Careful planning overcomes acoustic challenges for Mellencamp concert.
Visually, the West Baden Springs Hotel in Southern Indiana is about as magnificent a venue for a corporate event as you could hope to find. Completed in 1902, the historic building features a six-story, clear-span, domed atrium that is dazzling in its architectural beauty. During its glory days, the hotel once served as a posh, 700-room resort that attracted politicians, athletes, and such colorful figures as “Diamond Jim” Brady and Al Capone.
But as visually stunning as it is, the giant atrium can be technically challenging for staging professionals, especially if the event features a significant audio component. Not only does the domed space behave like an echo chamber, but because the building is an historical landmark, staging companies working there must adhere to strict rules and regulations.
Given those realities, when Mark Dodd, president of Dodd Technologies, Indianapolis, was asked to stage an awards show for 2,000 employees of medical device developer Cook Group Inc., Bloomington, Ind., at the hotel, featuring a live rock show from John Mellencamp, he knew the event would require careful planning.
“This is about as unfriendly an acoustic environment as I've ever seen,” Dodd explains. “The space is about 200ft. across, and the dome is all steel. The floor is completely tiled, and the wall surface around the outside is all plastered glass. There are some places on the floor where the sound is so distorted, it almost becomes impossible just to hold a conversation.”
In addition, when moving equipment in and out of the building, workers had to operate with extreme care.
“[Historic Landmarks Foundation of Indiana], which manages the property, pretty much follows you around with a broom, and if you knock a chip out of anything, you'll have to answer for it,” says Dodd. “You can't just roll cases wherever you want. You have to be extremely delicate. The floor in this building was completely rebuilt, and it's unique. So you have to pad everything.”
Because the rules don't permit crews to hang anything from the domed ceiling, Dodd also had to bring in a self-supporting, Thomas-style staging system.
“For this particular event we built a six-tower roof stage,” Dodd explains. “We didn't put the roof skins on, but we used the supports to get the lighting in the air and get the video screens out. We built a four-poster roof, and then a pair of wings for the video screens, and we hung the sound the same way. The posts that supported the video screens also supported the sound arrays.”
For video, Dodd placed two 15'×20' screens on each side of the stage, and used double-stacked Sanyo 10,000-lumen PLC-XF45 projectors to provide the imagery. For the most part, the screens were used to display IMAG, fed from a Sony D35 analog component camera.
The real challenge, however, was figuring out how to handle the sound. Dodd had staged events for Cook Inc. in the West Baden Springs Hotel before, and was well familiar with the acoustic challenges. He'd previously tried different strategies to cope with the problem, though he hadn't been particularly satisfied with any of them.
In the past, Dodd says he had used distributed audio systems at the venue. “We've had engineers who felt that if they just put enough sound in there, they could outrun the space, but it's really not doable. The intelligibility goes away very rapidly, and then it is just plain loud.”
With Mellencamp's loud rock show coming in, however, Dodd knew he'd need another solution.
Part of that solution was to utilize a line-array audio system — specifically, a mid-size XLC Electro-Voice line array with Crown power and XGA processors on the front end.
“It was the first time we tried using a line-array system in there with no delays, and a key reason it worked so well is that we had a much better ability to steer that system so that we weren't hitting the walls more than we had to,” says Dodd. “It doesn't help you in the low end, but it certainly helps you in all the mid-band and up frequencies.”
The other part of the solution involved treating the walls of the atrium with sound-absorbing fabric. Getting permission to do that, however, wasn't easy.
“The historical society usually won't let you do treatments, because they feel one of the reasons people come to the hotel is because the space is so architecturally beautiful,” says Dodd. But with Mellencamp, Dodd knew treatment of the space was essential.
To get the necessary permission, Dodd turned to Bill Cook, founder and chairman of Cook Group. Knowing that the company had donated a great deal of money to aid in the renovation of the hotel, Dodd hoped Cook could get the officials to relax their rules this time.
“I told him, you have to trade off some on the appearance of the space if you want John Mellencamp to perform at his best, and you want the audience to get anything from that performance,” recalls Dodd. “I explained that if we couldn't do some acoustic control, it was going to be a very long 90 minutes.”
Dodd eventually received a go-ahead, allowing him to cover the walls of the atrium with 25,000 yards of pleated drapes. In hanging the drapes, Dodd was careful to position them in such a way as to preserve at least some of the architectural beauty of the space. The drapes were cut in sections, each about six stories in length and hung between the large pillars that ringed the atrium. Leaving the pillars and the domed roof exposed helped keep the feel of the space alive.
The drapes also stopped 10ft. off the floor, so that all walls at eye-level, including the exits and entrances, were left uncovered.
While the drapes made a huge difference in the absorption of high-frequency sounds, Dodd also decided to open the doors of all the hotel rooms that faced outward toward the atrium floor. The top five floors of doors that were located behind the drapes led to rooms that had not yet been renovated. These large, unfinished spaces, says Dodd, served as large traps to capture and dissipate a lot of the low-frequency energy generated by the concert.
“By doing that, we essentially got to use the drapes twice,” Dodd explains. “We had energy dissipation as the energy went through the drapes to go into the rooms where it bounced around those empty cavities. Then we caught it again as it tried to come back out of those areas.”
The result, he says, was a huge improvement in sound quality. Even before Mellencamp played his first note, Dodd says attendees at the event commented how the sound absorption strategies improved just casual conversation in the room.
As for the quality of the concert sound, Dodd says both Mellencamp and the audience were pleased, a fact confirmed by Mellencamp's tour manager, Rocky Holman. “We almost always specify our own production for these types of events,” he said. “You take a big risk when using outside vendors. But I was pleasantly surprised. Everything worked. They did what they said they would, and the work was done quickly and efficiently. I love it when a plan comes through.”
Stephen Porter is a freelance writer who has been covering video, graphics, and digital content creation technologies and applications for more than 15 years. Email him at firstname.lastname@example.org