AES E-Library

AES E-Library

An Alternative Ambisonics Formulation: Modal Source Strength Matching and the Effect of Spatial Aliasing

Document Thumbnail

Ambisonics synthesizes sound fields as a sum over angular (spherical/cylindrical harmonic) modes, resulting in the definition of an isotropically smooth angular resolution. This means, virtual sources are synthesized with outstanding smoothness across all angles of incidence, using discrete loudspeakers that uniformly cover a spherical or cylindrical surface around the listening area. The classical Ambisonics approach models the fields of these discrete loudspeakers in terms of a sampled continuum of plane-waves. More accurately, the contemporary concept of Ambisonics uses a continuous angular distribution of point-sources at finite distance instead, which is considerably easier to imagine. This also improves the accuracy of holophonic sound field synthesis and the analytic description of the sweet spot. The sweet spot is a limited area of faultless synthesis emerging from angular harmonics truncation. Additionally, playback with loudspeakers causes spatial aliasing. In this sense, the contemporary concept allows for a succesive consideration of the major shortcomings of Ambisonics: the limited sweet spot size and spatial aliasing. To elaborate on this, our paper starts with the solution of the nonhomogeneous wave equation for a spherical point-source distribution, and ends with a novel study on spatial aliasing in Ambisonics.

Authors:
Affiliations:
AES Convention: Paper Number:
Publication Date:
Subject:
Permalink: https://www.aes.org/e-lib/browse.cfm?elib=14936

Click to purchase paper as a non-member or login as an AES member. If your company or school subscribes to the E-Library then switch to the institutional version. If you are not an AES member and would like to subscribe to the E-Library then Join the AES!

This paper costs $33 for non-members and is free for AES members and E-Library subscribers.

Learn more about the AES E-Library

E-Library Location:

Start a discussion about this paper!


AES - Audio Engineering Society