l-acoustics sound solutions: sports facilities
PHOTOS CREDITS COVER BOTTOM LEFT: Spaladium Arena, Croatia, Dicroic BOTTOM RIGHT: Shirlaine Forrest/Getty Images Entertainment/Getty Images
introduction 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 energizing international events ranging from the Hollywood Bowl to the Olympics ceremonies, the FIFA World Cup and countless facilities worldwide.
A partner for sports facilities 5
As sports and entertainment business continue to converge, sports facilities are increasingly required to provide a level of excellence in sound reproduction equal to a live concert-like experience, by fans and advertisers alike. This sports facilities brochure presents a select number of sports facility 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 sound system sports facility project presents its own unique set of objectives, challenges and constraints. With L-ACOUSTICS, we always find the solution.
...through to integration 15 Meeting short deadlines - Rogers Arena Scoreboard remote coverage - Spaladium Arena
We look forward to delivering The Best Sound to your fans in fields, courts, and ice rinks across the planet!
Cédric Montrezor Director of Application, Install
rom the Design phase... f 7 Improving intelligibility - Freeman Coliseum Optimizing coverage - rewirpowerStadion Reducing echoes - Nagai Stadium
. ..and beyond 21 Spectator immersion - Tampa Bay Times Forum Multi-use facility - BYU Marriott Center References Sports facilities portfolio White papers
26
Environmental Credentials
30
“I Think Almost everyone commented on the tremendous atmosphere in the stadium and the l-acoustics audio system certainly made a significant contribution to that.� Roland Hemming, London Organising Committee of the Olympic and Paralympic, Games (LOCOG) Venue Technical Manager - Audio, UK
L-ACOUSTICS was selected to electrify the London 2012 Olympic Stadium with a capacity of 80,000 for the Opening and Closing Ceremonies of the Olympics and Paralympics as well as for every single athletic event held within the Olympic Stadium for over a 120 day period in total.
a partner for sports facilities
Delivering a concert sound experience for every fan With a good sound system, everyone enjoys the show. L-ACOUSTICS’ number one goal is to create an unprecedented sonic experience for spectators, with easily reconfigurable and widely accepted sound systems. Combining breathtakingly high-impact sound reinforcement with stunningly pristine intelligibility, our systems deliver a truly immersive experience for sports fans as well as enhanced results for advertising partners. Our high-quality systems allow sports facilities to become truly multi-purpose venues, with the potential to create or enhance additional revenue streams.
How is this achievement possible? L-ACOUSTICS has been designing reference line array systems for more than 20 years. Our exclusive technologies, providing enhanced directivity control, allow L-ACOUSTICS to: • provide consistent Sound Pressure Level, and sonic experience, to every audience member • enhance the intelligibility of the system, ideal for spoken word messages • provide enhanced zoning capabilities, optimizing acoustics and offering energy savings and flexibility in your system set-up L-ACOUSTICS speakers focus all of their sonic energy on a particular segment of the audience. This allows an exceptionally coherent sonic signature in very long throw applications, beyond the limits of other systems.
5
“when looking at a large venue sound system, predictability is essential.� Charlie Lawson, formerly Director of Audio, AVI-SPL, USA
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.
from the Design phase...
Powerful acoustic simulation tools
No custom mechanical design
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.
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 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.
SOUNDVISION allows sound designers to visually design and optimize the performance of L-ACOUSTICS sound systems in individual sports facilities. This intuitive ‘what you see is what you get’ visual approach provides the greatest speed and accuracy in:
With L-ACOUSTICS, the design phase of a sound system for sports facilities brings an unprecedented level of predictability alongside the maximum efficiency.
• predicting and adjusting the sound design according to the exact geometry of the facility • providing equipment options to balance between Sound Pressure Level and budget
* L-ACOUSTICS can provide electro-acoustic modules to offer compatibility with third party software such as EASE, CATT, LARA and ODEON.
7
Improving intelligibility FREEMAN COLISEUM “I was told that an L-ACOUSTICS solution would sound at least ten times better than what we had been using. Once the team had performed the installation, I had to admit that they were right. The sound is absolutely spectacular.” Derrick Howard, Executive Director Freeman Coliseum
Location Texas, USA Capacity 9 800 (Basketball) 11 700 (Boxing) equipment list 8 x 5 ARCS FOCUS 8 x 2 SB18i 6 x LA8 2 x LA4
8
from the Design phase... Challenge The sound system of San Antonio’s Freeman Coliseum is frequently called upon to provide speech reinforcement for graduation ceremonies, corporate functions and other similar events. As part of a multi-year initiative to update the venue, Bexar County and the facility’s management team decided to replace the old system to improve intelligibility. solution The decision was made to replace the sound system entirely. The improved sound could be heard and measured with an onsite evaluation. It was also the most cost-effective solution. An L-ACOUSTICS WST constant curvature line source was chosen for its high control of directivity preventing the spill of acoustic energy onto reflective surfaces.
results After system commissioning, the intelligibility of the hall measured (according to the Speech Transmission Index value) reached between 0.70 to 0.82 per cluster, with an overall value of around 0.60, greatly improving the overall intelligibility of the system. These measurements were identical to those predicted by the acoustical simulation software.
9
OPTIMIzing COVERAGE rewirpowerstaDion “The L-ACOUSTICS system of distributed coaxial enclosures covers the stadium with breathtaking sound and even SPL.” Guido Kacher, www.soniek.com, Bamberg
Location Bochum, Germany Capacity 29,448 equipment list 40 x MTD112b 22 x MTD115b
10
from the Design phase... Challenge Prior to its renovation for the 2006 Soccer World Cup, rewirpowerSTADION was equipped with a 100V traditional sound system which delivered an uneven audience coverage and reduced bandwidth. As a result, the impact of music and advertising announcements on spectators were limited, and many spectators were “left out� of the show in zones where sound coverage was poor. solution The sound system (designed by the consultant) was based on a distributed L-ACOUSTICS coaxial system. This solution was technically validated by the client during a shootout session. A total of 40 MTD112b and 22 MTD115b were deployed to ensure the complete coverage of the audience in both the upper and lower tiers, respectively.
results
[dBV/dBV]
The new system measurements showed that a smooth SPL coverage within +/- 3dB was achieved throughout the audience and a bandwidth of 80 Hz to 16 KHz, at an exceptional price/performance ratio.
