Implementation of Segmented Circular-Arc Constant Beamwidth Transducer (CBT) Loudspeaker Arrays
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D.. (D. Keele, "Implementation of Segmented Circular-Arc Constant Beamwidth Transducer (CBT) Loudspeaker Arrays," Engineering Brief 210, (2015 October.). doi:
D.. (D. Keele, "Implementation of Segmented Circular-Arc Constant Beamwidth Transducer (CBT) Loudspeaker Arrays," Engineering Brief 210, (2015 October.). doi:
Abstract: Circular-arc loudspeaker line arrays composed of multiple loudspeaker sources are used very frequently in loudspeaker applications to provide uniform vertical coverage [1, 2, and 4]. To simplify these arrays, the arrays may be formed using multiple straight-line segments or individual straight-line arrays. This approximation has errors because some of the speakers are now no longer located on the circular arc and exhibit a “bulge error.” This error decreases as the number of segments increase or the splay angle of an individual straight segment is decreased. The question is: How small does the segment splay angle have to be so that the overall performance is not compromised compared to the non-segmented version of the array? Based on two simple spacing limitations that govern the upper operating frequency for each type of array, this paper shows that the bulge deviation should be no more than about one-fourth the center-to-center spacing of the sources located on each straight segment and that surprisingly, the maximum splay angle and array radius depends only on the number (N) of equally-spaced sources that are on a straight segment. As the number of sources on a segment increases, the maximum segment splay angle decreases and the required minimum array radius of curvature increases. Design guidelines are presented that allow the segmented array to have nearly the same performance as the accurate circular arc array.
@article{keele2015implementation,
author={keele, jr., d. b. (don)},
journal={journal of the audio engineering society},
title={implementation of segmented circular-arc constant beamwidth transducer (cbt) loudspeaker arrays},
year={2015},
volume={},
number={},
pages={},
doi={},
month={october},}
@article{keele2015implementation,
author={keele, jr., d. b. (don)},
journal={journal of the audio engineering society},
title={implementation of segmented circular-arc constant beamwidth transducer (cbt) loudspeaker arrays},
year={2015},
volume={},
number={},
pages={},
doi={},
month={october},
abstract={circular-arc loudspeaker line arrays composed of multiple loudspeaker sources are used very frequently in loudspeaker applications to provide uniform vertical coverage [1, 2, and 4]. to simplify these arrays, the arrays may be formed using multiple straight-line segments or individual straight-line arrays. this approximation has errors because some of the speakers are now no longer located on the circular arc and exhibit a “bulge error.” this error decreases as the number of segments increase or the splay angle of an individual straight segment is decreased. the question is: how small does the segment splay angle have to be so that the overall performance is not compromised compared to the non-segmented version of the array? based on two simple spacing limitations that govern the upper operating frequency for each type of array, this paper shows that the bulge deviation should be no more than about one-fourth the center-to-center spacing of the sources located on each straight segment and that surprisingly, the maximum splay angle and array radius depends only on the number (n) of equally-spaced sources that are on a straight segment. as the number of sources on a segment increases, the maximum segment splay angle decreases and the required minimum array radius of curvature increases. design guidelines are presented that allow the segmented array to have nearly the same performance as the accurate circular arc array.},}
TY - paper
TI - Implementation of Segmented Circular-Arc Constant Beamwidth Transducer (CBT) Loudspeaker Arrays
SP -
EP -
AU - Keele, Jr., D. B. (Don)
PY - 2015
JO - Journal of the Audio Engineering Society
IS -
VO -
VL -
Y1 - October 2015
TY - paper
TI - Implementation of Segmented Circular-Arc Constant Beamwidth Transducer (CBT) Loudspeaker Arrays
SP -
EP -
AU - Keele, Jr., D. B. (Don)
PY - 2015
JO - Journal of the Audio Engineering Society
IS -
VO -
VL -
Y1 - October 2015
AB - Circular-arc loudspeaker line arrays composed of multiple loudspeaker sources are used very frequently in loudspeaker applications to provide uniform vertical coverage [1, 2, and 4]. To simplify these arrays, the arrays may be formed using multiple straight-line segments or individual straight-line arrays. This approximation has errors because some of the speakers are now no longer located on the circular arc and exhibit a “bulge error.” This error decreases as the number of segments increase or the splay angle of an individual straight segment is decreased. The question is: How small does the segment splay angle have to be so that the overall performance is not compromised compared to the non-segmented version of the array? Based on two simple spacing limitations that govern the upper operating frequency for each type of array, this paper shows that the bulge deviation should be no more than about one-fourth the center-to-center spacing of the sources located on each straight segment and that surprisingly, the maximum splay angle and array radius depends only on the number (N) of equally-spaced sources that are on a straight segment. As the number of sources on a segment increases, the maximum segment splay angle decreases and the required minimum array radius of curvature increases. Design guidelines are presented that allow the segmented array to have nearly the same performance as the accurate circular arc array.
Circular-arc loudspeaker line arrays composed of multiple loudspeaker sources are used very frequently in loudspeaker applications to provide uniform vertical coverage [1, 2, and 4]. To simplify these arrays, the arrays may be formed using multiple straight-line segments or individual straight-line arrays. This approximation has errors because some of the speakers are now no longer located on the circular arc and exhibit a “bulge error.” This error decreases as the number of segments increase or the splay angle of an individual straight segment is decreased. The question is: How small does the segment splay angle have to be so that the overall performance is not compromised compared to the non-segmented version of the array? Based on two simple spacing limitations that govern the upper operating frequency for each type of array, this paper shows that the bulge deviation should be no more than about one-fourth the center-to-center spacing of the sources located on each straight segment and that surprisingly, the maximum splay angle and array radius depends only on the number (N) of equally-spaced sources that are on a straight segment. As the number of sources on a segment increases, the maximum segment splay angle decreases and the required minimum array radius of curvature increases. Design guidelines are presented that allow the segmented array to have nearly the same performance as the accurate circular arc array.
Author:
Keele, Jr., D. B. (Don)
Affiliation:
DBK Associates and Labs, Bloomington, IN, USA
AES Convention:
139 (October 2015)eBrief:210
Publication Date:
October 23, 2015Import into BibTeX
Subject:
Transducers
Permalink:
http://www.aes.org/e-lib/browse.cfm?elib=17886
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