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TRANSCRIPT
l-acoustics sound solutions: PERFORMING ARTS CENTERS
PHOTO CREDITS - COVER TOP LEFT: Hollywood Bowl, Ramesh Shihora
BOTTOM: Guangzhou Opera House and Copenhagen Opera House
A SOUND PARTNER FOR PERFORMING ARTS CENTERS 5
FROM ThE DESIGN PhASE... 7Outstanding throw - Hollywood Bowl Directivity control - Bamboo Nightclub 360° coverage - Danish Radio Concert Hall
...ThROUGh TO INTEGRATION 15Mobile system - Olivier Theatre, National Theatre Discrete integration - Chongqing Grand Theatre
...AND bEyOND 21Faithful to vision - Guangzhou Opera HouseDiversified productions - Salle Pleyel
REFERENCES 26Performing arts portfolio White papers
ENvIRONMENTAl CREDENTIAlS 30
Cédric MONTREzOR Director of Application, Install
When the founder of L-ACOUSTICS, Dr. Christian Heil, invented the V-DOSC system - the very first line source system featuring the exclusive WST® technology in 1992 - it revolutionized the professional audio industry.
Since 1984, a large body of theoretical research and experience is behind every system that L-ACOUSTICS develops. Today, L-ACOUSTICS sound systems are considered the #1 choice for internationally recognized venues ranging from the Hollywood Bowl, the Beijing Opera House, the Olivier Theatre, part of the National Theatre, in London, and countless other facilities worldwide.
As the live performance business continues to evolve, performing arts centers are increasingly required to provide excellence in sound reproduction, by artists, productions and audiences alike. This performing arts center brochure presents a select number of performance venue challenges and solutions tackled by owners, consultants, engineers and contractors with L-ACOUSTICS systems. From the early stages of design through to system commissioning, every performing arts sound system project presents its own unique set of constraints, objectives and challenges. With L-ACOUSTICS, we always find the solution. We look forward to delivering The Best Sound to your audiences in opera houses, theatres, live clubs and performing arts centers across the globe.
introduction
“THe TeAM AT L-ACOUSTICS AND USe OF SOUNDVISION ReALLy MADe WHAT COULD HAVe BeeN AN exHAUSTIVe PROCeSS A MUCH SIMPLeR MeTHOD LeADING TO THe PRIMe SOLUTION.”Sam Moergen, LiveSpace Project Designer - Epikos Church
Shanghai Oriental Arts Centre
5
DElIvERING AN IMMERSIvE CONCERT SOUND ExPERIENCE FOR EvERy AUDIENCE MEMbER.
With a good sound system, everyone enjoys the show. L-ACOUSTICS’ number one goal is to create an unprecedented sonic experience for the audience, with easily reconfigurable and widely accepted sound systems.
Combining breathtakingly high-impact sound reinforcement with stunning transparency, our systems “disappear” behind artistic performances, providing a truly immersive experience for the audience. Our high-quality systems allow performing arts centers to become truly multi-purpose venues, with the potential to create or enhance revenue streams.
How is this achievement possible? L-ACOUSTICS has been designing reference line array systems for more than20 years. Our exclusive technologies, providing enhanceddirectivity control, allow L-ACOUSTICS to:
• provide consistent Sound Pressure Level, and sonicexperience, to every audience member
• enhance the intelligibility of the system, ideal for spoken word messages
• offer energy savings and system set-up flexibility
L-ACOUSTICS speakers focus all of their sonic energy on a particular segment of the audience. This reinforces an exceptional preservation of the acoustics of your venue.
A PARTNER FOR PERFORMING ARTS CENTERS
Developed for sound designers, SOUNDVISION is dedicated to the acoustical and mechanical simulation of L-ACOUSTICS systems. It is the first 3D sound design program capable of real time calculation of SPL and visualization of system coverage for complex sound system and venue configurations. System time alignment of multiple loudspeakers or arrays can be visualized with delay mode and the mechanical data provides detailed set-up information for installers and riggers.
“IT GIVeS yOU A GReAT SeNSe OF SeCURITy TO kNOW IN ADVANCe HOW yOUR INVeSTMeNT IS GOING TO PeRFORM, AND eVeN BeTTeR WHeN IT PeRFORMS exACTLy AS WAS PReDICTeD ON SOUNDVISION.”Christian Søvad, Technical Head at the Musikhuset Esbjerg - Esbjerg Performing Arts Centre
FROM ThE DESIGN PhASE...
7
POwERFUl ACOUSTIC SIMUlATION TOOlS
L-ACOUSTICS has developed a powerful design tool dedicated to the needs of consultants and system contractors. SOUNDVISION projects* sound simulations according to the physics of light, creating a visual representation of your “sound vision”. L-ACOUSTICS
SOUNDVISION is the first real time 3D sound design program capable of ‘‘showing’’ sound sources as if they were light projections. SOUNDVISION allows sound designers to visually design and optimize the performance of L-ACOUSTICS sound systems (in performing arts centers). This intuitive ‘‘what you see is what you get’’ visual approach provides the greatest speed and accuracy in:
• predicting and adjusting the sound design according to the exact geometry of the facility
• providing equipment options to balance between soundpressure level and budget
FlExIblE MEChANICAl DESIGN
All L-ACOUSTICS sound systems are engineered to be adapted to any environment and come with a rigging system that does not require any additional mechanical development. The rigging, derived from our touring systems, enables system mobility for special productions, fixed installation mechanical calculations, and quick reconfiguration whenever needed. The mechanical behavior of the sound system is integrated into SOUNDVISION. This enables a fast, predictable and secure mechanical simulation that consultants and system integrators can rely on. With L-ACOUSTICS, the design phase of a sound system for performing arts centers brings an unprecedented level of predictability alongside the maximum efficiency.
* L-ACOUSTICS can provide electro-acoustic modules to offer compatibility with third party software such as EASE, CATT, LARA and ODEON.
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CAPACITy
18 000
“It literally stopped me in my tracks as I stepped out into one of the promenades…there was no discernible drop in dynamic range, volume or quality.”Paul Geller, Production Director - Hollywood Bowl
OUTSTANDING ThROWhOllyWOOD BOWl
EqUIPMENT lIST
32 x k1
8 x k1-SB
8 x kARA
8 x ARCS II
16 x SB28
8 x kARA
12 x 5 xT
30 x LA8
4 x LA4
lOCATION
Los Angeles, USA
FROM ThE DESIGN PhASE...
9
ChAllENGE
hollywood bowl is a famous outdoor venue, with an audience capacity of 18 000 across a 450 feet (137 meter) incline. This spectacular audience depth presents a major coverage challenge. The system must throw high frequencies far into the distance. It must also control the differential attenuation of low frequencies, which tend to progressively thin out the tonal balance towards the outermost seats. Finally, the noise pollution of the system must be reduced to a minimum in the urban Hollywood location.