Smoothed Frequency Response Magnitude WinMLS Beta
-30 -35 -40 -45 -50 -55 -60 -65 -70 -75 -80 -85 -90 -95 -100 -105 -100 -115 -120 -125 -130
MTD112b
Measured - 14:47:27, 24 Aug 2009 Plotted - 16:24:58, 03 Oct 2012 Name: rewirpowerStadion
10
100
Frequency [Hz]
1000
10 000
11
reducing echoes nagai stadium “The L-ACOUSTICS system delivers outstanding performance in terms of intelligibility, SPL and coverage.” Yoshiteru Mimura, ARCHITO Co, Japan
Location Osaka, Japan Capacity 50,000 equipment list 2 x 12 dVDOSC 1 x 8 dVSUB 52 x ARCS 19 x MTD 115b
12
from the Design phase... Challenge A new PA system was required to reproduce music programs at the Nagai Stadium with an extended frequency range and a high SPL. The consultant had to find a balance between preserving the musicality of the system and maintaining the intelligibility necessary for announcements. Echoes created by the selected multi-cluster approach had to be minimized. solution The distributed design was deployed with ARCS constant curvature enclosures arranged in horizontal arrays (due to the fact that widely distributed vertical arrays tend to generate echoes). This WST system features a razor sharp directivity in the horizontal plane, thus creating audience sectors acoustically distinct from each other.
results At a throw distance of 50m, the ARCS system distributed in arrays of 3-4 enclosures yields a consistent, cost effective coverage with early and late interferences reduced to minimum. The system combines intelligibility, musicality and clarity.
Echogram SPL Cluster #1
Audience ambient noise
Adjacent cluster
t
13
“Denis Hainaut, The director of Ice sports for the Vancouver winter olympics Organizing commitee listened for a while, looked at me and said, ‘I’ve never heard anything sound so good in an arena’.” John Riley, Chief Audio Technician, Canucks Sports and Entertainment, Canada
Installation of the dV-DOSC system at Tampa Bay Times Forum, home of the Tampa Bay Lightning. The integration phase of an L-ACOUSTICS sound system can be completed in three days (rigging , cabling, amp racks and flying arrays) to meet busy sports facility calendars, with dramatic results.
...through to integration
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 ensure the 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.
ensuring that the system will work at its best. L-ACOUSTICS clients’ benefit from dedicated L-ACOUSTICS manufacturer support. Sports facilities 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. 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.
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
System Integrator CERTIFIED PROVIDER
15
meeting short deadlines rogers arena “The scheduling for the sound upgrade was complicated by a ten day Janet Jackson tour event. We had a very small window to install the system, and it went like clockwork.� John Riley, Chief Audio Technician, Canucks Sports and Entertainment, Canada
Location Vancouver, Canada Capacity 18,890 equipment list 6 x 13 dV-DOSC 6 x 2 dV-SUB 2 x 8 SB28 23 x LA8
16
...through to integration Challenge The installation at Rogers Arena needed to be set up within an extremely tight deadline, just prior to the start of Vancouver’s NHL season home opener. It also had to be agile enough to cover a planned architectural expansion to host the forthcoming 2010 Winter Olympics Ice Hockey games.
solution SOUNDVISION allowed the system rigging to be implemented and fully documented ahead of time. At the same time the system was zoned to provide coverage for the new press box seating and Olympic expansion zones.
results System tuning and alignment using the advanced preset library was incredibly fast using LA8 controlled amplifiers and LA NETWORK MANAGER software. The System (rigging, cabling, amp racks) was installed over a three day period. System commissioning on day four was completed in time for the NHL Season opener, and the results were dramatic. The new system provided a high level of impact suitable for sports as well as multi-use events.
17
scoreboard remote coverage Spaladium arena “The audience and field are 100% covered and speech intelligibility is excellent. At all measuring points, the PEAK SPL was 111 dB, within 1 dB. I believe we have designed the best arena sound system in Croatia.� Slaven Tahirbegovic, Dicroic, Croatia
Location Split, Croatia Capacity 12,000 equipment list (4+1) x 9 dV-DOSC 4 x 2 dV-SUB
18
...through to integration Challenge Opened in time for the 2009 Handball World Championships, the Spaladium Arena had to meet a tight installation budget. The sound system was needed to be located in a single location in order to optimize the building infrastructure in terms of signal distribution, mechanical rigging and electrical power. This design called for a compact, lightweight central, long-throw scoreboard sound system with high SPL and intelligibility. solution The sound system is based on four cardinal arrays (E-W-N-S) of 9 dV-DOSC and 2 dV-SUBS (delivering LF frequency extension) flown around the scoreboard. An additional array of 9 dVDOSC enclosures is rigged underneath the LED cube, covering the playing field. The amplified controllers are located in the grill, just above the PA. The weight does not exceed 400 kg per cluster. results The long throw capability of the L-ACOUSTICS WST variable curvature system allows the sound system to deliver a peak SPL of 111 dB on average across the entire audience for a bandwidth of 50 to 20 KHz. This is perfectly executed, with the audience areas and areas of play covered 100%, and excellent speech intelligibility in both areas.
