The new City Performance Hall in Dallas’ Arts District debuts this Friday with an evening of live music. But before the concerts and opening ceremonies, the hall’s acoustics are being measured and tested. KERA’s Jerome Weeks checks in with the people checking out the hall’s sound.
- KERA radio story:
The acoustics of any performance hall are key to its success. Look at — or listen to — the Meyerson Symphony Center. But the Meyerson was designed primarily for symphony concerts. That’s what it does. The new City Performance Hall, in contrast, is at the other extreme. It will have to accommodate everything from jazz groups and lecture series to dance companies.
[sounds of stepping and panting from workers]
One way it’ll do that is up here, in the attic of the new hall. We’re climbing over pipes and I-beams on a steeply sloping floor that is essentially the roof of the auditorium beneath us. In the side walls of the attic are shallow alcoves, like cupboards (below, left). These house the motorized winches and cables that physically raise and lower the hall’s acoustic banners. The banners are thirteen, long, grey curtains that drape down the walls in the auditorium below.
Patrick Surratt is the project manager for Texas Scenic Company which built and installed the banners (above).
[Flipping switches. “We’ll do a quick test run.” Motor starts up and whirs throughout the following.]
Surratt: “They’re two layers of serge wool fabric, about four inches apart. They basically cut down the reverberation.”
[“’OK.” Motor switches off. ]
Acoustic banners like this are not that unusual. Texas Scenic Company has installed similar ones in Commerce and Austin, although these in the Performance Hall — the longest at 63 feet in length — are some of the tallest in North America. The banners will help adjust the sound in the hall by dampening the echoes that come off the concrete walls. A concert hall with bare concrete walls is relatively unusual, so cutting down echoes will be welcome when a rock band’s playing at the CPH. On the other hand, when it’s a chamber group that isn’t amplified, the hall has a wooden orchestra shell that can be set up onstage to help focus and direct the music at the audience.
But there are a lot of variables to fiddle with here. How many banners should be deployed for, say, a movie screening? Just the ones on the back wall? What will the sound be like when musicians are in the orchestra pit? Will stage performances need to be amplified?
Carlos Rivera is seeking to answer these and other questions. He’s the acoustic consultant with Jaffe Holden Technologies who’s worked on the hall since it was being designed. Today, he’s holding in his hand what’s known as a Larson Davis 824, real-time analyzer, a high-tech sound meter. He’s got some low-tech tools as well [sounds of hand pump].
Fifteen large balloons. Which he’s inflating.
Jerome: “You were saying this is the hardest part of your job?”
Rivera [continuing to pump the balloon]: “Absolutely, yeah. Manually pumping 17-inch diameter balloons, it takes roughly 130 pumps to get it to where I think it’s close to capacity without exploding in my hands. ”
These aren’t the kind of balloons you can get at yout typical party store. They’re bigger, with thicker vinyl. Rivera wants the balloon to explode, but only when he can measure the room’s acoustic response.
Like – now.
[BANG. Jerome: “That is loud.” Rivera: “Yeah.”]
In fact, the balloon pop clocks in at more than 100 decibels. If you could sustain that bang, it’d be as loud as many rock bands. Which is why Rivera wears hearing protection.But why a balloon pop in the first place? Presumably, the hall won’t be booking many shows with clowns running around exploding balloons all over the place. Why not play a tone from a musical instrument?
Rivera: “This is a repeatable thing. It’s a clean, impulse type of noise. And it works well from the low frequencies up to the high frequencies. It doesn’t vary.”
For a symphony orchestra, the optimum reverberation time in a hall is around two seconds, two point two. That’s how long it takes for all the sound to bounce around the room and get picked up by the human ear. Rivera says such a long reverberation lends a hall a warm, enveloping sense. And that reverberation time (RT) is close to what older European halls sound like, the halls many classical composers originally wrote for in the 18th and 19th centuries. So it’s the RT to shoot for if contemporary orchestras want to replicate that sound.
It’s true that big, old, medieval cathedrals have longer reverberation times, even more than double that. But that’s one reason medieval church music — Gregorian chants, pipe organ ditties — aren’t exactly speedy. The music is full of long, sustained notes. They’re waiting for that sound decay and resonating echo. Play too fast, play too many notes, and you get a muddle.