SOlUTION
The LA Philharmonic board oversaw a blind comparative evaluation of leading manufacturers. The L-ACOUSTICS k1 line source system was chosen unanimously, bringing additional SPL and a smoother horizontal coverage. The left and right line sources of 16 x k1 were optimized by a further 4 x k1-SB LF enclosures to control and throw the LF contents. The radiation pattern of low frequencies is squeezed vertically projecting acoustic energy to the back of the audience.
RESUlTS
The k1 line source system provides 105 dB of max SPL (102 dB on the previous system) on 95% of the audience depth with a tolerance of 3 dB. The tonal balance measured from the front seat positions shows an LF contour of 15 dB. In addition, the superior control of HF dispersion contributes to an additional 6 dB of rejection over the previous system, contributing to a significant reduction in noise pollution to the surrounding neighborhood.
System cut view
Frequency response curve
90 1404510
Distance (m)5
0
10
15
20
25
30
35
Hei
ght (
m)
30 feet / 10 meters 150 feet / 45 meters 300 feet / 90 meters
130
120
110
100
90
50 100 200 500 1k 2k 5k 10k
10
EqUIPMENT lIST
14 x kUDO
10 x SB28
4 x ARCS WIDe
6 x 12xTi
2 x SB18
6 x 5xT
10 x LA8
2 x 112P
2 x SB15P
CAPACITy
1 200
lOCATION
Miami Beach, USA
“Bamboo Club knew they wanted the L-ACOUSTICS
brand because all of the world’s top DJs - including Tiesto, Avicii, Swedish House Mafia - request it as their first choice.”Nick Assunto, CEO - Audio Formula
DIRECTIvITy CONTROlBAMBOO NIGhTClUB
FROM ThE DESIGN PhASE...
11
ChAllENGE
bamboo Nightclub, with a standing capacity of just 1 200, wished to create the live experience of a large concert venue, helping to attract the very best talent amongst the top world class DJs. The sound system had to be capable of handling both concerts and DJ performances, delivering high SPL levels and a LF tonal balance capable of handling both rock and electro program material. The highly reverberant space was a major acoustic challenge.
SOlUTION
The main L/R concert system consists of 4 x kUDO variable curvature line sources with adjustable k-LOUVeR horizontal directivity and 4 x cardioid SB28 subs on each side of the stage frame. Opposite the stage two additional clusters of 3 x kUDO are activated for DJ performances. Additional 6 x 12xTi and 4 x ARCS WIDe delays cover the rear audience area while 2 x SB28 are hidden underneath the central catwalk for infrasonic reinforcement.
RESUlTS
The kUDO/SB28 sound system delivers high SPL, spectacular impact and LF contour. A low reverberation time is maintained by the kUDO k-LOUVeRS, avoiding the highly reflective marble tiles and LeD walls. In the LF region the cardioid configuration of the SB28 subwoofers minimizes the room excitation. Both DJs and bands have been impressed with the performance of the sound reinforcement. The club has quickly become one of Miami’s most popular ‘‘buzz’’ venues.
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CAPACITy
1 800
“The sound system covers a complex audience geometry with an identical and transparent acoustic signature for every seat.”
Erik Falck, Technical Director - Matrix Sales
360 DEGREE COvERAGEDANISh RADIO CONCERT hAll
EqUIPMENT lIST
6 x kUDO
32 x kIVA
12 x kILO
8 x SB118
5 x 115xT HiQ
4 x 12xT
6 x 8xT
3 x LA8
10 x LA4
lOCATION
Copenhagen, Denmark
FROM ThE DESIGN PhASE...
13
ChAllENGE
The Danish Radio Concert hall is a multi-purpose venue, providing a home for the Danish National Radio Symphony Orchestra. The 1 800 capacity audience wraps 360° around a center stage in a complex patchwork of multiple asymmetric seating arrangements. The acoustician added reflective surfaces to modulate the reverberation time from 1.5s to 1.9s (when the venue is occupied), creating an additional challenge.
SOlUTION
The system is configured with front, rear and side sound sources located in the ceiling and flown on the canopy at a height of approximately 15 m above ground level. The audience coverage is divided into seven horizontal sectors (one 60° mono kUDO cluster for the front audience and six 50° kIVA clusters) which overlap to recreate stereo imaging. With different cluster sizes determined by the vertical coverage requirements, SPL and tonal balance homogeneity is addressed by adjusting inter-element angles between cabinets and the L-ACOUSTICS DSP array morphing tool.
RESUlTS
The listener experiences the same tonal balance and identical SPL level from each of the line sources located around the concert hall. The sound system is also totally transparent, respecting the acoustic signature of Nagata Acoustics. The line sources offer a high vertical SPL rejection outside of the coverage area, preserving the stage and maintaining a high immunity to feedback. The horizontal directivity of kIVA of 90° contributes to a 30° overlap between zones for better sound spatialization.
Frequency response curves
Position # 1 Position # 2 Position # 3
125
115
105
95
85
50 100 200 500 1k 2k 5k 10k
“THey TOOk PHOTOS AND MeASUReMeNTS OF THe VeNUe, AND THeN GAVe US SeVeRAL POTeNTIAL SySTeM DeSIGNS TO CHOOSe FROM. IT MADe IT exTReMeLy eASy TO SHOW MANAGeMeNT HOW AN L-ACOUSTICS SySTeM WOULD OVeRCOMe THe OBSTACLeS AND CHALLeNGeS THAT OUR PReVIOUS SySTeM HAD FAILeD TO ADeQUATeLy ADDReSS.’’ Chris Weathers, Production Director - Live Nation Central Region
Julien Laval, Application Engineer, Install - L-ACOUSTICS
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...ThROUGh TO INTEGRATION
15
A NETwORK OF CERTIFIED SySTEM INTEGRATORS
L-ACOUSTICS carefully selects certified system integrators. Our System Integrator Charter outlines three key commitments:
• tailored services from specification to post-integration stage
• adoption of recommended technical standards to ensurethe consistency and predictability of performance and operational safety of the sound system
• in-house trained personnel on multiple aspects of integration of L-ACOUSTICS
L-ACOUSTICS certifies its system integrators with official training seminars. Technical and engineering personnel are trained on theory, sound design, system set-up and rigging procedures for all systems.
STANDING bEhIND EACh PROJECT
L-ACOUSTICS stands behind the integrators and the consultants for every single installation project, from project analysis, system specification, engineering, integration, commissioning and maintenance services ensuring that the
system will work at its best. L-ACOUSTICS clients benefit from dedicated L-ACOUSTICS manufacturer support.
Performing arts centers can expect the highest quality of service, whether the project is design built by an integrator or specified by a consultant and awarded through a bidding process.
STREAMlINED INTEGRATION
With 30 years of designing touring systems, L-ACOUSTICS
manufactures turnkey sound systems with an integrated rigging approach and an architecturally-friendly RAL color program. No custom rigging is required to install an L-ACOUSTICS sound system, which dramatically reduces design and installation time. L-ACOUSTICS amplified controllers provide an eQ station, control and monitoring, DSP processing, and limiters all in one package, providing a full plug and play system for straightforward integration.
