3D rendering of the setup for Arvo Pärt at Eighty in The Temple of Dendur, September 2015. Photo courtesy of Kwabena Slaughter
When there's a performance in one of The Met's galleries, there is a lot of behind-the-scenes planning and rehearsals that occur before the artist even takes the stage. Often I've heard audiences exclaim how wonderful the musicians sound in the galleries, and how surprisingly conducive these spaces are to live music. That's a compliment we'll gladly take, but the truth is . . . that crisp audio heard throughout the Museum's grand spaces is the result of careful planning, the proper installation of sound equipment, and the precision of the MetLiveArts production team.
The 2016–17 season of MetLiveArts programming begins this Friday, September 9, with the brilliant Ethiopian jazz musician Mulatu Astatke in The Temple of Dendur, so this is the perfect moment to check in with Associate General Manager of Production and Venue Operations Kwabena Slaughter to discuss the technical aspects of these in-gallery performances, and especially how the team masters the audio. Here's a quick look into the process of turning (and, in this case, tuning) these challenging galleries into superb concert spaces.
Meryl Cates: When did you create the tech renderings for the Mulatu Astatke concert?
Kwabena Slaughter: We make 2D CAD [computer-aided design] drawings for all of our projects in the galleries; it's a top-down plan view. For unique setups that have never occurred before, we'll make a 3D drawing to make it as easy as possible for people to understand where equipment will be and how it will look. Since the Mulatu concert is in a layout that's happened many times before, we only made the 2D drawing.
2D drawing of the setup for Mulatu Astatke in The Temple of Dendur, September 2016. Photo courtesy of Kwabena Slaughter
Meryl Cates: How closely do you work with the curatorial departments and their technicians? Does it depend on the performance, or is the process the same for every show?
Kwabena Slaughter: We sit down with curatorial representatives to discuss ideas, look over the 2D drawings, and talk about the performers and the value of presenting them in the specific gallery. We are in constant communication with the art technicians during the setup, show, and strike. Sometimes the musicians ask for the location of something to change, so we talk with them about options.
Meryl Cates: When do you actually get into the gallery and start installing?
Kwabena Slaughter: Usually we are in the gallery only on the day of the show. We will move any equipment that has to go from the [Grace Rainey Rogers] Auditorium's backstage area between 9 am and 10 am, so that we're done before the Museum opens to the public. The items that we rent for the show—lights, power cables, sound equipment, jib cameras, audience chairs—are loaded in via freight elevators. We try to complete the setup by 2 pm so that the musicians can rehearse.
Meryl Cates: Each space and gallery is different, but what goes into making The Temple of Dendur such a great performance space?
Kwabena Slaughter: Electricity. Spaces designed to host events will have a high-amperage, three-phase electrical service somewhere onsite. The Temple has something like 1800Amps available; an average theatrical light draws 7Amps, so there is an opportunity to use a lot of lights in there. The combination of the historic antiquity that is the Temple and the availability of plenty of electricity is a large part of what makes it a great space for a performance.
The gallery has a glass north wall, a glass ceiling, and every other surface is stone, so any one sound will bounce around the room in many different directions before decaying into silence. A concert that is supposed to sound unamplified, like a string quartet, still needs amplification in Dendur simply to overcome the muddiness of all the sounds reflecting off all the walls. Imagine that a musician is making sounds on the up and down beats: "one-and-two-and-three-and-four-and." Because of all the reflections of sound off the floor and walls, however, the audience will actually hear: "One-and-two-and-and-three-and-four-five-and."
Various acoustical problems exist in most of the galleries because the majority of them have hard surfaces for the floor and the walls. The first step in solving these issues is to use more speakers than would be used in a theater, and to operate them all at lower volume. To be able to power these additional speakers, we need more electricity, which the Dendur gallery was built to provide.
The next step is what's called "tuning the room." We play white noise through the speakers, use a mic to listen to the reflections of the sound off the walls and floor, and that mic feeds into computer software that identifies the frequencies that the mic is hearing. With that knowledge we can use the sound control board's equalizer to remove certain problem frequencies from the audio that is playing out of the speakers. Sometimes if you listened to that mix in headphones it would sound very weird, but in the room it sounds perfect.
Meryl Cates: Audio-wise, what has been the most challenging concert that you and the team have worked on over the past couple of seasons?
Kwabena Slaughter: The Civilians in Dendur [for their 2015 performance The End and the Beginning] was a challenging audio setup because we had four different sound systems. The actors were in different locations around the room and the audience would move from one location to another. We had to tune each system based upon the direction the speakers were facing.
The first time we produced Arvo Pärt's Kanon Pokajanen was also a challenge because the 26 singers were in a circle facing one another, so we tried to set up the PA system behind the audience so that they would have the feeling of being inside the circle of singers. Lang Lang in the Great Hall was another tough one. We used only four speakers for that, which served an audience of 500. That was really about amplifying the least amount possible, but enough to clarify the sound and overcome the acoustical reflections.
The Civilians Perform The End and the Beginning in The Temple of Dendur, March 2015. Photo by Paula Lobo
Meryl Cates: Because the Temple and surrounding galleries contain artwork, I know there are audio considerations made around the artifacts. Can you explain that process a little?
Kwabena Slaughter: We have to talk about volume and vibrations as two separate things. Most people have seen that video where a soprano opera singer sings into a telephone and at the other end of the phone call there's a wine glass that breaks because the singer is so loud and the telephone line is so clear. That's simply fiction designed to get you to switch telephone service providers.
In a concert environment the first thing that a sound frequency will vibrate is the speaker cabinet from which the music is coming out. This is why, for effect, many places put the bass speakers on the floor, as they want the speaker cabinet to make the floor vibrate. If you're standing or sitting on the floor you will also vibrate, and maybe dance. The primary action to stop this type of vibration is to lift the speaker off the floor, or put dampening fabric or rubber between the speaker and the floor. With that move alone the majority of the issue is solved.
The concern around art objects is that the sound will cause vibrations in the shelf on which the object sits, which could cause the object to slowly walk itself off the shelf. So by taking the speaker out of physical contact with the floor, or walls, or shelf that houses the art, this concern is mostly resolved.
If we're talking about vibrations caused simply through the air, the volume at which the vibrations can occur differ for each frequency and differ depending on the speaker position. Let's imagine a concert consists of a range of frequencies from 50Hz to 20kHz; a particular placement of a speaker could result in the 1kHz frequency causing an object to vibrate. If that frequency can be removed via the equalizer, then the other frequencies can play at a loud volume without incident. This is a large part of the value of tuning a room—it tells you which frequencies the room's acoustics will boost, and which it will limit.
Meryl Cates: Breakdown and load-out begins as soon as the concert is over and the audience is cleared. How long are you usually in the galleries after the concert is over? Meaning, until you walk out and have returned the gallery to its regular state.
Kwabena Slaughter: For a full-scale concert like Mulatu Astatke, it will take about 2.5 hours.
The Mulatu Astatke event is sold out, but to purchase tickets to the next performance in The Temple of Dendur, Arvo Part: Kanon Pokajanen, or any other MetLiveArts event, visit www.metmuseum.org/tickets; call 212-570-3949; or stop by the Great Hall Box Office, open Monday–Saturday, 10:30 am–3:30 pm.
Related Links
MetLiveArts Blog: Meryl Cates, "Performances in The Met's Galleries—Then and Now" (July 11, 2016)
MetMedia: Arvo Pärt at Eighty (Recorded September 11, 2015)