So too much reverberation makes it hard to distinguish instruments, individual notes or singer’s words, especially if the music is fast and loud. That’s why, when the band onstage is amplified at the CPH, the acoustic banners will get deployed.
The fact is, at the moment, the Performance Hall’s acoustic response is very lively, even with the banners down. Rivera says one reason are the hall’s 750 seat cushions. They’re leather, meaning they bounce sound more than the typical plush, velvety seats in a concert facility like the Meyerson.
But that also means a major factor shaping the sound in the new hall will be us. The audience. When it comes to sound, human beings are generally soft and absorbent. But with the CPH, the acoustic difference between an empty hall and a populated one is likely to be much bigger than usual because of those sound-bouncing seats. With all the seats filled, we’ll be like the acoustic banners, helping to dampen the sound.
So testing the new City Performance Hall won’t stop when it opens. Fine-tuning will continue.
Rivera: “OK, so here goes balloon number two.”
Grand Opening Schedule
- Thursday, September 13
11 am – Ribbon-cutting ceremony, followed by tour
6 pm – Panel discussion with the architecture team.
Evening – Hall to remain open for public tours
- Friday, September 14
- Saturday, September 15
Noon-6 pm – Community Open House, free to the public
All day – Food trucks parked near Dallas City Performance Hall
- 10:30 a.m. – Dallas Children’s Theater’s National Touring Company presents The True Story of The 3 Little Pigs. Hall Stage.
- 11 a.m. – Cara Mia Theatre Co. presents Payasos Clown full of hilarious surprises. Hall Stage.
- 11 a.m. – Junior Players present scenes from Shakespeare’sTaming of the Shrew. Hall Lobby.
- 12 p.m. – Interactive Improv with Jeff Swearingen from Fun House Theatre and Film. Hall Lobby.
- 1-1:30 p.m. – Dance Council of North Texas presents a showcase of Dallas-area dance troupes, including Dallas Ballet Company, Beckles Dancing Company, Contemporary Ballet Dallas, Elledanceworks and Southern Methodist University Dance Division. Hall Stage.
- 1:30-2 p.m. – Dance Council of North Texas African American Dance Class (Moussa Diabate). Hall Lobby.
- 2 p.m. Indian Cultural Heritage Foundation performs Nutana – New and Refreshing. Hall Stage.
- 2:30 p.m. – Shakespeare Dallas presents Speak the Speech: Shakespeare and the Spoken Word. Hall Lobby.
- 3-3:30 p.m. – Gocha & Shorena Center of Dance, Estudio Flamenco, Rythmic Souls, Indian Cultural Heritage Foundation and ICE Polynesian Dance Troupe performance, produced by the Dance Council of North Texas. Hall Stage.
- 3:30 p.m. – Sherna Armstrong presents Awesome Arias. Hall Lobby.
- 4 p.m. — Mitotiliztli Yaoyollohtli. Aztec dance performance.
- 4:30-5 p.m. – Latin Dallas Community Class presented by United Dance Academy. Hall Lobby.
- Sunday, September 16
Noon-6 pm – Community Open House, free to the public
All day – Food trucks parked near Dallas City Performance Hall.
- 12 p.m. – Le Theatre de Marionette presents a fun-filled medley of familiar tunes featuring marionette puppets. Hall Stage.
- 12:15 p.m. — Mariachi Quetzal. Hall Lobby.
- 1 p.m. – Orchestra of New Spain presents Baroque Music of Latin America. Hall Stage.
- 2 p.m. – Jason Davis Jazz performance. Hall Stage.
- 2:30 p.m. – Orchestra New Spain w/DISD Summer Strings. Hall Lobby.
- 3 p.m. – Lone Star Wind Orchestra. Hall Stage.
- 3:30 p.m. – Maharlika Dancers. Hall Lobby. Glimpse of the Philippines – Traditional Dances from the Philippines.
- 4 p.m. – Dallas Chamber Symphony Performance. Hall Stage.
- 4:30 p.m. – Dallas Chamber Symphony presents So You Think You Can Conduct: Eine Kleine Nachtmusik a lighthearted intro to conducting and symphony offerings. Hall Lobby.
- 5 p.m. – Metropolitan Winds performs American Band Traditions with a wind symphony of more than 63 musicians. Hall Stage.
- 6 p.m. – The Women’s Chorus of Dallas. Hall Stage.
Some events/performances subject to change.