System Integrator
C E R T I F I E D P R O V I D E RC E R T I F I E D P R O V I D E R
1616
CAPACITy
1 160
MOBIlE SySTEM OlIvIER ThEATRE, NATIONAl ThEATRE
EqUIPMENT lIST
6 x ARCS II
18 x kARA
6 x SB18
8 x 8xTi
2 x 12xTi
8 x LA8
lOCATION
London, Uk
“The Olivier Theatre is an extremely tricky theatre for sound. I was knocked out when I first heard the kARAs in this space. The sound is superbly detailed, and the system is extremely powerful.”
Paul Arditti, Theatre Sound Designer
17
...ThROUGh TO INTEGRATION
17
ChAllENGE
The Olivier Theatre, named after the National Theatre’s first Director, Laurence Olivier, is one of the most prestigious producing theatres worldwide. As a production house, luminaries of sound design take responsibility for each production, imparting their theatrical sound design stamp on the venue. The new sound system had to be mobile enough to be reconfigured production after production and to offer maximum flexibility to support the artistic vision of the guest sound designers.
SOlUTION
A sound system ‘‘toolbox’’ based upon two technologies is provided. The reproduction of vocals is served by a fixed constant curvature central cluster of 6 x ARCS II (completed by a ring of 8xTi balcony delays) with a horizontal coverage of 135°. A mobile kARA modular line source system is deployed for the reproduction of modern music in a left right arrangement of 9 x kARA enclosures with 3 x SB18 to deliver LF contour, impact and a highly transient response. The sonic space can be divided into different zones according to production demands.
RESUlTS
With the diverse range of theatre the Olivier produces and the need to cater for the requests of the world class sound designers who work there, L-ACOUSTICS have designed a flexible system that can cater for every eventuality and allow the venue to host multiple productions on a weekly basis.
1818
CAPACITy
1 850
DISCRETE INTEGRATION ChONGQING GRAND ThEATRE
lOCATION
Chongqing, China
EqUIPMENT lIST
28 x kIVA
8 x kILO
4 x 115xT HiQ
4 x SB28
28 x 108P
24 x 112P
4 x SB15P
6 x LA8
“L-ACOUSTICS have always been a world-famous brand. The unique line source technology fits well into the architectural style and structure of the theatre.”
Liu Yongyao, Technical Director - Leafun
19
...ThROUGh TO INTEGRATION
19
ChAllENGE
The Chongqing Grand Theatre is a landmark in the region for its striking sculptural design. The Grand Theatre is designed as a world-class venue hosting opera, dance, drama, ballet, symphony and other large-scale variety shows. The integration of the sound system had to fulfill exacting architectural constraints.
SOlUTION
In the Grand Theatre, left and right arrays, encompassing 14 x kIVA ultra-compact line source array cabinets with 4 x kILO low frequency extensions have been flown on either side of the proscenium arch. An additional 2 x 115x HiQ cabinets have also been installed on each side of the stage for infill. 4 x SB28 high-power subwoofers can be moved into different places. A fill system composed of 28 x 108P and 12 x 112P self-powered coaxials has also been installed.
RESUlTS
The kIVA system provided a clean, seamless integration choice, with enhanced mobility for moving and installing the speakers according to the event taking place in the theatre. The senior designer from Muller-BBM, Mr kuemmel said, “This is the best theatre that I’ve participated in designing in China. Despite the effects of the architectural acoustic environment or the sound reinforcement effect of the theatre, L-ACOUSTICS speakers have provided the best sound for this theatre.”
L-ACOUSTICS systems are entirely engineered and manufactured in France. The company has a presence in 60 countries, employs 200 people worldwide with 25 languages spoken by employees. Five principles are at the heart of L-ACOUSTICS culture: innovation, consistent and predictable performance, a turnkey system approach, support and education of users and the longevity and durability of systems.
“I CAN SO COMFORTABLy SAy THAT We HAVe THe FINeST SOUNDING SySTeM IN THe WORLD. NOBODy CAN TOP IT. I HAVe TOUReD THe WORLD WITH THe PHILHARMONIC FOR yeARS PeRFORMING JUST ABOUT eVeRyWHeRe ONe COULD IMAGINe AND I’Ve NeVeR HeARD A SySTeM THAT COMeS CLOSe TO THIS.” Paul Geller, Production Director - Hollywood Bowl
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...AND BEyOND
21
REvENUE GENERATION
A high performance and flexible sound system contributes to revenue generation. Offering a high impact, immersive experience attracts more audiences, artists and productions. Multi-use facilities can appreciate easy-to-reconfigure L-ACOUSTICS systems. Access to L-ACOUSTICS Rental Network inventories means that additional components can be easily sourced for diverse productions needs, reinforcing multi-strand revenue stream potential.
lONG TERM INvESTMENT
L-ACOUSTICS systems boast an exceptional durability.For over 30 years L-ACOUSTICS systems have been used as touring and live performance systems on a daily basis in challenging environments. Our earliest clients, including for example, Le Palais des Congrès de Paris or the Lille Grand Palais, have been enjoying their V-DOSC sound systems for more than fifteen years. V-DOSC continues to deliver outstanding performances today. All L-ACOUSTICS systems come with a warranty of five years.
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This sound reinforcement system provides a perfect reproduction of natural and electro-acoustic sound that works very well with various types of large-scale performances”
Wilson Zhao, Supervisor of Sound - Guangzhou Opera House
FAIThFUl TO ARChITECTURAl AND ACOUSTICIANS’ vISIONSGUANGzhOU OPERA hOUSE
CAPACITy
1 804
EqUIPMENT lIST
16 x kUDO
6 x SB28
10 x dV-DOSC
2 x dV-SUB
10 x ARCS
28 x 8xT
33 x 12xT
4 x 115xT HiQ
13 x LA4
14 x LA8
lOCATION
Guangzhou, China
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...AND BEyOND
23
ChAllENGE
The Guangzhou Opera house is rated as one of the China’s top three theatres and the best-equipped performing arts center in southern China. Acoustic engineers and architects were briefed to design a space to accommodate diverse performances. Sir Harold Marshall designed a unique “encircling” grand auditorium, which continues the asymmetrical streamlined architectural design of Ms. Zaha Hadid. It features a 1.6 seconds of reverberation time when at full capacity, ideal for both symphonic and drama works. The sound system had to fit within the architectural and acoustic design.
SOlUTION
The sound system consists of 8 x kUDO and 2 x SB28 per side and a central channel of 10 x dV-DOSC line sources. The three arrays are concealed in the ceiling. each side of the stage apron features 5 x ARCS constant curvature line sources. Fill systems feature a total of 28 x 8xT coaxial enclosures. The sound effects system consists of 33 x 12xT coaxial enclosures and 2 x SB28 subs.
RESUlTS
Since its opening ceremony in June 2010, the GOH has hosted almost 1 000 shows. “Mamma Mia!”, “Cats” and “The Adams Family” have been produced alongside world opera masterpieces such as “Turandot”, “La Tosca”, “Madame Butterfly” and famous ballets such as “Swan Lake” and “The Nutcracker”. The GOH has been the subject of international recognition and praise for its exceptional acoustics, sound system neutrality, and performance.