19
spectator immersion tampa bay times forum “I pointed out the difference in the pattern control between L-ACOUSTICS and other manufacturers. Keeping the audio out of the broadcast and ice rink mics on the glass was essential to achieve gain beforefeedback.� Charlie Lawson, formely Director of Audio, AVI-SPL, USA
Location Florida, USA Capacity 20,000 equipment list 66 x dV-DOSC 12 x dV-SUB 8 x SB218 4 x ARCS 36 x LA48a
20
...and beyond Challenge To engage spectators more closely in the action of the games on the ice rink at Tampa Bay Times Forum, reproducing the sound of the stick hitting the puck. It had to overcome the difficulty of the relationship between the placement of microphones on the glass which needs to pick up the sounds of the game but not the PA system.
solution dV-DOSC and ARCS deployment ensured accurate coverage from the glass up to the top tier seating, and razor sharp vertical control to fulfill the design objective. ARCS were used under the scoreboard to supply high impact sound to the players on the ice surface. DV-SUB was added to the 6 main arrays with 2 x 4 SB218 additional subwoofers for enhanced low frequency extension and impact. results The system was implemented following the SOUNDVISION model. It produced extremely even coverage and the performance upgrade overall was dramatic. No delays were required, and the system was completely turnkey.
21
multi-use facility byu marriott center “The marriott center hosts something different every day, so we needed a very versatile system that could handle all those different types of events.� Brad Streeter, Multimedia Engineer & Installation Project Manager, BYU, USA
Location Utah, USA Capacity 20,900 equipment list 32 x KARA 32 x KARAi 90 x KIVA 18 x KILO 8 x SB18 8 x SB18i 16 x LA8 16 x LA4
22
...and beyond Challenge The BYU Marriott Center is a multi-use facility hosting NCAA Division 1 Basketball, convocations and devotional services and fine arts department productions. The sound system had to be fully configurable both mechanically and in terms of DSP control over a network connection.
solution The system design provided 32 KARA elements for the flexible arrays, and 32 KARAi elements for the fixed arrays. Up to 32 elements can be arrayed for proscenium stage setup in 180 degree coverage, or split into smaller arrays as needed.
results The system is extremely accurate. Using the KARA and KARAi offers a complete flexible multiuse system which is completely configurable. The entire top tier can be zoned on/off using the KIVA system and additional KIVA arrays in waterfall configuration offering complete, effective floor coverage.
23
“I have to think very hard to remember the occasions where I have experienced component failure in an L-ACOUSTICS system. With over 450 loudspeaker products directly exposed to the elements for over four months, the system reliability was key for London 2012.� Scott Willsallen, Auditoria Pty Ltd, London 2012, Ceremonies Audio Systems Designer, Australia
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.
...and beyond
REVENUE GENERATION A high performance and flexible sound system contributes to revenue generation. Offering a high impact and immersive experience attracts more spectators, while providing high quality speech intelligibility meets advertiser demands. In addition, a rider-friendly sound system helps facilities to attract high profile events. Finally, the ability of L-ACOUSTICS systems to be reconfigured enables multi-use facilities to diversify their income streams.
LONG TERM INVESTMENT L-ACOUSTICS systems boast an exceptional durability. For over 30 years L-ACOUSTICS systems have been used as touring and festival systems on a daily basis in challenging outdoor environments. All of our installation products meet the IP45 rating. Our earliest sport facilities clients have been enjoying their MTD 115 sound system for more than fifteen years with MTD 115 continuing to deliver outstanding performance today. All our systems come with a warranty of five years.
25
Jobing.com Arena
USA, Glendale - AZ
Nagai Stadium
Japan, Osaka
Olympiahalle
Germany, Munich
Kantonsschule Gymnasium Switzerland, St Gallen
Tampa Bay Times Forum
USA, Tampa - FL
KB Indoor Sports Stadium Denmark, Copenhagen
Arena Žatika Chukyo Racecourse of Keiba Douai Racecourse Esbjerg Gymnasium
Croatia, PoreÄ? Japan, Keiba France, Douai Denmark, Esbjerg
Meriadeck Ice Rink
France, Bordeaux
Nakayama Race Course
Japan, Nakayama
Omnisport Hall of Theolade Ostseestadion
Germany, Rostock
Rogers Arena
Canada, Vancouver
Piscine du Stade Louis II
Monaco, Monte-Carlo
Hellerup Gymnasium
Denmark, Hellerup
Prima Skonto Sport Hall
Estonia, Riga
Ice Hockey Hall
Russia, Kondupoga
rewirpowerstadion
Diocric
26
France, Guyana
Germany, Bochum
references
sports facilities portfolio
Spaladium Arena Sports Arena Sports Hall Landhaus
Croatia, Split Sweden, Växjö Switzerland, Teufen
Chicago State University Sport Club Pohoda
USA, Chicago - IL Czech Republic, Podoha
Telenor Arena
Norway, Oslo
Sports Palace
Belarus, Minsk
Sport Venue of Kemerovo
Russia, Kemerovo
Tikkurila Arena
Finland, Vantaa
BYU Marriott Center
USA, Provo - UT
Vikingskipet Olympic Stadium Minsk-Arena Project
Norway, Hamar EWS Arena Belarus, Minsk
Halle des Sports
France, Niort
Roller Skate Hall
Switzerland, Basel
Poprad Aquapark
VfL Bochum 1848
Germany, Göppingen
For more reference information please visit: www.l-acoustics.com/installations www.l-acoustics.com/picture-gallery
Slovakia, Poprad
Dietmar Strauß
Deward Timothy
27
Sound Field Radiated By Arrayed Multiple Sound Sources AES 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
___
________
________
________
________
Socie eering HEIL, URBAN AND BAUMAN Audio Engin
ty
HEIL, URBAN
n Paper
AND BAUMAN
Technology AES Convention Paper #5488 - 111th AES Convention - 2001 We introduce Fresnel’s ideas in optics to the field of acoustics. Fresnel analysis provides an effective, intuitive approach to the understanding Conventio
WAVEFRONT SCULPTURE TECHNOLOGY
2 THE FRESNEL APPROAC SOURCE
WAVEFRO NT SCULPTUR E TECHNOLO
