Wednesday, July 31, 2013
Meyer Sound D-Mitri Drives An Immersive Undersea Experience At Denmark’s Blue Planet
Digital audio platform mixes, times and processes more than 400 custom-recorded tracks
The new Blue Planet in Kastrup, Denmark, is Europe’s second largest aquarium, and it has won accolades not only for its variety of marine life, but also for its striking whirlpool-inspired architecture and imaginative application of audio technology.
To support an immersive undersea experience, more than 400 tracks of custom-recorded audio are mixed, timed, and processed through a Meyer Sound D-Mitri digital audio platform. The audio is then distributed to 57 self-powered Meyer Sound loudspeakers installed throughout the exhibit areas.
“In most aquariums the underwater experience remains apart and behind glass,” says Arne Kvorning of exhibit designers Kvorning Design and Kommunikation. “At The Blue Planet, the underwater experience comes out and surrounds the audience, due in large part to the sound and lighting design.”
Anders Jørgensenof Kastrup-based AV consulting and integration firm Stouenborg served as both sound designer and project manager for the installation. Working in close collaboration with Kvorning Design and Kommunikation, Jørgensen seamlessly integrated a variety of unique soundscapes with corresponding lighting and visual effects in each exhibit area.
The D-Mitri system was at the heart of the concept, managing all audio functions and show control commands for Coolux Pandoras Box Server systems and a MA Lighting GrandMA2 light desk.
“With D-Mitri, I could work with an almost unlimited number of audio tracks, instead of being confined to stereo or 5.1 surround,” says Jørgensen. “I could load all of the tracks I created in the studio into D-Mitri and do the final mix in the aquarium, fine-tuning the intricate mixes in the rooms where they would be heard. This capability, when combined with Meyer Sound’s SpaceMap® multichannel panning software, gave me the perfect tool.”
The audio system includes the UPJ-1P VariO loudspeakers and USW-1P subwoofers. It also features various Meyer Sound low-voltage loudspeaker models that allow DC power and audio signal to be delivered over a single cable, reducing installation costs. They include the MM-4XP self-powered loudspeakers, UP-4XP 48 V loudspeakers, and MM-10 subwoofers.
“The sound design in the exhibit areas works in harmony with the subdued lighting inside the tank, and in the cathedral-like space in front of the window,” says Jesper Horsted, COO of The Blue Planet. “Stouenborg has created an intimate underwater experience—this in spite of a large room often filled with visitors.”
Located five miles outside Copenhagen, The Blue Planet (Den Blå Planet) houses 53 aquarium tanks that contain more than 20,000 fish and other aquatic life. The Danish architectural firm 3XN designed the building, with acoustical design provided by Gade & Mortensen Akustik A/S.
Adamson Energia E15 Line Arrays Integral To Daft Punk Album Launch
Norwest Productions utilized an Adamson Energia E15 "surround" system to mimic a night club dance floor at the Daft Punk premiere in Australia.
Daft Punk recently premiered their newest album, Random Access Memories, at the Wee Waa Showground in Wee Waa, Australia.
The Wee Waa Showground is situated in the rural town of Wee Waa, population 2,100, approximately 350 miles northwest of Sydney. The annual 3-day festival headlined the premiere.
Norwest Productions, headquartered in Sydney, was tasked with designing and implementing a sound reinforcement system that would surround a circular LED dance floor located in the middle of the showground show ring. The dance floor – constructed for the event – was approximately 85 feet in diameter and subsequently dubbed the largest outdoor dance floor in Australia.
“The idea was that the audio on the dance floor would sound like a nightclub with four hangs of PA outside each quadrant of the dance floor,” explains Scott Harrison, Norwest Productions FOH engineer and system designer. “We knew the Adamson Energia E15 system was perfect for the job.”
Each of the four arrays consisted of eight Energia E15s with six T21 subwoofers. The line arrays were flown from inside of towers constructed of scaffolding located in the four corners of the dance floor. The T21s were ground stacked (2x3) in front of each tower.
“Since the towers were only 7 feet deep, the rigging system on the E15 made flying the PA a breeze – another big plus for the system,” Harrison adds.
The E15 is a 3-way system loaded with two 15-inch and 7-inch Kevlar cone drivers, and two 4-inch Adamson NH4 compression drivers. The T-21 subwoofer boasts an Adamson Symmetrical Drive multilayer 21-inch Kevlar driver providing a maximum SPL (continuous) of 140.5 dB.
“I was confident in using the E15s because the boxes have tremendous clarity and fantastic sound quality,” Harrison continues. “We wanted to ensure the most faithful representation of Daft Punk’s creation as possible.
“The system gave tons of headroom. I had no problem turning the volume up, knowing that the E15 still had room to move. The subs provided the low frequency energy to make listening to the album a body-shaking experience.”
The arrays were powered by a total of 40 Lab.gruppen fP 6400 and eight FP 10000Q amplifiers. Processing consisted for 9 Lake DLP and 2 LM26 digital audio processors.
Norwest Productions deployed a DiGiCo SD 8 at FOH to bring in both the main and backup replay machines on MADI, the backup CD in AES3 and also have analog backups for each of those devices.
On the night of the show, right after the last firework went off approximately 3,200 people converged on the dance floor. The LED dance floor lit up, lights were directed at a large rotating disco ball hanging above the crowd and the music began.
“Daft Punk’s final track from the album, “Contact”, contains a sweep from around 80hz all the way through to 15k or so,” Harrison concludes. “To hear that sound, hear it smoothly make its way through that entire range, without becoming harsh or sharp or overwhelming, really is a beautiful thing. The Adamson system was amazing.”
Adamson Systems Engineering
RG Jones Deploys Martin Audio W8LC For Coronation Festival Gala
W8LC and W8LM arrays for classical reinforcement
RG Jones’ busy summer season with Martin Audio line arrays and other components continued in July with the Coronation Festival at Buckingham Palace. This followed the Glastonbury Festival and the simultaneous Henley Festival, which both placed further demands on Jones’ Martin Audio inventory.
The audio specialists had been sub-contracted by main technical production company Hawthorns, which was in turn introduced to the project by event organizer, Media 10. The Royal Warrant Holders Association hosted both the Coronation Festival and exhibition in the Gardens of Buckingham Palace.
RG Jones, themselves Royal Warrant Holders, participated in the exhibition (along with more than 200 others) while simultaneously providing sound reinforcement for the Gala concerts. In fact the RG Jones stand exhibited an original Morris J-type—the same as the one used by the original founder Ronald Geoffrey Jones back in the 1920s.
As with Glastonbury, RG Jones’ project manager Ben Milton relished the challenge of project managing a large-scale event, but unlike Glastonbury where Martin Audio’s W8L Longbow system was deployed, Milton said the system of choice this time would be the company’s W8LC and W8LM systems.
