Convention Paper
A Soundfield Microphone Using Tangential Capsules
AES Convention 129 · Paper 8240 · November 2010
Abstract
The traditional soundfield microphone is a tetrahedral array of pressure gradient microphones [1], the outputs of which are linearly combined in order to realize signals that are proportional to co-located microphones, one with omnidirectional sensitivity and three orthogonal microphones with figure-of-eight sensitivity. This configuration works well and has been the basis of commercial products for a number of years. This design with the capsules oriented radially can in principle be extended to higher orders, especially using geometries from other platonic solids such as the dodecahedron. Recently, a new array type has been disclosed [2,3] by Craven, Law, and Travis, comprised of pressure gradient sensors arranged with their principle axes oriented tangentially with respect to the center. Additional analysis has been performed and several prototypes were constructed and evaluated.