fronts propagate with 3 dB attenuation H FOR A ion The per doubling CONTINUO of fact distance Convent that light We also demonstrated (cylindrical wave propagation) USa LINE in [1] that USA is a wave line array of sources, each of an in the NY, isophasic far field the 111thwhereas there is 6 n a flat isophase wave d at per themimplies dB attenuation radiating interference doubling New front, will produce secondary point of waveand extended of York, distance (spherical consideratio Presente or lobes light view. phenomena propagation).erIt 21–24 not source greateristhan –12 These interference is to be noted that usual concepts but Fresnel, request corrections, when to the main lobe in the looked atdB with respect sending ofediting, directivity, . variations polar diagrams and lobes only make in 1819, by far field and from patterns SPL a given not 2001 Septemb greater described be obtained sense in without than ± 3 dB within the near are not easy the farthese field patterns. may manuscript, (this is a also see www.aes.org
GY
developed in appendix 1).advance way the papers Fresnel's field region, provided to predict that: , USA; semi-quantit into fictitious idea wasfrom to author's 10165-2520 to partition from the for the contents. Additional ♦ Either zonespermission the sumthe direct picture radiating areas of theatively flat, individual made New York zoneswithout y are classified up of elementary covers been reproduced Considering New York, light source next and line than 80% ofmain the observer according more no responsibilit withis discontinuities, not permitted paper has frame of the array, i.e., the 42 Street,source we also takesdescribed lightthe vertical to theirradiating thereof, in such a a East progressively target This conventionBoard. The AES chaotic arrival area sources. The behavior of the the Society, 60 way observer sound field as or any portion the first zone time differences these paper, (within a ♦ thatOr by the Review to Audio Engineering zone This between the individual this discontinuities become progressively larger. to fraction of the spacing appears n ofconfirmed consists sound sources is wasof in 1997 [3] when Smith, working the than 1/(6F) , i.e.,inλ/2. phase to smaller Reproductio Society. and remittance on observer an array position, length λ). of 23 elementary sources wave reserved. The next two that are form Engineering loudspeakers, discovered that 7 dB SPL variations respect but are These All rights over 1 to of WST Criteria which, in foot collectivelyrequirements the Audio in-phasethe basis thewas a common feature in the near field. first turn, define in phase for at the coupling Journal of that the fraction Smith the effective cosine zone, and so on. A conditions of multiple sound opposition weighting approaches in order to diminish tried raised sources. the precise following sections, with and λ/2.7 this chaotic we will derive these results SPLforand of wave length is Inmore analysis was somewhat successful, but it is not λ/2 using the a Fresnel for a 2-dimension approach along shows possible to further have, atdetails). with further results that are useful the same 1-dimensional source time, raised cosine weighting for for line source al source acoustical predictions. (please the near field and Bessel see appendix weighting for the far field. In [1] we showed We willa way to 2 for apply Fresnel’s minimize these effects is to build a quasi-continuousthat sources. N Figure 1 displays a cut view of the radiated sound field. The SPL is wave Let front. BAUMA us considerconcepts significant to theonly in the dotted zone (ABCD + cone beyond isophasic sound PAULline field of extended BC). A The location of the border between a detailed HEIL, perfectlydescription more source. To first IAN the near front is deferred to Section 4.Figure 4: field andwill the far flat, field determine perform is a key parameter that , CHRIST The observer describes the wave field.draw how this continuous and call dB the with respect to STICS Let usspheres continuous L URBAN distance from the array correspondin O, is no longer centered a given to this border. We L-ACOU incremented MARCE France will make the on the listener listener position,wave facing the 91400 approximation that if F is the frequency by steps view). There g Fresnel zones position equalsthen line source. of λ/2 (see in kHz La-Ville, are the λ=1/(3F) whose radii we tangential where λ is the other off-axis.is no dominant zone shown on the figures to the understanding The wavelength in metres. Considering the Gometzlistener. 3 and distance are approach and for a flat, and individual left part (front continuous 4). Basically that intuitive sources The line source of height H that is radiating separates Wavefront first radius of sound effective, two zones cancel an wavefront, cases can a flatprovides isophasic coupling is termed the line source be observed: we demonstrated in [1] that a reasonable Moving the each and the the effective the basis of what 1. A dominant average Fresnel analysis offorthe different form the criteria source and observation point possible expressions zone of acoustics. for B establishing appears: Theeither obtained using to a few outercriteria geometric, to the field the roaddto The derived zones are can picture of repeating the exercise, numerical locations in optics or Fresnel opens calculations size is approximate alternatively applications. is: around the the sound polar plot ABSTRACT Fresnel’s ideas and thus frequency. an SPL reinforcement field radiated we can get a good line ly equal and of multiple then consider While in-phase We introduceinterference phenomena and out-of-phase in sound array qualitative by the line they an geometry level only (SPL). cancel each horn-loaded . Their others. 