“We have used the W8LC system for so many classical concerts of this size in the past that we were confident it would sound fantastic and give us no sleepless nights,” Milton states. “It just works so well.”
But the implementation of the system for the Raymond Gubbay promoted Gala concerts was far from straightforward, as Milton emphasizes. “Aside from the stringent guidelines and provisos we had to follow, the PA wings were extremely wide—around 310 feet between left and right––which required an additional L/C/R center system flown over the stage.”
And with a wide range of artists celebrating 60 years of the performing arts—including Dame Kiri Te Kanawa, Katie Melua, Russell Watson, Katherine Jenkins, Laura Wright, Only Boys Allowed, The Feeling, as well as the National Youth Orchestra and Matthew Bourne’s New Adventures–—there was quite a line-up of talent for Milton and Simon Honywill at the FOH mixing desk.
“I love the challenge of having 250-plus inputs on the desk with multiple acts,” says the former, explaining that this included active splits from the stage, sent to the BBC broadcast OB trucks.
Out on each wing, in front of the Palace terrace, two hangs of 14 Martin Audio W8LC elements were mounted on smart PA masts.
A further three center in-hangs formed the thrust canopy PA. This comprised six W8LM Mini line arrays (with two W8LMD Downfills at the base), flanked by two hangs of eight W8LC to produce an L/C/R image.
Under the thrust stage, there were four gauze-covered WLX subs with a further six ground stacked WLX under the two speaker masts (three per side). Finally, eight Martin Audio DD6 Differential Dispersion horns were positioned along the front lip as close fills.
All processing was carried out in an XTA Audiocore environment, with system technician Mark Edwards equalizing and time aligning the system remotely via a wireless tablet.
Milton says, “The in-hangs had to do all the work and we had to deal with timing issues between the wide hangs and the inner hangs. The LC’s worked fantastically well and provided full 330-foot coverage without delays for 20,000 people. In fact when you sat in the middle of the auditorium it was just like a cinematic setting carefully time aligned to get the stereo image, and wherever you went it delivered and it was still high fidelity sound.”
The audio complemented the width of the stage, he notes, adding that both Tim Davies [BBC Television sound supervisor] and the orchestra had expressed their delight with the sound. “The whole event was special because you simply forgot where you were. The Palace provided an amazing backdrop.”
Supporting system designer Milton, were FOH engineer Honywill, system tech Edwards, and James Breward (system/comms), and on stage, Mark Isbister (patchmaster), Alison Dale (RF and orchestral miking), Damon Dyer (monitors) and Ian Threlfall (stage).
Aligning A Subwoofer With Full-Range Loudspeakers
The process should typically entail three primary items
I’ve heard the question “How do I align a subwoofer with a full-range loudspeaker system?” asked many times, and thought it might be interesting to delve into this to see if I could come up with an answer.
The task of adding a subwoofer to a loudspeaker system to increase the low frequency bandwidth should typically entail three primary items.
• The relative bandwidth of the subwoofer and the full-range system (crossover)
• The relative output level of the subwoofer and the full-range system (gain)
• The relative arrival time of the signal from the subwoofer and the full-range system (delay)
It is this last item that is perhaps the most challenging. This is the one that we will primarily investigate. We will also look at the first item briefly.
With these taken care of, item two should not be too much of a problem.
Loudspeakers, by their nature, are band pass devices. To simplify the measurements and make it easier to see what’s going on with the graphs I will use high-pass and low-pass filters instead of actual loudspeakers. The results will be the same with one exception—microphone location.
Since our examples don’t use a microphone (only electrical measurements) it can’t be moved to a different location. This can be much more critical for measurements at higher frequencies as the directivity response of a loudspeaker will lead to differences in the measured response of a device at different locations. For devices that are for the most part omnidirectional in the lower frequency region this will not be an issue.
There is another issue, of which one should be aware, concerning microphone placement that could lead to measured differences. That is the potential change in path length from the two devices under test (lower frequency device and higher frequency device) to the measurement microphone (or the listeners’ ear). At one mic position there may be very good summation.
At another location, where the path length difference has changed by one-half wavelength of frequencies in the crossover region, there will be a notch (cancellation) in the summed response. When making field measurements it is advisable to place the microphone(s) in position(s) that are typical of magnitude and arrival time differences to which most of the intended coverage area will be subjected.
Let’s imagine a hypothetical system that has a full-range cluster that reproduces 60 Hz – 14 kHz adequately. We will add a subwoofer that is physically displaced from the full range cluster. The subwoofer reproduces adequately down to 30 Hz. These response curves are shown in Figure 1.
Figure 1 – Magnitude response of individual simulated loudspeakers. (click to enlarge)
We want a crossover at 100 Hz with a 4th order Linkwitz-Riley alignment. We can simply apply a 4th Linkwitz-Riley low-pass filter at 100 Hz to the subwoofer since its response in relatively flat well above the intended crossover region.
This is not the case for the cluster, however. Its output is already beginning to decrease with decreasing frequency through the intended crossover region. We will need to apply an electrical filter that, when combined with the natural response of the cluster, will yield an acoustical output that matches a 4th order Linkwitz-Riley filter with an fc of 100 Hz.
Figure 2 shows the natural output of the cluster and the target Linkwitz-Riley response along with the cluster’s output after it has been high pass filtered. A 3rd order Butterworth high pass at 115 Hz was used to get this response.
Figure 2 – Magnitude response of cluster w/o HP filter (blue), target Linkwitz-Riley response (green) and cluster with HP filter (red). (click to enlarge)
A lower fc and a parametric EQ filter might be used to achieve a more exact match. The response shown will be close enough for our purposes.
When the outputs of the two devices are combined we get the responses shown in Figure 3. The summed magnitude response is not at all what we want. It is clear that something is causing cancellation.
Figure 3 – Magnitude response of individual pass bands and the summed response. (click to enlarge)
We know that the acoustic Linkwitz-Riley response of each device should sum to a flat response. Since it doesn’t, this would seem to indicate the problem is a misalignment of the two devices in the time domain.
Looking at the Envelope Time Curve (ETC) of the pass bands (Figure 4) confirms that they are not synchronized. We need to delay the cluster, but by how much?
Figure 4 – ETC of individual pass bands. (click to enlarge)
If we choose to align the cluster’s peak arrival with the peak arrival from the subwoofer we need to delay the cluster 14.7 ms.
Alternatively we might choose to try to place the arrival of the cluster more towards the leading edge of the subwoofer’s ETC. This will require approximate 10 ms of delay for the cluster.
The frequency and time domain of both these scenarios are shown in Figure 5 and Figure 6.
