High angular resolution planewave expansion
Svein Berge and Natasha Barrett
First-order ambisonics suffers from low angular resolution and a small sweet spot, and decoding to many loudspeakers does not help. Parametric decoding methods solve this problem, at the risk of introducing audible artifacts. A method for high angular resolution planewave expansion (HARPEX) is proposed, which combines the spatial sharpness of parametric methods with the physical correctness of linear decoding without introducing audible artifacts. In a formal listening test, a decoder using this method to decode first-order B-format signals scores much higher than maxrE decoding of the same signals, and similarly to maxrE decoding of third-order versions of the same signals.