Near-Field Tangential Particle Velocities: Piston Radiator vs. QRD Phased Linear Array

Gifford T, Duffield M, Hayes J. Near-Field Tangential Particle Velocities: Piston Radiator vs. QRD Phased Linear Array. In: AES Conference: 2017 AES International Conference on Automotive Audio. Audio Engineering Society; 2017.pp. P5-3:1-8. Available from: https://aes.org/publications/elibrary-page/?id=19199

@inproceedings{Gifford2017_19199,
  author = {Gifford, Toby and Duffield, Malcolm and Hayes, Joe},
  title = {{Near-Field Tangential Particle Velocities: Piston Radiator vs. QRD Phased Linear Array}},
  booktitle = {AES Conference: 2017 AES International Conference on Automotive Audio},
  pages = {P5-3:1-8},
  year = {2017},
  month = aug,
  publisher = {Audio Engineering Society},
  url = {https://aes.org/publications/elibrary-page/?id=19199}
}

TY  - CPAPER
TI  - Near-Field Tangential Particle Velocities: Piston Radiator vs. QRD Phased Linear Array
AU  - Gifford, Toby
AU  - Duffield, Malcolm
AU  - Hayes, Joe
T2  - AES Conference: 2017 AES International Conference on Automotive Audio
SP  - 1
EP  - 8
M1  - Paper P5-3
PY  - 2017
DA  - 2017/08/06
UR  - https://aes.org/publications/elibrary-page/?id=19199
PB  - Audio Engineering Society
LA  - en
AB  - Loudspeakers in cars have practical constraints on their size and placement, so near-field and mid-field sound properties are of interest. The near-field of a circular piston has been well studied as an approximate model for a loudspeaker. Whilst SPL directivity of a piston is well understood, the polar pattern of particle velocity has received less attention. We calculate the radial and tangential components of the piston's particle velocity, and find that tangential velocity dominates at particular angles and frequencies, related to the ‘dips’ in SPL directivity. We contrast these results with an array of spherical drivers with phase delays determined by a QRD sequence, and find that the QRD array yields greater uniformity in both SPL directivity and particle velocity.
ER  -