Reproduction of multiple sound zones, in which personal audio programs may be consumed without the need for headphones, is an active topic in acoustical signal processing. Many approaches to sound zone reproduction do not consider control of the bright zone phase, which may lead to self-cancellation problems if the loudspeakers surround the zones. Conversely, control of the phase in a least-squares sense comes at a cost of decreased level difference between the zones and frequency range of cancellation. Single-zone approaches have considered plane wave reproduction by focusing the sound energy in to a point in the wavenumber domain. In this article, a planar bright zone is reproduced via planarity control, which constrains the bright zone energy to impinge from a narrow range of angles via projection in to a spatial domain. Simulation results using a circular array surrounding two zones show the method to produce superior contrast to the least-squares approach, and superior planarity to the contrast maximization approach. Practical performance measurements obtained in an acoustically treated room verify the conclusions drawn under free-field conditions.
References
1.
W. F.
Druyvesteyn
, R.
Aarts
, A.
Asbury
, P.
Gelat
, and A.
Ruxton
, “Personal sound
,” Proc. Inst. Acoust.
16
, 571
−585
(1994
).2.
W. F.
Druyvesteyn
and J.
Garas
, “Personal sound
,” J. Audio Eng. Soc.
45
, 685
−701
(1997
).3.
P.
Coleman
, P. J. B.
Jackson
, M.
Olik
, M.
Møller
, M.
Olsen
, and J. A.
Pedersen
, “Acoustic contrast, planarity and robustness of sound zone methods using a circular loudspeaker array
,” J. Acoust. Soc. Am.
135
, 1929
–1940
(2014
).4.
Y.
Wu
and T.
Abhayapala
, “Spatial multizone soundfield reproduction: Theory and design
,” IEEE Trans. Audio Speech Lang. Proc.
19
, 1711
−1720
(2011
).5.
A. J.
Berkhout
, D. de.
Vries
, and P.
Vogel
, “Acoustic control by wave field synthesis
,” J. Acoust. Soc. Am.
93
, 2764
−2778
(1993
).6.
D.
Ward
and T.
Abhayapala
, “Reproduction of a plane-wave sound field using an array of loudspeakers
,” IEEE Trans. Speech Audio Proc.
9
, 697
−707
(2001
).7.
K.
Helwani
, S.
Spors
, and H.
Buchner
, “The synthesis of sound figures
,” Multidimens. Syst. Signal Proc.
25
, 379
−403
(2014
).8.
M.
Poletti
, “An investigation of 2-D multizone surround sound systems
,” in Proceedings of the 125th AES Convention
, San Francisco
, CA
(October 2−5, 2008
).9.
N.
Radmanesh
and I. S.
Burnett
, “Generation of isolated wideband sound fields using a combined two-stage Lasso-LS algorithm
,” IEEE Trans. Audio Speech Lang. Proc.
21
, 378
−387
(2013
).10.
S.
Spors
, H.
Wierstorf
, A.
Raake
, F.
Melchior
, M.
Frank
, and F.
Zotter
, “Spatial sound with loudspeakers and its perception: A review of the current state
,” Proc. IEEE
101
, 1920
−1938
(2013
).11.
M. F. Simón
Gálvez
, S. J.
Elliott
, and J.
Cheer
, “A superdirective array of phase shift sources
,” J. Acoust. Soc. Am.
132
, 746
−756
(2012
).12.
J.
Cheer
, S. J.
Elliott
, and M. F. Simón
Gálvez
, “Design and implementation of a car cabin personal audio system
,” J. Audio Eng. Soc.
61
, 412
−424
(2013
).13.
J.
Choi
and Y.
Kim
, “Generation of an acoustically bright zone with an illuminated region using multiple sources
,” J. Acoust. Soc. Am.
111
, 1695
−1700
(2002
).14.
J.-H.
Chang
, C.-H.
Lee
, J.-Y.
Park
, and Y.-H.
Kim
, “A realization of sound focused personal audio system using acoustic contrast control
,” J. Acoust. Soc. Am.
125
, 2091
−2097
(2009
).15.
J.-H.
Chang
, J.-Y.
Park
, and Y.-H.
Kim
, “Scattering effect on the sound focused personal audio system
,” J. Acoust. Soc. Am.
125
, 3060
−3066
(2009
).16.
S. J.
Elliot
and M.
Jones
, “An active headrest for personal audio
,” J. Acoust. Soc. Am.
119
, 2702
−2709
(2006
).17.
M.
Jones
and S. J.
Elliott
, “Personal audio with multiple dark zones
” J. Acoust. Soc. Am.
124
, 3497
−3506
(2008
).18.
S. J.
Elliott
, J.