2424
CAPACITy
1 913
DIvERSIFIED PRODUCTIONSSAllE PlEyEl
lOCATION
Paris, France
EqUIPMENT lIST
12 x kUDO
9 x dV-DOSC
4 x dV-SUB
13 x LA48a
4 x 12xT
“Having had extensive experience with L-ACOUSTICS sound systems, I am extremely happy to be responsible for operating the system in such a prestigious place.”
Sebastien Moreau, Sound Engineer - Salle Pleyel
25
...AND BEyOND
25
ChAllENGE
The Salle Pleyel is one of the most prestigious classical music venues in France with impressive art deco interiors. The current resident ensembles are the Orchestre de Paris and the Orchestre Philharmonique de Radio France. A major acoustic renovation program was implemented in the shoe-box venue between 2004 and 2006 by ARTeC. Part of this program addressed updating the sound system to diversify the venues’ income stream.
SOlUTION
A fixed central cluster of 9 x dV-DOSC modular line source enclosures is deployed to cover the announcements for the philharmonic concerts. For contemporary music from jazz to pop in a black box stage proscenium, a left right system composed of 6 x kUDO enclosures per side is completed by a 12xT stereo in-fill system. For higher SPL and impact, further systems of 3 x kUDO and 2 x SB28 can be added for the main parterre.
RESUlTS
With the new L-ACOUSTICS system installed, a much wider range of applications now takes place in the venue. Salle Pleyel now hosts performances of jazz, world music as well as symphonic orchestras. Recent guest artists include Chick Corea, Herbie Hancock, keith Jarrett, youssou N’Dour, Patti Smith, Laurent Garnier, Goran Bregovic and Paco de Lucia.
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Al Raha Theater Abu Dhabi - U.A.e
Alt Opera Frankfurt - Germany
Austin Performing Arts Center Austin, Tx - USA
Baku Opera Baku - Azerbaidjan
Brno Theater Brno - Czech Republic
Carpenter Performing Arts Center Long Beach, CA - USA
Cemal Resit Rey Concert Hall Istanbul - Turkey
Chunmu and Pohang Arts Hall Pohang - korea
Cité de la Musique Concert Hall Paris - France
Danish Radio Concert Hall Copenhagen - Denmark
Figueira Casino Theater Figueira Da Foz - Portugal
Fox Theater Pomona Pomona, CA - USA
Goteborg Concert Hall Goteborg - Sweden
Grand Auditorium Cultural Center Macao - China
The Grande-Duchesse Concert Hall Luxembourg
Guangzhou Opera House Guangzhou - China
Helsinki Music Hall Helsinki - Finland
Croatian National Theatre Split - Croatia
Hyogo Arts and Cultural Hall Hyogo - Japan
L’Orangerie du Botanique Brussels - Belgium
La Cigale Club Doha - Qatar
Lexington Opera House Lexington, kC - USA
Opéra Royal de Wallonie Liège - Belgium
Lille Grand Palais Congress Center Lille - France
Queensland Performing Arts Center Brisbane - Australia
Musical Dome Cologne - Germany
National Concert Hall Dublin - Ireland
National Doha Theater Doha - Qatar
Copenhagen Opera House, Copenhagen - Denmark Suzhou Science and Cultural Centre, Suzhou - China
REFERENCES performing arts center installations portfolio
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National Grand Theater Beijing - China
Damascus Opera House Damascus - Syria
Copenhagen Opera House Copenhagen - Denmark
Oslo Theater Hall Oslo - Norway
Pallas Theater Athens - Greece
Salle Pleyel Paris - France
Cultural Village Theater Doha - Qatar
Radio City Music Hall New york, Ny - USA
Salle Raoul-Jobin Quebec - Canada
Royal Carre Theater Amsterdam - Netherlands
Royal Concert Hall Glasgow - Scotland
Salle des etoiles Concert Hall Monte-Carlo - Monaco
Sejong Cultural Center Seoul - korea
Seoul-Ax Concert Hall Seoul - korea
Shanghai Oriental Arts Center Shanghai - China
Shibuya-Ax Theater Tokyo - Japan
Staatstheater am Gartnerplatz Munich - Germany
Suzhou Science and Cultural Centre Suzhou - China
The esplanade Theater Studio Singapore
The Old Student House Helsinki - Finland
The Royal Danish Theater Copenhagen - Denmark
Umi Theater of Shiki Theatrical Company Tokyo - Japan
Vantaa Martinus Concert Hall Vantaa - Finland
For more reference information please visit: www.l-acoustics.com/installations www.l-acoustics.com/picture-gallery
Opéra Royal de Wallonie, Liège - Belgium Salle Raoul-Jobin, Quebec - Canada
28
of complex interference phenomena and thus opens the road to establishing the criteria for the effective coupling of sound sources and for the coverage of a given audience geometry in sound reinforcement applications.The derived criteria form the basis of what is termed Wavefront Sculpture Technology.
wavefront Sculpture
TechnologyAES Journal - vol. 51, n°10 - 2003The Fresnel approach in optics is introduced to the field of acoustics. Fresnel analysis provides
an effective, intuitive way of understanding complex interference phenomena and allows for the definition of criteria required to couple discrete sound sources effectively and to achieve coverage of a given audience geometry in sound-reinforcement applications. The derived criteria from the basis of what is termed Wavefront Sculpture Technology.
Sound Field Radiated
by Arrayed Multiple
Sound SourcesAES Convention Paper #3269 - 92nd AES Convention - 1992
How to know whether it is possible or not to predict the behaviour of an array when the behaviour of each element is known? Our purpose is to describe the sound field produced by arrays in such a way that criteria for “arraybility” can be defined.
wavefront Sculpture
TechnologyAES Convention Paper #5488 - 111th AES Convention - 2001We introduce Fresnel’s ideas in optics to the
field of acoustics. Fresnel analysis provides an effective, intuitive approach to the understanding
HEIL, URBAN AND BAUMAN
WAVEFRONT SCULPTURE TECHNOLOGY
AES 111TH CONVENTION, NEW YORK, NY, USA, 2001 SEPTEMBER 21–24
3
2 THE FRESNEL APPROACH FOR A CONTINUOUS LINE
SOURCE The fact that light is a wave implies interference phenomena when
an isophasic and extended light source is looked at from a given
point of view. These interference patterns are not easy to predict
but Fresnel, in 1819, described a way to semi-quantitatively picture
these patterns. Fresnel's idea was to partition the main light source
into fictitious zones made up of elementary light sources. The
zones are classified according to their arrival time differences to
the observer in such a way that the first zone appears in phase to
the observer (within a fraction of the wave length λ). The next
zone consists of elementary sources that are in-phase at the
observer position, but are collectively in phase opposition with
respect to the first zone, and so on. A more precise analysis shows
that the fraction of wave length is λ/2 for a 2-dimensional source
and λ/2.7 for a 1-dimensional source (please see appendix 2 for
further details). We will apply Fresnel’s concepts to the sound field of extended
sources. Let us consider first a perfectly flat, continuous and
isophasic line source. To determine how this continuous wave
front will perform with respect to a given listener position, we
draw spheres centered on the listener position whose radii are
incremented by steps of λ/2 (see figures 3 and 4). The first radius
equals the tangential distance that separates the line source and the
listener. Basically two cases can be observed: 1. A dominant zone appears: The outer zones are alternatively in-phase and out-of-phase. Their
size is approximately equal and they cancel each other out. We can
then consider only the largest, dominant zone and neglect all
others. We assume that this dominant zone is representative of the
SPL radiated by the line source. This is illustrated in Figure 3
where it is seen that for an observer facing the line source the
sound intensity corresponds roughly to the sound radiated by the
first zone. 2. No dominant zone appears in the pattern and almost no sound is
radiated to the observer position. Referring to figure 4, this
illustrates the case for an off-axis observer.
