We present here a basic model for the synthesis of source spaciousness over loudspeaker arrays. This model is based on two experiments carried out to quantify the contribution of early reflections and reverberation to the perception of source spaciousness.

Wave field synthesis is a spatial sound field reproduction technique aiming at authentic reproduction of auditory scenes. Its theoretical foundation has been developed almost 20 years ago and has been improved considerably since then. Most of the original work on wave field synthesis is restricted to the reproduction in a planar listening area using linear loudspeaker arrays. Extensions like ar...

The perceived sound quality of small loudspeaker systems with and without digital optimization was empirically evaluated in a listening experiment. Further, the influence on the results of the presentation order of the two versions was investigated, as well as a self-evaluation of potential use for variance reduction. The systems were optimized by means of FIR filters. The two versions of each ...

Multichannel microphone array designs often use the localisation curves that have been derived for 2-0 stereophony. Previous studies showed that side and rear perception of phantom image locations require somewhat different curves. This paper describes an experiment conducted to determine localisation curves using an octagonal loudspeaker setup. Various signals with a range of interchannel time...

Spatial encoding refers to the representation of a sound field which allows storage and transmission of the latter. In the Ambisonics context, sound fields can be spatially encoded when their spherical wave spectrum is bandlimited. The process of deriving appropriate loudspeaker driving signals in order to reproduce an encoded sound field is known as spatial decoding. Care has to be taken when ...

This article describes a new test environment and materials with the potential to measure performance differences among different hearing aid signal processing methods and features. Normative data suggest a linearly predictable increase in difficulty on a speech-in-noise task as the masker changes from random noise to multiple-talker speech, and the number of talkers increases. Data collected w...

Sound fields are essentially band-limited phenomena, both temporally and spatially. This implies that a spatially sampled sound field respecting the Nyquist criterion is effectively equivalent to its continuous original. We describe Sound Field Reconstruction (SFR)—a technique that uses the previously stated observation to express the reproduction of a continuous sound field as an inversion of ...

A theory of smart loudspeaker arrays is described where a modified Fourier technique yields complex filter coefficients to determine the broadband radiation characteristics of a uniform array of micro drive units. Beam width and direction are individually programmable over a 180-degree arc, where multiple agile and steerable beams carrying dissimilar signals can be accommodated. A novel method ...

This work presents an audio beam loudspeaker that possesses the capability of emitting multiple audio beams into different directions at the same time. Ultrasonic loudspeakers applying parametric array technology are used to generate highly directional audible sound beams. The loudspeaker itself appears as a single device and can be mounted under the ceiling of a room in order to supply selecte...

Remote conferencing using desktop workstations is becoming commonplace. Typical audio conferencing hardware consists of a room loudspeaker (often built into the workstation) and a stand-alone microphone. Because there can be strong coupling between the loudspeaker and mike, undesirable echo signals can result. We propose to eliminate these signals using well understood echo cancellation algorit...