Figure 5 – Magnitude response summed response with the cluster delayed 10 ms (red) and 14.7 ms (blue). (click to enlarge)
Figure 6 – ETC of the summed response with the cluster delayed 10 ms (red) and 14.7 ms (blue). (click to enlarge)
Neither of the frequency domain curves looks like what one would consider good summation (reasonably flat response). The time domain would seem to indicate that the shorter delay is closer to the ideal response than the longer delay.
We could go on guessing at different delay times in an attempt to optimize the response in both domains. Hopefully there is a better way.
The underlying problem is that we have only low frequency information output from the subwoofer.
From the equation:
Δt =1/ Δf
where Δt is time resolution and Δf is frequency resolution, we can see that high frequency resolution (small value of Δf) will yield low time resolution (large values of Δt).
We need higher frequency output from the subwoofer (corresponding to higher Δf, lower frequency resolution) to increase the time resolution in order for us to know when to position the cluster.
If possible, we can bypass the low-pass filter on the subwoofer to get more high frequency content in the output signal.
This may help in more precisely determining the arrival time of energy from the subwoofer.
Let’s assume that we can’t do this or if we can that it still doesn’t give us sufficient time resolution.
What we need is a way to get precise time information without high frequency content. This is a seemingly impossible task, but only so in the time domain. In the frequency domain there is a metric available that yields quite precise relative timing information.
This is the group delay. The group delay is defined mathematically as the negative rate of change of the phase response with respect to frequency.
τg = −dφ / dω
Figure 3 and Figure 4 show different views (domains) of the same measurement for the individual pass bands. If we look at the group delay of this same data in Figure 7, we can derive some valuable information.
Figure 7 – Group delay of the cluster (red) and subwoofer (blue) with crossover filters in place. (click to enlarge)
The high frequency limit (plateau) of each curve indicates the arrival time of the signal from that device.
From this we see that the cluster arrival time is approximately 3.3 ms. This correlates very well with the ETC in Figure 4.
Don’t let the appearance of the subwoofer curve in the high frequency region be bothersome. This is due to the low signal-to-noise ratio of the measurement above 400 Hz. Referring to Figure 3 the output of the subwoofer is less than -24 dB at 200 Hz.
Our use of a fourth order filter would indicate a level of less than -48 dB at 400 Hz and decreasing rapidly. It’s no wonder there is a SNR problem at higher frequencies.
We can look at the subwoofer curve around 300 Hz to get an indication of the high frequency limit of its group delay. This turns out to be approximately 11.0 ms. The group delay of the cluster at this frequency is approximately 3.9 ms.
This is a bit different than the 3.3 ms at higher frequencies, and is caused by the phase shift of the high-pass filter and the natural high-pass response of the device. The low-pass filter being used on the subwoofer will have similar phase shift, and consequently, similar group delay differences in the high frequency region if our measurement SNR was good enough to see it.
Taking the difference in 11.0 ms and 3.9 ms we now have a value of 7.1 ms to use as our delay setting for the cluster. This yields the summation, along with the individual pass bands, shown in Figure 8 and Figure 9. This is almost the exact response we desire.
Figure 8 – Magnitude response of individual pass bands and the summed response with the cluster delayed 7.1 ms. (click to enlarge)
Figure 9 – ETC of individual pass bands and the summed response with the cluster delayed 7.1 ms. (click to enlarge)
There is less than 0.5 dB error in the vicinity of 150 Hz. This error is due to the output of the cluster and high pass filter not exactly matching the Linkwitz-Riley target (see Figure 2).
There is one more item that I think might be of interest in helping to see how a low-pass filter response affects apparent arrival time. I say apparent because it only appears that the arrival time is changing. Figure 10 and Figure 11 show the ETC and IR, respectively, of a 4th order Butterworth low-pass filter.
Figure 10 – ETC of low pass filter with different corner frequencies. (click to enlarge)
Figure 11 – IR of low pass filter with different corner frequencies. (click to enlarge)
The only difference in these curves is the corner frequency (-3 dB point) of the filter. The true arrival time for all of these filter curves is 5 ms. A complementary high pass filter with an arrival time of 5 ms will combine properly with its low pass counterpart in the graph.
If the high pass is delayed so as to place the arrival so that it occurs later than 5 ms there will be errors in the summation of the filters just as was illustrated in Figure 5 and Figure 6.
We have seen how the response of an electrical filter can combine with the response of a loudspeaker to yield the desired response (alignment) from the combined output. We have seen how the low pass behavior of a device may make it appear that its arrival time is later than it actually is.
We also demonstrated how to use group delay to determine the correct delay setting with relatively high precision when the high frequency output of a device is limited due to its low pass behavior.
I hope that some will find use for these techniques.
Charlie Hughes has been int he pro audio industry for over 20 years, having worked at Peavey and Altec Lansing. He currently heads up Excelsior Audio Design & Services, a consultation, design and measurement services company located near Charlotte, NC. He is also a member of the AES, ASA, CEA and NSCA, in addition to being an active member of several AES and CEA standards committees. width=b
Woodlawn Baptist Church Upgrades With WorxAudio
WorxAudio TrueLine all-in-one line array provides pristine sound quality and broad horizontal dispersion.
Woodlawn Baptist Church,located in Baton Rouge, LA, recently installed a new sound reinforcement system featuring a WorxAudio Technologies TrueLine line array.
Technical Services Group (TSG), a design/build firm also located in Baton Rouge, was contracted to design and install Woodlawn Baptist Church’s new sound system.
After meeting with church management to ascertain their expectations, the TSG team ultimately deployed a WorxAudio TrueLine X5i-BA biamped all-in-one line array that was augmented in the low frequency range by the inclusion of a WorxAudio X115i extended bass subwoofer.
“Woodlawn Baptist Church’s services are a blend of traditional and contemporary elements,” explains Scott Richard, TSG’s system designer. “Much of the music is provided by a praise band and vocal team, so the ability of the new sound system to accurately reproduce music was considered extremely important.
“The sanctuary itself measures 60 feet square with a balcony on the opposite wall from the stage / pulpit area. There is fixed seating, carpeted flooring, and a steeple-type ceiling that measures 40 feet at its peak. The vocal team resides behind the Pastor on stage.”
“It reached a point where the old system was so unusable, they began using a portable PA,” adds Patrick Meek, TSG’s VP of sales and marketing “The room suffered from inconsistent coverage and it would routinely feedback before reaching a suitable volume that would enable the congregation to hear.
“In addition to the new system’s music reproduction characteristics, a high level of speech intelligibility was equally important, as was a clear line of sight to the stage area. This is precisely why we decided to deploy a single, central loudspeaker system—and the WorxAudio X5i-BA was the perfect choice.”