3 of complex a given audience theloudspeaker, source at largest, dominant 1 pressure We assume trapezoidal other out. to the of a given Note that a single d B = F H 2 1 − sound Typically, arrayszone We can coverage that this dominant according SPL radiated the Fresnel so simple. Technology. characterize andcoverage notthe 2 isby single frequency. neglect all representatio fan-shapedzoneand Sculpture 2 at the 92nd where line in is vertical representativ zones loudspeakers source. ns of figures 3sound FH it is seen The effects horizontal are assembled axis listener This is illustrated overlapping e of the presented that 3 and fornominal of this of changing loudspeakers position are ION by the an observer to reduce intensity directivity of the preprintthe conclusions corresponds frequency 4 are at a Figure 3 since the in sound shown in and in an attempt facing first 0 INTRODUCT angles zone.determined analysis the linethe Figure 5. and the onis a continuation[1]. Revisiting roughlyHowever, each enclosureinterference. dB and source H are in meters, to the frequency, This paper mathematical F is in kHz. in 1992 where approach angles of not couplethe varies with sounddoradiated on detailed more qualitative cause destructive of the AES Convention boththe 2. No thatdominant loudspeakers were based loudspeakers with by present a understanding There are three we now article, which zoneby the arrayed things sources. a better that changes of the individual tosound note about radiated appears this methods, that in theFigure of formula:wavesto radiated discreteindicates 1) enables numerical The root factor pattern1: observer in interference an array illustratesnearthe that in arraying resulting Fresnel analysis position.Radiated and almost field define how for position. linethere is no the case involved based on that frequencies from SPL no coherently, of a line lower Referring source sound than for apart is AD of height H. In the near field, the listener continuous Hence a 4 m high array willand an off-axis phenomena establish criteria to create a1/(3H). to 3 speakers), the physical we immediately in the far SPL decreases observer. frequency radiate to be the (column asfigure dB per 4, isdoubling fieldout analysis, mode of distance, whereas in for problem this be assembled criteria turn frequencies less than 80 Hz. also From this array systems field, the another sources can 2) For these decreases as 6whoseper doubling of distance. the far early line abovein [1]. Wethe near field extension array,frequencies directivity, SPL a flat discrete sound main beamwidth dB criteria developed 1/(3H) is almost with Considering linear with frequency. of the vertical outside the can be improved define other were originally source. Considering narrowing of secondary lobesIt should Bessel source and free of destructive level. This be noted those which 3) Theline that different as authors have come up with various ison the dimension for example, same as curvature dependence the on-axis appearance is notbelinear the case the array, H of the array field that fordistance: expressions schemes, forSPL a variable as high as shading but quadratic. the and, border a wave region for of the consider SPL can or number of coverage to produce is a reduced tapering as the inverse d = 3H are optimum required various Smith [3] open-air that Bthe main drawback over a predefined that decreasescollective criteria All of this enough for dbeing intensity indicates that the near field can extend weighting. The interference it was shown B = H/π Rathe [4] quite far away. area. These wave field For Criteria. 1 weighting, This is far from example, well as a audience a 5.4(WST) dB = maximum of (H , λ/6) of Bessel five [2]. over the Beranek [5] Technology m high flat line source array will have a near a field extending distance Most of these expressionstoomit Sculpture sources was as far as 88 meters at 2 kHz. . the frequency dependency and are - A REVIEW array produce termed Wavefront areas in incorrect performances first a RADIATION line source the size dependence. of a concerning Figure 2 illustrates the SOURCE cover large audienceand more Considering we the solution variationasofpossible. SOUND to source, border distance of more and far field divergence angle with advocated many 1 MULTIPLE more sound power implies the use phase) line In [1] we that is as continuous distinct frequency for for a flat (constant linespatially source array of Figure= 5.4 m. is to configure applications The need required wave front and isophasicfield exhibits two near field, wave height 5: practice achieve the sound reinforcement The effect In the A common flat, continuousthat the sound in order to far field. of changing or clusters sound sources. demonstrated near field and the frequency in arrays the and listener loudspeakers regions: As the frequency of Lposition. are trademarks is decreased, so that a and WST larger portion the Technology dominant of the line size of the Fresnel Sculpture zone. Conversely, 1 source is zone Wavefront portion of located within grows as the frequency the line source ACOUSTICS If the frequency is located increases, the first inside the a reduced is held constant Figure 3: to the array, first dominant and the less of the Observer dominant zone. line source listener position facing the zone due is closer circles are is located to away, the line source. entire line the increased curvature. within On the right increasing drawn centered source falls As we movethe first part on the within the (side view), observer 3 EFFECTS source AB by steps of λ/2. first dominant further The pattern O, with is shown OF DISCONTIN zone. Fresnel zones. radii ARRAYS on the left of intersections part (front UITIES on the In the real view). These ON LINE SOURCE define the assembly world, a line source of separate array results transducers loudspeaker from the vertical enclosures. thicknesses. do not touch each Figure 2: other because The radiating Assuming flat wave Representation of the variation of border that each of the enclosure front, the distance and far field divergence angle thisforsection, line source transducer originally with frequency array of height 5.4 metres. wall a flat line array is oursource radiates goal is to analyze no longer continuous. a AES 111 TH the In differences CONVENTI versus a ON, NEW YORK, NY, AES 111TH CONVENTION, NEW USA, YORK, NY, USA, 2001 SEPTEMBER 21–24 2001 SEPTEMBE R 21–24 2
___
________
________
________
________
t Sculpture
Wavefron
(
y
Technolog
)
3
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 Technology AES Journal - Vol. 51, n°10 - 2003 The 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 soundreinforcement applications. The derived criteria from the basis of what is termed Wavefront Sculpture Technology.
references white papers
PAPERS
URBAN ET AL.