Figure 3: Observer facing the line source. On the right part (side view),
circles are drawn centered on the observer O, with radii
increasing by steps of λ/2. The pattern of intersections on the
source AB is shown on the left part (front view). These define the
Fresnel zones.
Figure 4: The observer O, is no longer facing the line source. The
corresponding Fresnel zones are shown on the left part (front
view). There is no dominant zone and individual zones cancel each
other off-axis. Moving the observation point to a few locations around the line
source and repeating the exercise, we can get a good qualitative
picture of the sound field radiated by the line source at a given
frequency. Note that the Fresnel representations of figures 3 and 4 are at a
single frequency. The effects of changing frequency and the on-
axis listener position are shown in Figure 5.
Figure 5: The effect of changing frequency and listener position.
As the frequency is decreased, the size of the Fresnel zone grows
so that a larger portion of the line source is located within the first
dominant zone. Conversely, as the frequency increases, a reduced
portion of the line source is located inside the first dominant zone.
If the frequency is held constant and the listener position is closer
to the array, less of the line source is located within the first
dominant zone due to the increased curvature. As we move further
away, the entire line source falls within the first dominant zone.
3 EFFECTS OF DISCONTINUITIES ON LINE SOURCE
ARRAYS In the real world, a line source array results from the vertical
assembly of separate loudspeaker enclosures. The radiating
transducers do not touch each other because of the enclosure wall
thicknesses. Assuming that each transducer originally radiates a
flat wave front, the line source array is no longer continuous. In
this section, our goal is to analyze the differences versus a
HEIL, URBAN AND BAUMAN WAVEFRONT SCULPTURE TECHNOLOGY
AES 111TH CONVENTION, NEW YORK, NY, USA, 2001 SEPTEMBER 21–24 2
fronts propagate with 3 dB attenuation per doubling of distance (cylindrical wave propagation) whereas in the far field there is 6 dB attenuation per doubling of distance (spherical wave propagation). It is to be noted that usual concepts of directivity, polar diagrams and lobes only make sense in the far field (this is developed in appendix 1). Considering next a line source with discontinuities, we also described a progressively chaotic behavior of the sound field as these discontinuities become progressively larger. This was confirmed in 1997 [3] when Smith, working on an array of 23 loudspeakers, discovered that 7 dB SPL variations over 1 foot was a common feature in the near field. Smith tried raised cosine weighting approaches in order to diminish this chaotic SPL and was somewhat successful, but it is not possible to have, at the same time, raised cosine weighting for the near field and Bessel weighting for the far field. In [1] we showed that a way to minimize these effects is to build a quasi-continuous wave front.
The location of the border between the near field and the far field is a key parameter that describes the wave field. Let us call dB the distance from the array to this border. We will make the approximation that if F is the frequency in kHz then λ=1/(3F) where λ is the wavelength in metres. Considering a flat, continuous line source of height H that is radiating a flat isophasic wavefront, we demonstrated in [1] that a reasonable average of the different possible expressions for dB obtained using either geometric, numerical or Fresnel calculations is:
( )FHHFd B
311
23
22 −=
where dB and H are in meters, F is in kHz. There are three things to note about this formula: 1) The root factor indicates that there is no near field for frequencies lower than 1/(3H). Hence a 4 m high array will radiate immediately in the far field mode for frequencies less than 80 Hz. 2) For frequencies above 1/(3H) the near field extension is almost linear with frequency. 3) The dependence on the dimension H of the array is not linear but quadratic. All of this indicates that the near field can extend quite far away. For example, a 5.4 m high flat line source array will have a near field extending as far as 88 meters at 2 kHz.
We also demonstrated in [1] that a line array of sources, each of them radiating a flat isophase wave front, will produce secondary lobes not greater than –12 dB with respect to the main lobe in the far field and SPL variations not greater than ± 3 dB within the near field region, provided that: ♦ Either the sum of the flat, individual radiating areas covers more than 80% of the vertical frame of the array, i.e., the target radiating area ♦ Or the spacing between the individual sound sources is smaller than 1/(6F) , i.e., λ/2. These two requirements form the basis of WST Criteria which, in turn, define conditions for the effective coupling of multiple sound sources. In the following sections, we will derive these results using the Fresnel approach along with further results that are useful for line source acoustical predictions. Figure 1 displays a cut view of the radiated sound field. The SPL is significant only in the dotted zone (ABCD + cone beyond BC). A more detailed description is deferred to Section 4.
Figure 1: Radiated SPL of a line source AD of height H. In the near field, the SPL decreases as 3 dB per doubling of distance, whereas in the far field, the SPL decreases as 6 dB per doubling of distance. It should be noted that different authors have come up with various expressions for the border distance:
dB = 3H Smith [3] dB = H/π Rathe [4] dB = maximum of (H , λ/6) Beranek [5] Most of these expressions omit the frequency dependency and are incorrect concerning the size dependence. Figure 2 illustrates the variation of border distance and far field divergence angle with frequency for a flat line source array of height = 5.4 m.
Figure 2: Representation of the variation of border distance and far field divergence angle with frequency for a flat line source array of height 5.4 metres.
___________________________________
Audio Engineering Society
Convention Paper Presented at the 111th Convention
2001 September 21–24 New York, NY, USA
This convention paper has been reproduced from the author's advance manuscript, without editing, corrections, or consideration
by the Review Board. The AES takes no responsibility for the contents. Additional papers may be obtained by sending request
and remittance to Audio Engineering Society, 60 East 42nd Street, New York, New York 10165-2520, USA; also see www.aes.org.
All rights reserved. Reproduction of this paper, or any portion thereof, is not permitted without direct permission from the
Journal of the Audio Engineering Society.
___________________________________
Wavefront Sculpture Technology
MARCEL URBAN, CHRISTIAN HEIL, PAUL BAUMAN
L-ACOUSTICS
Gometz-La-Ville, 91400 France
ABSTRACT We introduce Fresnel’s ideas in optics to the field of acoustics. Fresnel analysis provides an effective, intuitive approach to the understanding
of complex interference phenomena and thus opens the road to establishing the criteria for the effective coupling of sound sources and for the
coverage of a given audience geometry in sound reinforcement applications. The derived criteria form the basis of what is termed Wavefront
Sculpture Technology.