The WorxAudio X5i-BA is a two-way, high efficiency line array loudspeaker that integrates five modules into a single, compact enclosure incorporating five high frequency drivers and ten 8-inch cone transducers.
The biamped version of the enclosure is powered by WorxAudio’s PXD2580 amplifier with its dual channel, 2500 watt by 800 watt power amp and its integrated DSP-X5 signal processor.
The TSG installation team flew this loudspeaker system over the front center area of the stage with the WorxAudio X115i subwoofer residing at the top of the cluster.
When asked about the choice of passive systems (external amplification) as opposed to active models with integrated power, Richard notes this was a matter of preference on the church’s part—primarily out of concern for easy serviceability should it ever be required.
“The dispersion of this loudspeaker system is 160 degrees horizontal by 40 degrees vertical, and this provided just the right amount of coverage throughout the room without being overbearing—either audibly or visually,” Richards explains. “The system presents a clean, uncluttered appearance while delivering both the speech intelligibility and music characteristics that our client deemed so essential.
“With the inclusion of the X115i subwoofer driven by WorxAudio’s PXD8080 amplifier, the end result is a clean, clear, natural sounding loudspeaker system with a rich, full bottom end.”
Both Meek and Richard were very complimentary of WorxAudio’s customer and technical support services throughout the duration of the project.
“Chris (Rachal) and Ezra (Kelly) were great to deal with,” Richard reports. “When we had questions, they were very responsive and they also assisted us by modelling the loudspeaker setup using EASE Focus. They had our backs every step of the way.”
“Our customer is very happy,” Meek concludes. “They are excited about having a system that meets the requirements of the room. Speech intelligibility is excellent, music sounds big and full, and the entire setup is very streamlined so as not to be visually distracting.
“With the assistance of WorxAudio Technologies, our company has yet another successful project under its belt.”
Circuit Of The Americas Hosts Formula One With Community
Community R-Series loudspeakers are installed at Austin's Circuit of the Americas (COTA)
Austin’s Circuit of the Americas (COTA) is America’s first purpose-built Formula One racing track.
Completed in late 2012, COTA’s campus includes the Main Grandstand with VIP Lounge, the Grand Plaza with food court and shops, a 251 foot (77m) Observation Tower and the Pit Building with an adjacent Media Center.
The track includes bleachers at several locations to supplement the Grandstand seating.
Although the Formula One and other races are the site’s main attractions, A/V systems play major supporting roles.
Architect Tilke’s Formula One designs include race control systems and basic audio and video systems but Circuit of the Americas chose to upgrade and/or supplement the A/V systems in many areas.
Circuit of the Americas retained consultant Acoustic Dimensions for many of the venue’s networks and for the audio and video system upgrades.
Acoustic Dimensions engineered the low-voltage systems and, in cooperation with Hughes Associates, led the effort to comply with the mass notification code.
AT&T, the overall campus technology contractor, chose Ford AV to assist in the A/V systems field design and installation.
The original audio specification consisted primarily of paging horns for race audio and public announcements. To meet COTA’s request for A/V upgrades, Acoustic Dimensions and Ford AV set up a loudspeaker performance evaluation for Circuit of the Americas’ management personnel.
Conventional paging horns were used as a baseline and two upgraded systems were offered for comparison. Circuit of the Americas selected Community’s R-Series, for their overall performance and sound quality, their reputation for long-term outdoor durability and their high sensitivity (efficiency) which reduced amplifier requirements and helped Circuit of the Americas meet its budget guidelines.
Community R2s, R.5HPs and WET Series loudspeakers are used in the Main Grandstand, on the track and in other outdoor areas. Community Distributed Design Series ceiling and surface-mount loudspeakers are used in the Main Grandstand, the Grandstand VIP Lounge and the Pit Building.
Community VERIS2 loudspeakers are used in the Media Center with the video systems. Audio electronics include Crown amplifiers, BSS London DSPs and Soundcraft digital mixing consoles.
Acoustic Dimension’s Craig Janssen says “Circuit of the Americas is very pleased with the choice of Community loudspeakers for these systems”.
Community Professional Loudspeakers
Tuesday, July 30, 2013
Church On the Move With Harman Professional Sound And Martin Professional Lighting
Mega-church utilizes Harman's Martin Professional Lighting and Professional Sound.
The term “mega church” might have been coined to describe Tulsa, Oklahoma’s 12,000-member Church on the Move.
At services, the church’s message is delivered on a scale that rivals major rock concerts, with full-scale lighting, sound and video in a sanctuary that’s bigger than many top music venues.
The rock concert analogy is appropriate in more ways than one – the church’s audio and video staff rent rather than purchase most of their lighting, giving them access to the latest Harman Martin Professional lighting gear to complement the church’s Harman Professional sound system.
“We rent 90 percent of our lighting and it gives us the freedom to change frequently and try new ideas and technologies. We don’t want to be left behind when the industry makes a major shift, ” said Andrew Stone, Church on the Move’s production manager and audio director.
Renting also cuts down on the need to retain additional maintenance staff – the church can handle all its lighting needs with two technicians.
“The rental model also lets us use high-quality gear without spending a ton of money. We can rent more equipment as needed for bigger events.”
Church On the Move utilizes a host of Martin intelligent lighting products including MAC III Profile lighting, MAC Viper Profile high-output 26,000-lumens fixtures, MAC 700 Wash 26,000-lumens lighting and TW1 tungsten wash lights.
Stone and crew will buy equipment when it makes economic sense, and recently purchased a number of Martin VC-Dot 1 fixtures, individually controllable LED dots that are used to create customized video displays.
The VC-Dot 1 provides new ways to integrate video technology into stage designs, ceilings and other structures.
“We can use the VC-Dot 1 as a design element, as a backdrop or split it up for use in several auditoriums,” Church On the Move lighting designer Daniel Connell states. “It’s amazingly versatile and enables us to easily add dramatic visual impact to a space.”
Connell notes that music is a key element of Church On the Move’s services and that along with the Harman JBL, Crown and BSS-based audio system, a major role of the Martin lighting is to create a modern concert looking feel.
He doesn’t want “a lot of flash” but the ability for the lighting to set a mood or tone on stage and throughout the sanctuary.
“We don’t have a backdrop or a physical stage set so the lighting is our set,” Connell said. “Other house of worship lighting designers don’t do it this way but we feel it’s an interesting and powerful way to do it.”
Connell finds Martin fixtures provide superior color range and saturation; while some fixtures fall off toward the saturated end of their range and some moving lights aren’t the best at delivering a certain color, Martin handles the full light spectrum equally well.
Stone agrees, noting that the church has tried every brand of high-end moving light in the six years Connell’s been on staff and that he and Connell prefer Martin’s richer colors and better look and “feel.”