PAPERS
angular form factor for written
the edge for r distance from edge element to observationas elangle diffraction point ) Mod sources angle is defined as the interior F( ) angular form factor for edge can beof the baffle, that sources; characterle (DED is, 2 − . Two cases istic of aDipo given model. exist for F Fig. the shadow 4 2 shows two different baffle types. One is very thin and illuminate 1 ibuted Edge action Effects* = F = and 4 −corresponds d zones, 2 − 2 to . a wedge angle of 0° whereas the other The Distr Diffr The resultant is boxlike with 2a wedge angle of 90°. pressure at the observation point Vanderko (5) Both baffle types is obtained 1 oy Member ⇒ F Cabinet by adding the driving and edge contributions, 2 willelementar =− be studied experimentally. angular , AESconsiders BAUMANdependenc y P
PAPERS
The Distributed
DISTRIBUTE
D EDGE DIPOLE
W
BH
(DED) MODEL
BH
W
V
2 edge sources e that 1 + cos The dashed , AND P. ward direction has SP represents the geowith an phaseline extending along , C. COMBET the Vanderko and ismetric shadow opposition in phase in straight the for- line going C. PIGNON France towardboundary. A oy angular from⇒the + Pedge r,is, C. HEIL, Ptotal r, = Pdrive r, Marcouss sound source to anthe rear. In situated . tion sources (4) FV = 1 general,in the shadow region 2 the form factor for observer M. URBAN, can be TICS, 91462 on expressed will have to pass through the edge L-ACOUS 2 thediffracbaffle. edge diffraction as 1 + cos in an enof cabinet FVwhen mounted since it As a basis for comparison, for the effects the B&H s[2] model and Vander1.1 Driving Pressure in Shadow and since r component to account kooy Zone dipole (DED) with their axes [3] models proposed loudspeake will be evaluated. edge ting It will be seen 1 sin model is dipoles the is firstFor a finite baffle it is possible 2that 2 model the distributed distributed A simple forward for direct-radia sound pressure − W to have an observation DED level (SPL) as a=function ion using sound field approach is termed 2 The1 − ofto frepoint in the shadow region so the driving sources. a real-world radiated approximat quency is described MO be proposed 1 pressure correctlydiffractive applied HowMP MO 2 by these cos = must W 2 and the Kirchhoff elementary thenmodels. level defined there. on theboth closure. The basedever, and two The question that arises is: should + MO OP as the baffleare of approaches MO the cos drivsound pressure inaccurate MP = is developedlar to the baffle edgefor these when good agree. ing pressure a thin circular The forward region model show it comes tontscharacterizing MO MP 2 − W for−the be symmetrical to the cosshadow baffle. the angular the DED perpendicu dependence, and measureme driving pressure rectangular predictions ofSPL in the2 illuminated − this aisthick, especially region, that is, for > tested against true , and at 90°. r that has are investigated 90°, Pdrive( ) Pdrive(180°W − ), or The Vanderko loudspeake domain Section 1 presents nts. the models from [2] (6) should it be zero and oy angular [3], intromeasureme for a and therefore althe introduce entire angular a thin discontinuity duces form DED on the boundary? Difcircular model, and compares all three modeling experiment factor is ment with now developed driving pressure In Fig. approaches. In Section 2 a point cular baffle and baffle.ferent formulations in the shadow zone s 3 M runs source represents mounted on of M is arethe discussed in propagate the along following finite baffle is analyzed using the DED drive defined by a the section for the various modedgePelement. source edgethe cirand followthe angle andmodel from eling ,approaches. the radius a diffractiveThe position ing this, the case of an extended sound pressure which OM itL.energizes source sound source runs is considshown The from driving [4]. A distant inedges ered. In Section 3 the adopted experimental 0 in to 2 , Fig. 3where of the observatio andisthe added 1.2 Description pressures OZ.baffle vector n B&H to the P isprocedure must be of point and Vanderkooy Models sound described, and in Section 4 a detailed the OP makes The projection sources comparison observa-P is the source. an angle the edge of P For given angle between a[2] there nofofthe iszeno the ontoB&H predictions of all three models indication as to what the driver issound with theatplane presented, pressure CTION with experiX OZ, sound Forcontributio anding pressure and the characteri theMO a thin baffle MP . be in mental data of aaloudspeak andthe is shadow region. Since B&H is to should 0 INTRODU of baffle. thin circular deterFinally and directivity forthe problem in Section 5the to determine location expression or tothan the wedge do not consider order response a more sourcesmore 10° off axis, consequently their realistic thick, rectangular for F ( ) angle Essentially of the of the baffle, boxlike cabinet point. isVmea-reduces to the edgeform factor The frequencyon the shapesured will W tion directivity 0° account for and driving the to source that field due angular andthe compared sound pressure is set to the and to the expredictions of allsound sound of K system depend on the baffle, radiated three models. first to present, obBH( ) 1 ( 90°). source −1 type sound FV an =equivalent [1] was the effects. diffraction driving the sound Vanderkooy mine the[3] assumes that the driving pressure itself. Olson 1g DESCRIPTION ge2 cosed diffraction cabinet edge is to express on theCOMPARISON as follows: AND 2 .choosezero sound source for edge-relat in the shadow baffleregion OF THREE we and the sound pressure in this field depends l results concerninMODELING on a finite APPROACHES FOR CABINET In this paper perimenta the radiated sound region (7)(1)theFig. 3. Geometry baffle a piston mounted is due to radiation from edges only. We EDGE DIFFRACTION the geometric Vanderkoo used serving that baffle. thus have pressure for K [2] used model. the (r, ) V( ) 1 for 90°, and KV( )y 0 for >to calculate angular to the baffle d (B&H) P 90° for ometry of the Vanderkooy model. form factor Fig.diffraction Hawksfor 2 definesdue the and (r, ) K( ) baffle the wedge along angle for the boundary Bews and W P drive to model propagate between rays pro- zones. The wedge and illuminated diffraction sound shadow 1.2.1 Elementary Edge Diffraction angle the edges, theory of defined Sources by by considering their approach,is are scattered a sectionwhere by the piston view along the and edges. In tional secondary The B&Hproduced model assumes form ofomnidirec that the baffle. each elementary edge the baffle edge al The pressure of angle angular is the angle necessound is anout surface element is sending infinitesim sary to turn around the baffle ) is the the isotropic spherical wave in baffle, K( ) series of characteris an P baffle and (r, factor forcompletely, the wedge ducing a phase oppositionwhich on an infinite the Therefore the with thebetween main piston. angular form theory. The B&H when situated driving sound pressure, edge sources. [3] derived an polar angle the oy ld diffraction and is and is the factor for Vanderko the source. Sommerfe omnidirectional of model, axis using n. given sources n and the istic of a the edge edge sources is no longer angle of observatio of observatio pressure induced by phase direction diffracted y pressure on the projected concerning the The elementar as tal results highly signifihighly dependent wave are −jkrP oy’s experimen can be expressed e Vanderko the edge diffraction (2) dl. on of = 90° 2 r P behavior g the phenomen r = L, of great interest. concernin and Wright cant and = F P drive ncurrent literature contradictory, dP edge r, However, (3) is somewhat of the major inconsiste conto diffraction summary of edge analysis an excellent on finite-element dP edge results are provides P edge = o modeling Wright relies , and his findings cies [4]. ts. Wright’s around edge edge diffraction sider cabinet by practical experimenent of the DED model, proed corroborat to edge element dl = for the developm diffracwhere piston center baffle edge, are very important in the following. baffle edge distance from discussed l length along tion of the L outlined in as will be a representa jected differentia to all models n point Fig. 1 shows which is common observatio center to L d 1043 from piston tion geometry, 9, distance 2004 July r
(8)
Edge Dipole (DED) Model for Cabinet
Diffraction Effects AES Journal - Vol. 52, n°10 - 2004 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 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.
