. 128, 1140-1148 (2010)] (L).

The relationship between the acoustic scattering characteristics of materials and the degree of diffusion in enclosed acoustic spaces has recently attracted considerable research attention. Hanyu [J. Acoust.

Evaluation method of artificial acoustical environment: visualization of sound intensity.

Recent development of sound reproduction systems such as 5.1 surround produces artificial sound field inside the enclosure. The acoustic characteristic of the enclosure is an important factor which determines the quality of the sound field reproduction.