Reliability is paramount, especially with rented gear.
“I don’t want rental fixtures dying in the middle of a service,” Connell states. “After a year of use you can start to have problems but I’ve never experienced that with Martin.”
Like many organizations, Church On the Move is bringing in more LED lighting for its reduced maintenance and energy costs.
Since 2010 Church On the Move has enjoyed the sonic benefits of a large-scale JBL, Crown and BSS Audio sound system, comprising 38 JBL VerTec line array element hung in four clusters and complemented by 16 JBL ASB6128V subwoofers, 10 flown and six under the stage.
Seven JBL AC28/95 speakers behind the perimeter of the stage provide front fill and the speakers are powered by 49 Crown MA5000i and 10 CTs 3000 and CTs 2000 amplifiers.
The speakers and amps in the sanctuary and other JBL speakers and Crown amps throughout the church are linked by BSS Soundweb London BLU-160 digital audio processors, and all A/V is networked using Harman HiQnet System Architect software.
“We recently had a conference with 2,500 worship and creative directors from around the country, and have held many major events and big services,” Stone said. “Many people came just to hear the JBL VerTecs because of everything they’d heard about them, and that says a lot. Like the Martin lighting, the audio system has performed admirably.”
Meyer Sound CAL Brings Clarity To Steel-and-Glass Atrium At National WWII Museum
The US Freedom Pavilion: The Boeing Center now relies on the Meyer Sound CAL column array loudspeaker to tackle the acoustic challenges in its massive vaulted pavilion.
At the National WWII Museum in downtown New Orleans, the US Freedom Pavilion: The Boeing Center now relies on the Meyer Sound CAL column array loudspeaker to tackle the acoustic challenges in its massive vaulted pavilion.
Using CAL’s beam-steering technology, New Orleans-based JBA Consulting Engineers has created a system that delivers highly intelligible music and speech while tailoring coverage for the audience size at an event.
The US Freedom Pavilion: The Boeing Center is a 36,000-square-foot angular edifice dominated by a five-story, steel-and-glass atrium which houses six wartime aircraft suspended in frozen flight, including a B-17 Flying Fortress.
Despite the acoustical hazards posed by surfaces of glass and concrete, the CAL loudspeakers allow the museum to direct exceptional audio clarity to the audience for almost daily programs of lectures, video screenings, and musical entertainment.
“We were originally skeptical about having decent sound in the space, largely based on prior experience in another pavilion using older technology,” admits Paul Parrie, associate vice president of operations for the museum. “But we are amazed at how well the Meyer Sound CAL system works here, and we are very pleased with it.”
Precise, uniform coverage of the 700-person capacity audience area is provided by two CAL 64 loudspeakers, aided by two UPJunior VariO loudspeakers for near-stage fill. Low end for music and video playback programming is supplied by dual 600-HP subwoofers. The CAL loudspeakers are programmed with two presets: one uses dual split beams on both sides for larger audiences, while the other uses a single beam at a steeper angle for smaller audiences.
“The wall opposite the stage is five stories of solid glass, and because the room is asymmetrical, the throw is much shorter on one side than the other,” notes Rob Pourciau, senior project consultant for JBA. “We needed loudspeakers that could tailor precise coverage for the space, then change coverage depending on audience size, while providing both high speech intelligibility and superb music quality.
“CAL is the only system that could do it all and still keep the architects happy with its unobtrusive appearance.”
In addition, two Meyer Sound UM-100P stage monitors provide foldback, and a Galileo loudspeaker management system featuring one Galileo 408 processor is used for optimization and drive. The pavilion’s event audio system also includes a Yamaha LS9-32 digital mixing console, Clear-Com intercom, and eight Shure ULX wireless systems which include Beta 58 handhelds and beltpacks with Countryman lavalieres.
All sound and lighting systems were designed by JBA Consulting Engineers, while New Orleans-based Soundworks handled system integration.
The US Freedom Pavilion: The Boeing Center was part of a recent $35 million renovation to the museum. Voorsanger Mathes, LLC was the architect and Woodward Design + Build was the general contractor. Since its dedication, the pavilion stage has hosted a broad range of high-profile speakers, including Pulitzer Prize-winning author Rick Atkinson and former vice president Dick Cheney.
Musical entertainment is often provided by the female vocal group the Victory Belles.
Dedicated in 2000, the National WWII Museum features interactive exhibits, artifacts of all sizes, and special programs that together reveal how the war was fought, how it was won, and what it means in today’s world.
Monday, July 29, 2013
Clearwing And L-Acoustics Kick Out The Jams At Summerfest
World’s largest music festival heard via K1, KARA, KUDO and ARCS WIFO
Recognized by Guinness World Records as the world’s largest music festival for the 15 consecutive years, Milwaukee’s Summerfest knows how to throw a party.
Serving up a smorgasbord of brats, brews and bands – over 700 national and regional acts performing on 11 stages – this year’s “Big Gig” at Henry W. Maier Festival Park on the city’s Lake Michigan shoreline drew more than 840,000 visitors over its 11-day run in late June and early July.
Milwaukee World Festival, the non-profit organization that runs the event, once again turned to local provider Clearwing Productions to handle audio production duties for the event.
Clearwing specified the use of more than 340 L-Acoustics loudspeaker enclosures for FOH throughout the grounds.
According to Bryan Baumgardner, Clearwing audio operations/logistics manager, eight of Summerfest’s nine largest stages – including the 25,000-capacity Marcus Amphitheater – featured L-Acoustics systems.
Five of those stages – the Marcus, as well as Briggs & Stratton Big Backyard, Harley-Davidson Roadhouse, BMO Harris Pavilion (formerly Classic Rock Stage) and U.S. Cellular Connection – utilized K1 for the primary house arrays.
Additionally, the system for the Johnson Controls World Sound Stage (formerly Potawatomi Stage) was built around KARA, while Uline Warehouse featured V-DOSC.
A new addition to Summerfest’s gear list this year was the use of L-Acoustics’ ARCS WIFO enclosures. At Jo Jo’s Martini Lounge, Clearwing vertically flew one ARCS FOCUS over two ARCS WIDE per side, which replaced two six-enclosure KIVA arrays used in years prior.
ARCS WIDE systems were also used on half of the stages for both front-fill and side-fill.
“We previously used standard ARCS boxes, but ARCS WIDE has a larger dispersion pattern that makes it particularly ideal for side-fill,” says Baumgardner, “Plus the power rating is better suited for front-fill applications. They worked perfectly and everyone was really happy with them.”
He adds that Clearwing has been providing audio for the festival since 1995 and first began deploying V-DOSC there back in 2000, shortly after acquiring its first rig.