Cheer
, H.
Murfet
, and K. R.
Holland
, “Minimally radiating sources for personal audio
,” J. Acoust. Soc. Am.
128
, 1721
−1728
(2010
).19.
S. J.
Elliott
, J.
Cheer
, J.-W.
Choi
, and Y.
Kim
, “Robustness and regularization of personal audio systems
,” IEEE Trans. Audio Speech Lang. Proc.
20
, 2123
−2133
(2012
).20.
J.
Cheer
, S. J.
Elliott
, Y.
Kim
, and J.-W.
Choi
, “Practical implementation of personal audio in a mobile device
,” J. Audio Eng. Soc.
61
, 290
−300
(2013
).21.
M.
Shin
, S. Q.
Lee
, F. M.
Fazi
, P. A.
Nelson
, D.
Kim
, S.
Wang
, K. H.
Park
, and J.
Seo
, “Maximization of acoustic energy difference between two spaces
,” J. Acoust. Soc. Am.
128
, 121
−131
(2010
).22.
M.
Olik
, J.
Francombe
, P. J. B.
Jackson
, P.
Coleman
, M.
Olsen
, M.
Møller
, R.
Mason
, and S.
Bech
, “A comparative performance study of sound zoning methods in a reflective environment
,” in Proceedings of the 52nd AES International Conference
, Guildford, UK
(September 2−4, 2013
).23.
J.-H.
Chang
and F.
Jacobsen
, “Sound field control with a circular double-layer array of loudspeakers
,” J. Acoust. Soc. Am.
131
, 4518
−4525
(2012
).24.
T.
Betlehem
and P.
Teal
, “A constrained optimization approach for multi-zone surround sound
,” in IEEE International Conference on Acoustics, Speech Signal Processing (ICASSP)
, Prague
(May 22−27, 2011
), pp. 437
−440
.25.
Y.
Cai
, M.
Wu
, and J.
Yang
, “Sound reproduction in personal audio systems using the least squares approach with acoustic contrast control constraint
,” J. Acoust. Soc. Am.
135
, 734
−741
(2014
).26.
P.
Jackson
, F.
Jacobsen
, P.
Coleman
, and J.
Pedersen
, “Sound field planarity characterized by superdirective beamforming
,” Proc. Meet. Acoust.
19
, 055056
(2013
), presented at ICA2013, Montreal (June 2−7, 2013).27.
J.-W.
Choi
and Y.-H.
Kim
, “Manipulation of sound intensity within a selected region using multiple sources
,” J. Acoust. Soc. Am.
116
, 843
−852
(2004
).28.
J.-H.
Chang
, J.-W.
Choi
, and Y.-H.
Kim
, “A plane wave generation method by wave number domain point focusing
,” J. Acoust. Soc. Am.
128
, 2758
−2767
(2010
).29.
P.
Coleman
, P. J. B.
Jackson
, M.
Olik
, and J. A.
Pedersen
, “Optimizing the planarity of sound zones
,” in Proceedings of the 52nd AES International Conference
, Guildford
, UK
(September 2−4, 2013
).30.
M. F. Simón
Gálvez
, S. J.
Elliott
, and J.
Cheer
, “The effect of reverberation on personal audio devices
,” J. Acoust. Soc. Am.
135
, 2654
−2663
(2014
).31.
B. D. V.
Veen
and K. M.
Buckley
, “Beamforming: A versatile approach to spatial filtering
,” IEEE ASSP Mag.
5
, 4
−24
(1988
).32.
J.-H.
Chang
, J.-W.
Choi
, and Y.-H.
Kim
, “Reproduction of a plane-wave sound field based on wave number domain focusing: Comparison with ambisonics and WFS
,” in 8th International Conference on Motion and Vibration Control
, Daejeon
, Korea
(August 27−30, 2006
).33.
J.
Francombe
, R.
Mason
, M.
Dewhirst
, and S.
Bech
, “Determining the threshold of acceptability for an interfering audio programme
,” in Proceedings of the 132nd AES Convention
, Budapest
, Hungary
(April 26−29, 2012
).34.
K.
Baykaner
, C.
Hummersone
, R.
Mason
, and S.
Bech
, “The prediction of the acceptability of auditory interference based on audibility
,” in Proceedings of the 52nd AES International Conference
, Guildford
, UK
(September 2−4, 2013
).35.
S. G.
Norcross
, G. A.
Soulodre
, and M. C.
Lavoie
, “Subjective investigations of inverse filtering
,” J. Audio Eng. Soc.
52
, 1003
−1028
(2004
).© 2014 Acoustical Society of America.
2014
Acoustical Society of America
You do not currently have access to this content.