0 INTRODUCTION
This paper is a continuation of the preprint presented at the 92nd
AES Convention in 1992 [1]. Revisiting the conclusions of this
article, which were based on detailed mathematical analysis and
numerical methods, we now present a more qualitative approach
based on Fresnel analysis that enables a better understanding of the
physical phenomena involved in arraying discrete sound sources.
From this analysis, we establish criteria that define how an array of
discrete sound sources can be assembled to create a continuous line
source. Considering a flat array, these criteria turn out to be the
same as those which were originally developed in [1]. We also
consider a variable curvature line source and define other criteria
required to produce a wave field that is free of destructive
interference over a predefined coverage region for the array, as
well as a wave field intensity that decreases as the inverse of the
distance over the audience area. These collective criteria are
termed Wavefront Sculpture Technology1 (WST) Criteria.
1 MULTIPLE SOUND SOURCE RADIATION - A REVIEW
The need for more sound power to cover large audience areas in
sound reinforcement applications implies the use of more and more
sound sources. A common practice is to configure many
loudspeakers in arrays or clusters in order to achieve the required
1 Wavefront Sculpture Technology and WST are trademarks of L-
ACOUSTICS
sound pressure level (SPL). While an SPL polar plot can
characterize a single loudspeaker, an array of multiple
loudspeakers is not so simple. Typically, trapezoidal horn-loaded
loudspeakers are assembled in fan-shaped arrays according to the
angles determined by the nominal horizontal and vertical coverage
angles of each enclosure in an attempt to reduce overlapping zones
that cause destructive interference. However, since the directivity
of the individual loudspeakers varies with frequency, the sound
waves radiated by the arrayed loudspeakers do not couple
coherently, resulting in interference that changes with both
frequency and listener position.
Considering early line array systems (column speakers), apart from
narrowing of the vertical directivity, another problem is the
appearance of secondary lobes outside the main beamwidth whose
SPL can be as high as the on-axis level. This can be improved with
various tapering or shading schemes, for example, Bessel
weighting. The main drawback is a reduced SPL and, for the case
of Bessel weighting, it was shown that the optimum number of
sources was five [2]. This is far from being enough for open-air
performances.
In [1] we advocated the solution of a line source array to produce a
wave front that is as continuous as possible. Considering first a
flat, continuous and isophasic (constant phase) line source, we
demonstrated that the sound field exhibits two spatially distinct
regions: the near field and the far field. In the near field, wave
REFERENCES white papers
29
The Distributed
Edge Dipole (DED)
Model for Cabinet
Diffraction EffectsAES Journal - vol. 52, n°10 - 2004A simple model is proposed to account
for the effects of cabinet edge diffraction on the radiated sound field for direct-radiating loudspeaker components when mounted in an enclosure. The proposed approach is termed the Distributed edge Dipole (DeD) model since it is developed based on the kirchoff Approximation (kA) using distributed dipoles with their axes perpendicular to the baffle edge as the elementary diffractive sources. The DeD model is first tested against measurements for a thin circular baffle and is then applied to a real world loudspeaker that has a thick, rectangular baffle. The forward sound pressure level and the entire angular domain are investigated and predictions of the DeD model show good agreement with experimental measurements.
Performance audio +
intelligibility + evac
= ?? a loudspeaker
manufacturer’s take Institute of Acoustics - vol. 33. Pt. 6. - 2011Using several case studies, L-ACOUSTICS
will present working solutions to balancing high performance audio, STI requirements, and evacuation system integration through the use of line source array technology, loudspeaker monitoring, smart controller amplifiers, and network control and switching. This will serve as a launch pad for discussion of technology changes in place and in the works by performance audio manufacturers.
angular form factor for the edge diffraction sources can be
written as
FBH��� = FBH = � 4�4� − 2�W
− 2� 1
2.(5)Vanderkooy considers elementary edge sources with an
angular dependence that has phase opposition in the for-
ward direction and is in phase toward the rear. In general,
the Vanderkooy angular form factor for the edge diffrac-
tion sources can be expressed asFV���
=1
2sin��2��2� − �W��
1 − �W �2� 1cos� �
2 − �W ��� − cos� �2 − �W ���
.
(6)The Vanderkooy angular form factor is now developed
for a thin circular baffle. In Fig. 3 M runs along the cir-
cular baffle and represents the edge element. The position
of M is defined by the angle �, which runs from 0 to 2�,
and the radius OM � L. A distant observation point P is
shown in Fig. 3 and the vector OP makes an angle � with
OZ. P� is the projection of P onto the plane X�OZ, and � is
the angle between MO and MP�.For a thin baffle the wedge angle �W � 0° and the
expression for FV(�) reduces to
FV��� = −12 cos���2�
.
(7)
Two cases exist for the shadow and illuminated zones,�� � �� ⇒ FV��� = −
1
2� 21 + cos �
�� � �� ⇒ FV��� =1
2� 21 + cos �
(8)
and since
cos � =MO � MP�MO MP� =
MO2 + MO � OP�MO MP�
Fig. 2. Description of wedge angle �W and shadow and illuminated zones for two kinds of baffles studied.
Fig. 3. Geometry used to calculate angular form factor for
Vanderkooy model.
PAPERS
DISTRIBUTED EDGE DIPOLE (DED) MODEL
J. Audio Eng. Soc., Vol. 52, No. 10, 2004 October
1045
rP distance from edge element to observation pointF(�) angular form factor for edge sources; character-istic of a given model.
The resultant pressure at the observation point is obtainedby adding the driving and edge contributions,
Ptotal�r, �� = Pdrive�r, �� + Pedge�r, ��. (4)
As a basis for comparison, the B&H [2] and Vander-kooy [3] models will be evaluated. It will be seen that theforward sound pressure level (SPL) as a function of fre-quency is described correctly by these two models. How-ever, both of these approaches are inaccurate when itcomes to characterizing the angular SPL dependence, andthis is especially true at � � 90°.Section 1 presents the models from [2] and [3], intro-duces the DED model, and compares all three modelingapproaches. In Section 2 a point source mounted on afinite baffle is analyzed using the DED model and follow-ing this, the case of an extended sound source is consid-ered. In Section 3 the adopted experimental procedure isdescribed, and in Section 4 a detailed comparison of thepredictions of all three models is presented, with experi-mental data for a thin circular baffle. Finally in Section 5a more realistic thick, rectangular boxlike cabinet is mea-sured and compared to the predictions of all three models.
1 DESCRIPTION AND COMPARISON OF THREEMODELING APPROACHES FOR CABINETEDGE DIFFRACTION
Fig. 2 defines the wedge angle �W and the boundarybetween shadow and illuminated zones. The wedge angleis defined by considering a section view along theedge of the baffle. The angle � is the angle neces-sary to turn around the baffle completely, and the wedge
angle is defined as the interior angle of the baffle, thatis, �W � 2� − �.Fig. 2 shows two different baffle types. One is very thinand corresponds to a wedge angle of 0° whereas the otheris boxlike with a wedge angle of 90°. Both baffle typeswill be studied experimentally.The dashed line extending along SP represents the geo-metric shadow boundary. A straight line going from thesound source to an observer situated in the shadow regionwill have to pass through the baffle.