Since then, L-Acoustics has been on the equipment spec every year.
“One of the primary reasons we use L-Acoustics is because of its high rider acceptability; nobody says ‘no’ to K1, KARA, KUDO or V-DOSC,” says Baumgardner. “We’ve been using these systems at Summerfest for a long time now and they consistently prove themselves to be the right choice year after year.
“It’s what the festival wants as well as what the artists want. We don’t have to convince anyone to use it.”
Less than two weeks after the close of Summerfest, Clearwing supplied 80 K1, 32 K1-SB and numerous other L-Acoustics enclosures for a huge Pearl Jam concert at Chicago’s Wrigley Field.
A portion of Clearwing’s L-Acoustics inventory is also regularly being used at Maier Park this summer for a number of ethnic festivals, including Polish Fest, Festa Italiana, German Fest, African World Festival, Irish Fest, Mexican Fiesta, Indian Summer, Asian Moon Festival, Arab World Fest and PrideFest.
Over Labor Day weekend, the Summerfest grounds will once again be packed as Clearwing provides concert systems for Harley-Davidson’s 110th anniversary featuring performances from Toby Keith, Aerosmith, Kid Rock, ZZ Top, Dropkick Murphys, Lupe Fiasco, Common, Brantley Gilbert, Doobie Brothers, Buckcherry, Joan Jett & the Blackhearts, Gaslight Anthem and Sublime, among others.
RCF USA Adds Ken Voss As Manager Installed Sound Products
RCF USA is proud to announce the addition of Ken Voss to their staff as Manager of Installed Sound products.
RCF USA is proud to announce the addition of Ken Voss to their staff as Manager of Installed Sound products.
Voss has served as an independent manufacturer representative in the Midwest for over 20 years with Starin, Online Marketing and JAMM Distributing. He has represented RCF in the region for over 10 years.
During his tenure as a rep, he’s been honored with numerous factory awards from the likes of Renkus-Heinz, Allen & Heath, Listen Technologies, Audio-Technica, etc. He has shared in the Audio-Technica Rep of the Year award while with Online Marketing, and has been named Rep of the Year with CAD/Astatic and Sabine.
Prior to that, he was Director of Operations for a sound contractor in the Chicago area.
His role as Manager of Installed Sound will be to help grow RCF business in the contracting and installation areas, develop go-to-market strategies, increase product knowledge and awareness, and improve company communications.
Friday, July 26, 2013
Gand Concert Sound Pitches In At Music Festival
Pitchfork Music Festival, held July 19-21 in Chicago’s Union Park, utilized a Nexo sound reinforcement system and Yamaha consoles.
Pitchfork Music Festival, held July 19-21 in Chicago’s Union Park, brought the best of emerging music to over 50,000 attendees.
This year, 40 artists entertained on three stages including Bjork, Solange, Lil B, R Kelly, Savages, The Breeders, Swans, and Wire.
Gand Concert Sound of Elk Grove Village, IL, provided audio production for both the Red and Green stages.
Red stage included 15 Nexo GEO T line array boxes per side, 16 Nexo CD18s, a Yamaha CL5 digital audio console at FOH, and a Yamaha M7CL for monitors.
The Green Stage audio set up consisted of 18 GEO Ts per side, 20 CD18s, and Yamaha PM5D-RH digital consoles for front of house and monitor mixing.
Nexo PS15R2s were supplied for the both the Red Stage (passive) and Green Stage (bi-amped) along with Nexo NX4x4 amps for mains and Yamaha T5n amps for subs, front fills and monitors, along with Nexo NX241 and 242 processors. Alpha E/f and S2 side fills were used on the Green stage
“Of all the fests in the USA, Pitchfork stands out as the place to be for fans of up and coming bands and indie’s who have established themselves as must-see acts,” says Gand President, Gary Gand. “It’s a great test of what our audio production set up centered around the Nexo systems can do. From a solo harp player to a 20 piece hardcore rap act and all points in-between.”
“Many, many kudos to Gand from the audio folks that the artists brought, and from us,” states Mary Jones, director of Pitchfork Festival Artist Production & Artist Relations.
Gand Concert Sound
Hanoi International Fellowship Installs First Danley System In Vietnam’s Capital
The Hanoi International Fellowship (HIF) non-denominational church recently installed Danley Sound Labs loudspeakers for sound reinforcement.
The Hanoi International Fellowship (HIF) is a non-denominational church serving both expatriates and nationals in Hanoi, Vietnam. It draws together a congregation of over four hundred people, representing over forty nationalities.
HIF recently moved to its first permanent building, and its challenging acoustics demanded pattern control from its new sound reinforcement system. Singapore-based Soundsmith Solutions Pte. Ltd. designed the new system using Danley Sound Labs SM-80 and SH-micro loudspeakers and TH-mini subwoofers.
The new sanctuary seats just over two hundred people. HIF’s services are punctuated by a full band playing contemporary music.
“Previously, the congregation met at a local 5-star hotel, and the hotel provided them with the usual hotel sound system,” said Pastor Jinggoy of Hanoi International Fellowship. “That system was uneven. It was too loud toward the front and inconsistent throughout the rest of the room. “The subs were boomy and the high-end was harsh.”
In addition to designing the system, Soundsmith Solutions also supplied the components. Pastor Jinggoy helped coordinate the church’s own contractors to install the system based on Soundsmith Solution’s drawings and specifications.
“The big challenge in the new space was its very low ceilings. Moreover, it used to be a warehouse, so none of the walls were designed with acoustics in mind,” Edwin Ng, project manager at Soundsmith Solutions Pte. Ltd., commented. “The challenge was compounded by the fact that there were few places to position loudspeakers that wouldn’t interfere with sight lines.
“The Danley Sound Labs boxes were a very fitting solution due to their low profiles and their exceptional directivity.” The goal was to keep energy on the congregants and off the walls.
Inputs to the system collect at an Allen & Heath GL2400-424 console, which outputs to a Xilica XP8080 digital loudspeaker management processor. In turn, the processor outputs to QSC RMX 4050HD and RMX 5050 amplifiers. Those QSC amplifiers power two Danley SM-80 loudspeakers that provide main coverage, six Danley SH-micro loudspeakers that serve as delays, and one more Danley SH-micro that fills in the center front.
“The SM-80s were ideal loudspeakers for the mains because they are so slim and could be mounted into the wall without any trouble,” said Ng. “Both the SM-80 and the SH-micro are highly directional, which was great for these low ceilings. The sound goes where it is supposed to go and nowhere else. Importantly, that directivity extends down to 400Hz. Moreover, the Danley tone is natural and not at all fatiguing.”
To provide low-end support for the system, Ng included two Danley TH-mini subwoofers, which the installers mounted into the front wall below the SM-80s.