t received *Manuscrip August 13. July 30, and
23; revised 2003 October
Fig. 2. Description of wedge J. Audio angle Eng. Soc., Fig. 1. Geometry common Vol. 52, W and shadow to No. all 10, approaches for characterizing baffle edge and illuminated diffraction. 2004 October zones for two kinds J. Audio Eng. Soc., Vol. 52, No. of baffles 10, 2004 October
2004 October 1044 No. 10, Vol. 52, Eng. Soc., J. Audio
studied.
1045
Proceed
ings of the
Institute
Proceed ings of the s Institute Proceedings of the Institute of of Acoustic of Acoustic Acoustics
s
= ?? + EVAC we look at LIGIBILITY impact of the second image, + INTEL the sound. 3 O INTELLIGIBILTY ’S TAKE the red ignoring Areas tells : “PAâ€? “THE sound VS. in red ANCE AUDI P.A.â€? FACTURER & STI are defined us something different. pressure away from MANU PERFORM As discussed earlier, venues of the philosoph the primary levels 10db down as having unaligne This image past had yaudio systems designed SPEAKER public address. source. with one from that maximize mission a primary in mind – d sound coverage is showing delay The systems used This sis, France between A LOUD components source, s STI,the throwimage reveals Marcous based arrays to maximize announcer, and volume aof the and thereby Franceensuring at least STICS, would officially for it also is intelligibi sis, most patrons large problem more than 30mson criteria knew L-ACOU who madehave maximizi lity issues Marcous was not that last goal/run/touchdown. ng the echo/del always considered‌. STICS,Intelligibility in delay sound propagat United Kingdom with the due to a good A. Nagel r L-ACOU STICS, London, “less is Kingdom ion of each the distance from STI rating, however ay problems mind an g, United C. Montrezo L-ACOU . A person moreâ€? “old stadiumâ€? array would each Today we use STiPA (Signal Transmission the dia Consultin seated sound, render the source. The echo actual sound G. LeNost Index for Public Vanguar Address) complete to give the intelligibility of a sound system. would have absolute announc valueerto and delays This with an Originally D. Yates problem developed in the 1970’s as the STiPA long echo. industry an objective standard withis STI, concerni gives thedifficult to understa caused by the to addtoloudspea which predict and ng fewer the measure andability of a sound system nd, and reproduce speech in a particular optimize numbersources bring to to ker system acoustic environment. vs. echo/del SPLto grow in sound eelements ay issue below continue while reducing , thereby ION is highly intelligibl a similar the and the world show and echo caused creating a morenot new; the most Source , the safe around Technology INTRODUCT 3.1 Line & STiPA: common high quality distribute this sound, increase Is venue, venues STI by distance 1 timeus? the for both answer with five d system offooling sporting with this and between demand 12-eleme that event. Also ce to the qualitySize isn’t all that Thesmodern comes a“line-source nt line source loudspeakers. will further arrayâ€? of the was ment, worship, developed by Christian Heil in States, importan increase outside Entertain together. United 1992, revolutionizing live sound. What was array systems. The images as Wavefront of equal Sculpture With these balance during andtermed a the TechnologyÂŽ find their become g loudspeakers to provide high to the capacity. activities quality, full has Union and in allowed bandwidth, turers high volume tion for audio ncoverage patrons evenlyintegratin Europea fromemergen the frontcy reproduc evacuation of very and manufac to rear of a venue, even a the way large one. Over time, for thisthe in both s, talent technology d but lead has grown mid- and made throughout onward thetoindustry controlle , engineer many installed tor systems its way into sound just conform smaller n moves It is common the“line to see to not systems. eventhe array inmentâ€? leaving operators ; legislatio and annuncia bananasâ€? hanging down not simply atturers for concerts, but alarm also however in performance “sports-ta patron manufac te systemsvenuesr, ofasevery voice type, matters, and stadiums. large athletic arenas reevalua nt with Thewewide for the including pattern audio systemequipme must coverage Moreove ability sound ; to project the sound , if not requiring upper ce centers. andquality evenly from the lower to seems to be a perfect stadiums accurate nce soundlonger justdecks nt to a stadium. highest However this thematch performa , and conferen full range, the match in heaven‌ is not always made require n. It’s no audio equipme churches to provide turer of evacuatio arenas, y, operators& bin systems can a manufac in popularit sized theatres, of horn So what s to grow g the “echoâ€? high continue for the event. ce, eliminatin reproduction to balancingof line experien solutions use Figure the quality music 3:control working SPL impact, n through concert present network 5 arrays integratio STICS will do? n system r amplifiers, and in place and in L-ACOU evacuatio controlle gy changeslive equipment case studies, ents, and g, smart technolo tion, Using severalaudio, STI requirem ker monitorin discussion of presenta nce pad for gy, loudspea through performa s. technolo as a launchmanufacturers, attendee source array . This will serve the session nce