1.1 Driving Pressure in Shadow ZoneFor a finite baffle it is possible to have an observationpoint in the shadow region so the driving pressure must bedefined there. The question that arises is: should the driv-ing pressure for the shadow region be symmetrical to thedriving pressure in the illuminated region, that is, for � >90°, Pdrive(�) � Pdrive(180° − �), or should it be zero andtherefore introduce a discontinuity on the boundary? Dif-ferent driving pressure formulations in the shadow zoneare discussed in the following section for the various mod-eling approaches.
1.2 Description of B&H and Vanderkooy ModelsFor B&H [2] there is no indication as to what the driv-ing pressure should be in the shadow region. Since B&Hdo not consider more than 10° off axis, consequently theirangular form factor for the driving sound pressure is set toKBH(�) � 1 (� � 90°).Vanderkooy [3] assumes that the driving pressure iszero in the shadow region and the sound pressure in thisregion is due to radiation from the baffle edges only. Wethus have KV(�) � 1 for � � 90°, and KV(�) � 0 for � >90° for the Vanderkooy model.
1.2.1 Elementary Edge Diffraction SourcesThe B&H model assumes that each elementary edgeelement is sending out an isotropic spherical wave inphase opposition with the main piston. Therefore the B&H
Fig. 1. Geometry common to all approaches for characterizing baffle edge diffraction.
URBAN ET AL.
PAPERS
J. Audio Eng. Soc., Vol. 52, No. 10, 2004 October
1044
The Distributed Edge Dipole (DED) Model for
Cabinet Diffraction Effects*
M. URBAN, C. HEIL, C. PIGNON, C. COMBET, AND P. BAUMAN, AES Member
L-ACOUSTICS, 91462 Marcoussis, France
A simple model is proposed to account for the effects of cabinet edge diffraction on the
radiated sound field for direct-radiating loudspeaker components when mounted in an en-
closure. The proposed approach is termed the distributed edge dipole (DED) model since it
is developed based on the Kirchhoff approximation using distributed dipoles with their axes
perpendicular to the baffle edge as the elementary diffractive sources. The DED model is first
tested against measurements for a thin circular baffle and then applied to a real-world
loudspeaker that has a thick, rectangular baffle. The forward sound pressure level and the
entire angular domain are investigated, and predictions of the DED model show good agree-
ment with experimental measurements.
0 INTRODUCTION
The frequency response and directivity of a loudspeaker
system depend on the shape of the baffle, the location of
the sound source on the baffle, and the directivity of the
sound source itself. Olson [1] was the first to present ex-
perimental results concerning cabinet edge diffraction, ob-
serving that the radiated sound field depends on the ge-
ometry of the baffle.
Bews and Hawksford (B&H) [2] used the geometric
theory of diffraction to model diffraction due to the baffle
edges. In their approach, sound rays propagate along the
surface of the baffle and are scattered by the edges, pro-
ducing a series of infinitesimal omnidirectional secondary
edge sources.
Vanderkooy [3] derived an angular form factor for the
edge sources using Sommerfeld diffraction theory. The
diffracted pressure is no longer omnidirectional and is
highly dependent on the projected angle of observation.
Vanderkooy’s experimental results concerning the phase
behavior of the edge diffraction wave are highly signifi-
cant and of great interest.
However, current literature concerning the phenomenon
of edge diffraction is somewhat contradictory, and Wright
provides an excellent summary of the major inconsisten-
cies [4]. Wright relies on finite-element analysis to con-
sider cabinet edge diffraction, and his modeling results are
corroborated by practical experiments. Wright’s findings
are very important for the development of the DED model,
as will be discussed in the following.
Fig. 1 shows a representation of the baffle edge diffrac-
tion geometry, which is common to all models outlined in
[4]. The sound pressure from the source Pdrive propagates
to the baffle edges where it energizes a diffractive edge
sound source. The sound pressures of the driving source
and the contribution of the edge sources must be added in
order to determine the sound pressure at a given observa-
tion point. Essentially the problem is to characterize the
radiated sound field due to the edge sources or to deter-
mine an equivalent type of sound source that will account
for edge-related diffraction effects.
In this paper we choose to express the driving sound
pressure for a piston mounted on a finite baffle as follows:
Pdrive(r, �) � K(�) P�baffle(r, �)
(1)
where
P�baffle(r, �) is the sound pressure produced by the piston
when situated on an infinite baffle, K(�) is an angular form
factor for the driving sound pressure, which is character-
istic of a given model, and � is the polar angle between the
direction of observation and the axis of the source.
The elementary pressure induced by the edge sources
can be expressed as
dPedge�r, �� = F��� Pdrive�r = L, � = 90°�e−jkrP
2� rP
dl. (2)
Pedge = o�dPedge
(3)
around edge
where
L distance from piston center to edge element pro-
jected differential length along baffle edge, dl =
L d�
r distance from piston center to observation point
*Manuscript received 2003 October 23; revised 2004 July 9,
July 30, and August 13.
PAPERS
J. Audio Eng. Soc., Vol. 52, No. 10, 2004 October
1043
Proceedings of the Institute of Acoustics
Vol. 33. Pt. 6. 2011
we look at the second image, the red tells us something different. This image is showing delay
impact of the sound. Areas in red are defined as having unaligned sound coverage based on criteria
ignoring sound pressure levels 10db down from a primary source, and more than 30ms in delay
away from the primary source. This image reveals a large problem with the “less is more”
philosophy that maximizes STI, for it also is maximizing the echo/delay problems. A person seated
between arrays would officially have a good STI rating, however the actual sound would have
intelligibility issues due to the distance from each source. The echo and delays caused by the
sound propagation of each array would render the announcer difficult to understand, and bring to
mind an “old stadium” sound, complete with the long echo.
This problem concerning fewer sources vs. echo/delay issue is not new; the most common answer
is to add loudspeaker system elements, thereby creating a more distributed system that will further
optimize SPL while reducing the echo caused by distance between loudspeakers. The images
below show a similar venue, this time with five 12-element line source array systems.
Figure 3: SPL impact, 5 arrays
Figure 4: Delay impact, 5 arrays
As you can see, the top image shows even better sound coverage than before, with more
overlapping and SPL optimization. In fact, to the man sitting between the loudspeakers, this system
would be more intelligible and easier to listen to. However the second image shows us even more
red zones, reflecting substantial delay mismatches from the now five audio sources above the
audience. Based on STI prediction, this solution would score quite poorly, despite being the more
intelligible audio solution. Are line-sources a poor choice for large venues then? Does the width, overlap and even coverage
simply not work when it comes to proper STI and intelligibility? As shown, the overlap is the
problem – as each array propagates into the venue, the audience in being hit from many directions
and multiple sources, creating either the echo problem (example 1), or delay/STI problems
(example 2). So what is the solution?