“The TH-mini has to be the smallest but loudest sub I’ve ever heard,” he said. “The amount of bass coming out of this box when properly powered is nothing short of amazing. Subjectively, every bass note is tight and punchy.”
He continued, “All together, the new system is way, way better than the system they used at the hotel. Everything sounds clear, crisp, and pleasant to the ears, and it doesn’t matter where you sit. The whole room is evenly covered.
“Even when the microphones are placed right underneath the center fill Danley SH-micro, there is no feedback. Hanoi International Fellowship couldn’t be happier.”
Danley Sound Labs
D.A.S. Provides Pristine Sound Quality At Las Vegas Theater
Saxe Theater installs a new D.A.S. sound reinforcement system.
Located inside the Miracle Mile Shops of the Planet Hollywood Resort on the world famous Las Vegas Strip, the Saxe Theater is home to several of this town’s most popular shows.
The Saxe Theater recently upgraded their sound reinforcement capabilities by installing new D.A.S. Audio loudspeakers.
GC Pro was contracted to design and install the Saxe Theater’s new sound system. GC Pro Account Manager Don Hartley, working in conjunction with Jeff Pressler, head of audio for David Saxe Productions, designed a system that consisted of eight Aero 12A powered two-way, mid-high line array modules with additional support from a pair of Convert 12A powered two-way full range loudspeakers.
The Saxe Theater is uniquely laid out with a main area approximately 80 feet by 60 feet. There is also an upper seating area that is oddly shaped, measuring roughly 20 feet wide and stretching back 40 feet. The theater’s ceiling has an average height of 30 feet and the venue has a seating capacity of 420 people.
Because of the combination of the lower and upper level seating areas, it was critically important that the new loudspeaker system provide consistent sound throughout all areas of the room with, of course, a high level of speech intelligibility and strong music reproduction characteristics.
To address these concerns, Hartley and Pressler ultimately deployed the D.A.S. Aero 12A line array elements in a flown left – right configuration, with each side of the main stage area having four enclosures. The two Convert 12A loudspeakers were installed as rear fill for the upper level triangular area, which also resides behind the FOH mix position.
“The self-powered loudspeakers make a terrific solution for this type of venue,” Hartley elaborated. “The Aero 12A loudspeakers provide a very streamlined installation in terms of system cabling while also ensuring that all amplification is optimized for the transducer complement.”
With the D.A.S. Audio Aero 12A, the captive rigging system splay angles range from 0- to 10-degrees and can be adjusted in 0.5-degree increments from 0-degrees to 3-degrees and 1-degree increments from 3-degrees to 10-degrees —allowing a wide range of column curvatures to be created.
“The flyware on the Aero 12A loudspeakers is excellent,” Hartley reports. “The design makes it quick and easy to connect the various enclosures together and to adjust the pins to ensure the proper positioning of each individual enclosure. It’s a very well-designed system with great flexibility.”
“I’ve always been impressed with how informative and easy-to-reach D.A.S. Audio’s customer services team is,” Hartley continues. “I considered it very important that the loudspeaker provider have our backs throughout the entire design and installation process, and D.A.S. came through with flying colors.
“Carlos Henao, D.A.S. Audio’s U.S. Accounts Manager, was extremely helpful. He helped me set up a demonstration system for Jeff Pressler and his FOH engineer, Mariano and, later, came back to do a second demo at the theatre where multiple producers were able to hear how the system would sound. You can’t ask for more than that! ”
The Saxe Theater’s new sound system was deployed and placed into service this past June and since that time the system has been very well received.
“Our new D.A.S. sound system is performing wonderfully,” reports Pressler. “The Aero 12A line array covers the theatre evenly and sounds great in all applications. One show may use only a lapel mic while Vegas! the Show has 20 live pieces.
“This system can handle anything we throw at it. The Convert fill speakers do an equally impressive job in the upstairs area where some guests are 80 feet from the stage. Our new system provides a clean, full sound that really helps our shows deliver the excitement.”
DUSHOW Covers France’s Main Square Festival With Meyer Sound
LEO system on the festival’s main stage supported headliners such as Sting, Green Day and The Prodigy
At the recent Main Square Festival in Arras, France, Paris-based rental house DUSHOW supplied a Meyer Sound LEO linear large-scale system and a MILO line array loudspeaker system for the event’s two stages. The three-day festival attracted a total crowd of approximately 100,000.
The LEO system on the festival’s main stage supported headliners including Sting, Green Day, The Prodigy, and Indochine. With a maximum capacity of 30,000, the main stage field was fully covered by the LEO system’s long-throw capabilities.
“This system’s consistency of coverage and high output allowed us to avoid the need for delay towers, and to maintain sound integrity over the required distance of 110 meters,” says Marc de Fouquières, general manager of DUSHOW. “LEO’s excellent directivity also prevented conflict with audio from the second stage, which was located in parallel and only 100 meters away.”
The main stage was outfitted with 48 LEO-M line array loudspeakers and 32 1100-LFC low-frequency control elements, as well as eight each MICA and MINA line array loudspeakers and four MSL-4 loudspeakers. The system was controlled by a Galileo Callisto loudspeaker management system featuring seven Galileo Callisto array processors.
The Green Room stage featured 30 MILO line array loudspeakers and 24 700-HP subwoofers. System control was provided by a Galileo system with two Galileo 616 AES processors.
“As we have come to expect from Meyer Sound, the systems delivered superb and trouble-free sound throughout the weekend,” says de Fouquières. “We are delighted by the performance of our LEO systems.”
DUSHOW is the exclusive lighting, audio, video, and rigging supplier for Main Square Festival, a production of Live Nation France Festivals SAS, and the company recently purchased its second full LEO system in preparation for the busy summer festival season.
Fill-osophy: Fill Loudspeaker Types, Applications & Optimization
Filling holes and extending quality coverage
Whether a sound reinforcement system’s primary loudspeakers are point source clusters or line arrays, there may be a hole in coverage for the seats closest to those arrays.
Curved line arrays (J-arrays) may - or may not - allow the lowest elements to be aimed appropriately to cover these nearby seats. More traditional point source arrays can be just as tricky.
Simply throwing another box in at the bottom is not likely to provide the required coverage. Therefore, a dedicated down fill box is often the best candidate.
Several companies design and manufacture purpose-built down fill loudspeakers that fit with arrays and have rigging points to expedite their use. Many of these dedicated down fill boxes also provide asymmetrical coverage to better fit the required coverage area. These can perform very well and also present the cleanest appearance for both temporary and permanent installations.
Step By Step
Used almost exclusively for front fill in worship spaces, stair-step loudspeakers are designed to be flush mounted into the platform steps in an effort to reduce clutter and visibility. Many platform stairs present a reduced rise (6 inches, typically), which leaves very little height for such loudspeakers.