audio and switching by performa le discussion within roundtab the works ration, and demonst BABYâ€? Figure 1: SPL impact,IN’, GET ROCK 3 arrays ed by sound, be. D: “LET’S attention not bombard that are at us to get our OF SOUN simply an lly few places THE ISSUE there are targeted specifica “PAâ€? is no longer rs and the 2 action world, us, or where the ce forFigure the spectato d, non-stop occurs around As you barrage, 4: Delay this can fast-pace experien to simply impact, our see, In immuneoverlapping 5 arrays of an auralthe top image ental that and SPL no longer deliverer it environm the would shows evenand echoing optimizat events are be more but rather on ion.stadium better Sporting intelligibl a few a fullsound In fact, horns red zones, ng to the man e and easier ement system, demandi reflecting even coverage than through announc rs are sitting es. and audience shrieking to listen after, substant between spectato before, ial delaybefore, to. However anthem . Based the players themselv ce, trying onprices, STI predictio nationalintelligibl in ticket the second loudspeakers, with more the system mismatch e audio d rise the experien es of a tinny through this system n, give image shows solution. fromticket, this solution priced g to the now the continuemusic pumping the days highwould us even Gone are grandstand. With Are line-sourteams are scramblin added to the quality score quite five audio sources more nal ces ce, with for value poorly, despite around the above a poor– choice simply notFigure event and professio inment experien Delay being the the work 2: arrays for3 large for the entire sports-ta when it impact, problem more Venue operators excited venues comes to – as each during play. in, and keep them and multiple proper STI then? Does the array and intelligibi width, overlap ons flowing.(example sources, propagates into to lure fansIn these images, we see a typical the and even the concessi lity? As 2).stadium audienceeither So whatsidecreating area beingvenue, or to get line source array systems. theby covered coverage shown, three 12-element audience the echo the solution? The dots shown the overlap inis yellow in being on the top image problem indicate impact zones, with open circles the sound is the pressurehit from many (example representing a “-3dbâ€? down point for the loudspeaker. As you1), see, there is a very even and consistent canor delay/ST directions coverage across the seating area. I problems would create even SPL The system as designed Vol. and33. anPt. optimized 6. 2011STI rating based on the definitions of STI. However, when Vol. 33. Pt. 6. 2011
Performance audio + intelligibility + evac = ?? a loudspeaker
manufacturer’s take Institute of Acoustics - Vol. 33. Pt. 6. - 2011 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. Vol. 33.
Pt. 6. 2011
29
Environmental Credentials
MANUFACTURING, STORAGE AND SUBCONTRACTING
GREEN SOUND SYSTEMS
RECYCLING
• wooden pallet recycling • L-ACOUSTICS line arrays have replaced Assembly plants, storage, and R&D the wall of sound from the ’80s • paper and cardboard recycling: systematically departments are all local. 100% of our sorted at every workstation and collected by • acoustic energy focused on the audience, suppliers and subcontractors are located in specialized companies less noise pollution France or Europe. • minimized acoustical interferences and • recycling of computer equipment and • SIMEA joinery: Alsace, France electrical energy waste consumables • electronic assembly: Germany MODERN ELECTRONICS • assembly of the loudspeakers: Marcoussis, LOUDSPEAKER COMPONENTS France • all metallic parts used in the loudspeakers • origin of speaker parts: European region are recyclable • high-powered Class D amplification of LA8 electronic • wood: from renewable forests in Finland • wood cabinets: no toxic product rejects and Lithuania • elevated energy efficiency close to 85% • wood: L-ACOUSTICS participates in a (versus 50% in the ’80s) reforestation program for the Baltic area • highly efficient power supplies sophisticated system control
30
and
PHOTO CREDITS Page 4
Paralympics Opening Ceremony London 2012 – Photo credit: Scott Willsallen
Page 8-9
Freeman Coliseum - Photo credit: Freeman Coliseum
Page 10 – 11
rewirpowerSTADION, Germany - Photo credit: VfL Bochum 1848
Page 16 Page 17
Rogers Arena, Canada - Photo credit: Jessica Haydahl / Vancouver Canucks Rogers Arena, Canada - Photo credit: Jessica Haydahl / Vancouver Canucks + Rogers Arena, Canada - Photo credit: John Riley
Page 18-19
Spaladium Arena, Croatia - Photo credit: Dicroic
Page 20
Tampa Bay Times Forum, USA - Photo credit: Dan Palmer
Page 21
Tampa Bay Times Forum, USA - Photo credit: Ryan Joseph
Page 22-23
BYU Marriott Center, USA - Photo credit: Jaren Wilkey / BYU
www.l-acoustics.com
L-ACOUSTICS 13 Rue Levacher Cintrat 91460 Marcoussis - FRANCE Tel :+33 (0)1 69 63 69 63 Fax : +33 (0)1 69 63 69 64 E-mail : info@l-acoustics.com
L-ACOUSTICS DE Steiermarker Str. 3-5 70469 Stuttgart GERMANY Tel:+49 (0) 711 89660 232 Fax:+49 (0) 711 89660 233
L-ACOUSTICS UK PO. Box Adler Shine - Aston House Cornwall Avenue - London N3 1LF UNITED KINGDOM Tel: +44 (1) 722 411 234 Fax: +44 (1) 722 411 236
L-ACOUSTICS US 2201 Celsius Avenue, Unit E Oxnard, CA 93030 USA Tel: +1 (805) 604 0577 Fax: +1 (805) 604 0858