Proceedings of the Institute of Acoustics
Vol. 33. Pt. 6. 2011
3 INTELLIGIBILTY & STI : “PA” VS. “THE P.A.” As discussed earlier, venues of the past had audio systems designed with one mission in mind – public address. The systems used components to maximize the throw and volume of the announcer, thereby ensuring at least most patrons knew who made that last goal/run/touchdown. Intelligibility was not always considered…. Today we use STiPA (Signal Transmission Index for Public Address) to give an absolute value to the intelligibility of a sound system. Originally developed in the 1970’s as STI, STiPA gives the industry an objective standard with which to predict and measure the ability of a sound system to reproduce speech in a particular acoustic environment. 3.1 Line Source Technology & STiPA: Is STI fooling us? The modern “line-source array” was developed by Christian Heil in 1992, revolutionizing live sound. What was termed as Wavefront Sculpture Technology® allowed the loudspeakers to provide high quality, full bandwidth, high volume audio coverage evenly from the front to rear of a venue, even a very large one. Over time, this technology has grown throughout the industry and made its way into many installed sound systems. It is common to see the “line array bananas” hanging down not simply at concerts, but also in performance venues of every type, including large athletic arenas and stadiums. The wide pattern coverage and ability to project the sound evenly from the lower to upper decks seems to be a perfect match to a stadium. However this the match is not always made in heaven…
Figure 1: SPL impact, 3 arrays
Figure 2: Delay impact, 3 arrays In these images, we see a typical stadium side audience area being covered by three 12-element line source array systems. The dots shown in yellow on the top image indicate the sound pressure impact zones, with open circles representing a “-3db” down point for the loudspeaker. As you can see, there is a very even and consistent coverage across the seating area. The system as designed would create even SPL and an optimized STI rating based on the definitions of STI. However, when
Proceedings of the Institute of Acoustics
Vol. 33. Pt. 6. 2011
PERFORMANCE AUDIO + INTELLIGIBILITY + EVAC = ??
A LOUDSPEAKER MANUFACTURER’S TAKE
A. Nagel L-ACOUSTICS, Marcoussis, France
C. Montrezor L-ACOUSTICS, Marcoussis, France
G. LeNost L-ACOUSTICS, London, United Kingdom
D. Yates Vanguardia Consulting, United Kingdom
1 INTRODUCTION
Entertainment, worship, and sporting venues around the world continue to grow in number and
capacity. With these increases comes a demand for both high quality and highly intelligible sound
reproduction for activities during and outside of the event. Also with this increase, the safe and
controlled evacuation of patrons has become of equal importance to the quality of the sound,
leaving operators, engineers, talent and manufacturers to find a balance together. Size isn’t all that
matters, however; legislation moves onward in both the European Union and the United States,
requiring audio system manufacturers to not just conform but lead the way in integrating their
performance sound equipment with voice alarm and annunciator systems for emergency
evacuation. It’s no longer just stadiums; we must reevaluate systems for even the smaller to mid-
sized theatres, arenas, churches, and conference centers. Moreover, as “sports-tainment”
continues to grow in popularity, operators require the highest quality sound for the patron
experience, eliminating the “echo” of horn & bin systems to provide full range, accurate, if not
concert quality music reproduction for the event. So what can a manufacturer of audio equipment
do? Using several case studies, L-ACOUSTICS will present working solutions to balancing high
performance audio, STI requirements, and evacuation system integration through the use of line
source array technology, loudspeaker monitoring, smart controller amplifiers, and network control
and switching. This will serve as a launch pad for discussion of technology changes in place and in
the works by performance audio manufacturers, through presentation, live equipment
demonstration, and roundtable discussion within the session attendees.
2 THE ISSUE OF SOUND: “LET’S GET ROCKIN’, BABY”
In our fast-paced, non-stop action world, there are few places that are not bombarded by sound, be
it environmental that simply occurs around us, or targeted specifically at us to get our attention.
Sporting events are no longer immune to this barrage, where the “PA” is no longer simply an
announcement system, but rather the deliverer of an aural experience for the spectators and the
players themselves.
Gone are the days of a tinny national anthem shrieking through a few stadium horns and echoing
around the grandstand. With the continued rise in ticket prices, spectators are demanding a full on
sports-tainment experience, with quality music pumping through the system before, after, and even
during play. Venue operators and professional teams are scrambling to give the experience, trying
to lure fans in, and keep them excited for the entire event – for value added to the high priced ticket,
or to get the concessions flowing.
30
ENvIRONMENTAl CREDENTIAlS
GREEN SOUND SySTEMS
• L-ACOUSTICS line arrays have replaced the wall of sound from the ’80s
• acoustic energy focused on the audience, less noise pollution
• minimized acoustical interferences and electrical energy waste
MODERN ElECTRONICS
• highly efficient power supplies and sophisticated system control
• high-powered Class D amplification of LA8 electronic
• elevated energy efficiency close to 85% (versus 50% in the ’80s)
MANUFACTURING, STORAGE AND SUbCONTRACTING
Assembly plants, storage, and R&D departments are all local. 100% of our suppliers and subcontractors are located in France or europe.
• SIMEA joinery: Alsace, France
• electronic assembly: Germany
• assembly of the loudspeakers: Marcoussis, France
• origin of speaker parts: European region
• wood: from renewable forests in Finland and Lithuania
RECyClING
• wooden pallet recycling
• paper and cardboard recycling: systematically sorted at every workstation and collected by specialized companies
• recycling of computer equipment and consumables
lOUDSPEAKER COMPONENTS
• all metallic parts used in the loudspeakers are recyclable
• wood cabinets: no toxic product rejects
• wood: L-ACOUSTICS participates in a reforestation program for the Baltic area
PHOTO CREDITS
Cover page Hollywood Bowl, Ramesh Shihora (Yahoo! Flickr) Guangzhou Opera House, © HUFTON + CROW Copenhagen Opera House, Lars Schmidt
Page 4 Shanghai Oriental Arts Centre
Page 8 Hollywood Bowl, Ramesh Shihora (Yahoo! Flickr)
Page 9 Hollywood Bowl - Adam Latham
Page 10-11 Bamboo Nightclub Grammy Award-winner Alejandro Sanz performing at Bamboo Miami
Page 12-13 Danish Radio Concert Hall - Bjarne Bergius Hermansen
Page 16-17 The National Theatre
Page 18-19 Page 18 - Chongqing Grand Theatre, © HGEsch, Hennef And top of page 19 - Chongqing Grand Theatre, © HGEsch, Hennef
Page 22 Guangzhou Opera House, © HUFTON + CROW
Page 23 Guangzhou Opera House
Page 24-25 © Pierre-Emmanuel Rastoin/Salle Pleyel
Page 26 Copenhagen Opera House, Copenhagen – Denmark Suzhou Science and Cultural Centre, Suzhou - China
Page 27 Opéra Royal de Wallonie, Liège - Belgium Jacky Croisier Salle Raoul-Jobin, Quebec
www.l-acoustics.com
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