Most of the models I’ve evaluated with this small of a footprint simply do not have enough horsepower to reach the first rows at an appropriate volume level when the seating is spaced well away from the platform, which occurs frequently in larger modern worship spaces.
Down fill solutions that integrate into arrays/clusters from (left to right) Danley Sound Labs, Meyer Sound, and Tannoy.
Of equal concern is the low mounting height, which makes it very difficult to cover past the first row of seats. So do your homework and make informed decisions when you’re forced to consider this direction.
In permanent installations and visually sensitive events (corporate events, weddings, etc), it’s often a huge deal to conceal or minimize the appearance of the loudspeakers.
Fill loudspeakers can be cleverly concealed, but it’s up to us to ensure that their performance is not compromised by over-zealous designers or unrealistic clients.
Placing these loudspeakers in closets or behind fabric that is reflective or absorptive is perhaps the most frequently encountered proposed solution from those who have no awareness of the consequences.
We must employ diplomacy as well as our own experience and authority to ensure that the visibility of the loudspeakers are minimized but without compromising sound quality.
Base Design Considerations
As most of us are well aware, in live audio there are often consequences as well as the anticipated benefits to what we do and how we do it. It can safely be said that “nothing is as simple as it appears,” and fill loudspeaker design is no exception.
Perusing what is available as far as small-profile full-range fill loudspeakers clearly shows that dual woofers with a single high frequency element is the most widely used driver configuration for front fill, underbalcony fill, box seat fill, and so on.
This is necessary because a single small cone driver cannot keep up with a horn-loaded high-frequency device and will simply ‘run out of gas’ when pushed to the levels that are needed.
Two woofers couple at lower frequencies and produce more acoustic output. But how these woofers and the HF element are arranged, as well as how the two woofers are processed, have considerable impact on how these loudspeakers behave.
There are two choices for positioning the woofers: together with the HF element at one end or apart with the HF element in-between. In the hi-fi and home theater world, the latter is called MTM (mid-treble-mid) or the D’Apollito configuration. Logically, then, we will call the first configuration MMT (mid-mid-treble).
The MMT configuration results in less comb filtering from the two woofers because they are closer together. But the coverage across the horizontal axis (when these boxes are on their sides) will be uneven and asymmetrical.
At left, a Renkus-Heinz Synergy stair-step loudspeaker, and at right, we see a stair-step loudspeaker that’s probably mounted too low.
On the other hand, MTM provides symmetrical coverage across the horizontal axis, but also exhibits greater comb filtering. It’s possible to reduce the comb filtering simply by rolling off (with a low-pass filter) one of the two cone drivers so that they’re allowed to couple at low frequencies but do not destructively interfere (with one another and the HF device) at (and near) the crossover point.
There are quite a few of the full-range loudspeakers on the market where the coverage of the horn is not “axi-symmetric” (a.k.a., non-conical), and with HF horns that may be rotated to suit the orientation (application) of the device. But rotating the horn also alters lobing between (and coverage from) the LF and HF elements - and this may not be to our benefit.
A small number of these loudspeakers are provided with a passive compensating network which may be engaged for each of the two horn orientations. Warning: read the spec sheets (before buying) and always check the horn orientation.
Fill Versus Boundary
When mounting underbalcony fill loudspeakers we often place them up against the balcony ceiling and angle them downwards to cover the target sets.
In doing so we create a cavity with a closed back. The diffracted energy from the loudspeaker, which wraps back into this cavity, is projected back out where it combines with the directly radiated energy.
At the same time, the slightly off-axis energy projecting from the loudspeaker reflects off the ceiling and combines with the directly radiated energy. The arrival time differentials at the listeners’ ears from these two unintended side-effects can create a notch in the frequency response (from the cavity) and smeared MF and HF response (from the reflections). Both of these are audible and measurable.
In any area where we apply fill loudspeakers we must be alert to the surrounding architectural conditions to ensure that the potential for such unexpected side effects are at least considered, even if it turns out we cannot completely address them.
Measurement & Optimization
In almost all cases, fill loudspeakers have very little impact on the performance of the primary and other fill loudspeakers. This is due to several factors including the limited area they cover, the low acoustic output required from them, the distances between one system and the other, and the isolation frequently provided by architecture.
Most fill systems simply do not “register” when one is listening to (or measuring) the primary clusters. Specifically, while measuring the primary loudspeakers when the fill loudspeakers are turned on and off, there is almost always no aural (perceived) or measured change from within the seating covered by the primary speakers.
Obviously, the primary loudspeakers do impact the seats covered by the fill loudspeakers, and this occurs mostly at middle and lower frequencies.
When measuring and optimizing fill systems, we focus almost entirely on alignment, level and equalization relative to the primary loudspeakers. If we’re lucky (and/or have the clout), we can select the most appropriate fill loudspeakers, locate them exactly where needed, conceal them (or reduce their visibility), and painstakingly apply measurement and optimization.
At left are two MMT (mid-mid-treble) loudspeakers, and at right, two MTM (mid-treble-mid) loudspeakers.
When all of these ducks are in a row the result is that every seat has great sound and the fill loudspeakers work so well that they may even appear to not be on. When muted there is a very clear difference.
Most folks know all too well that touring and one-off show productions barely allow enough time for thorough measurement and optimization of the primary loudspeakers and stage monitor systems. So setting up and optimizing fill loudspeakers is rarely possible.
Competition with the other trades/disciplines, along with the very limited time available for everything to be set up, dictates that we simply do the best that we can.
Although this often may be good enough for the audiences at such shows, we must be aware that completely ignoring the destructive interactions that occur and doing nothing about them yields compromised sound quality.
In particular, sources with percussive elements can get lost at times or (in some cases) are simply not audible at all. And intelligibility takes a big hit.
Exceptions to the above “rule” are the bus and truck tours of Broadway shows as well as corporate events where the loudspeaker systems are more carefully designed.
Further, the sound crew is allowed more time to optimize the performance of the loudspeakers, including localization.
A complete discussion of alignment philosophies cannot be thoroughly covered within the confines of this article. Many sound system technicians, designers and contractors employ additional delay for the purpose of moving the fill loudspeaker energy behind the primary source energy.
The Haas and Precedence effects are the theoretical justification for this but (in this case) are incorrectly applied. Such misalignment degrades coherence and therefore intelligibility, and is also simply unnecessary for maintaining localization.
Tom Young is the principal consultant at Electroacoustic Design Services with both worship and performance space projects in and around New York City and throughout New England. EDS specializes in sound reinforcement system design, loudspeaker system measurement and optimization, acoustic design and noise reduction.