Releasing the music in the Golden Gate Bridge
21 Mar 2012
Making sound art with accelerometers, charge amplifiers and microphones, Bill Fontana enhances our perception of sounds by revealing how structures hum with an unseen rhythm of life.
|San Francisco's famous bridge looks almost like a harp as it stands shrouded in the fog|
Using accelerometers, microphones, speakers and amplifiers for uses that their designers surely never foresaw, Bill Fontana has been making sound art since the 1970s. Trained as a composer, he soon found an interest in the physics of sound, and in the music inherent in the sounds of everyday life, as well as the developing world of modern music that uses sounds created with technological means. Since then, his innovative vision has become internationally renowned through critically acclaimed installations all around the world. Big Ben, the Brooklyn Bridge, and the Arc de Triomphe are just some of the celebrated locations to have had their pulses felt by Bill as he sets out to show us the music that exists within both structures and everyday sounds.
In 2006, London’s Millennium Bridge became the focus of Bill’s work, when he worked alongside the bridge’s constructors – Arup Engineering – to place Brüel & Kjær accelerometers all over the structure. Entitled ‘Harmonic Bridge’, Bill’s work used the way that the bridge’s unique, flexible structure oscillated and vibrated in its many different modes to create an enormous musical instrument. Next to the bridge stands the monolithic Tate Modern art gallery, and here, in the enormous Turbine Hall the accelerometer signals were replayed as audio output – after judicious tweaking with a digital signal processor. The effect thrilled its creator and millions of spectators alike.
Playing on a footbridge
|After training as a composer in the 1970s, Bill Fontana went on to become a pioneer of sound art|
“The bridge was alive with vibrations caused by its responses to the collective energies of footsteps, vibrations and wind,” says Bill. “You can’t normally hear it, but it’s revealed by accelerometers that are placed all over the bridge to map in real-time its hidden musical life.” This live sonic mapping was then translated into a living sculpture by rendering sounds into a spatial matrix of loudspeakers, with the goal of showing what’s already there rather than altering the sound too much. As he says, “It’s more like I’m bringing something that’s alive out into the world, and the less of me and the more of it, the better.”
“It made beautiful sounds as it reacted to wind,” continues Bill, “With the people walking on it and so on, and the fact it had previously had problems with its structural dynamics just made it more interesting.”
|“My favourite Brüel & Kjær product is a charge amplifier … the front panel is so precise that it is possible to very accurately alter the sound in very fine adjustments. You have a great deal of control”|Perhaps the inner life of structures is an unusual choice for a musician, but for Bill it was something of a logical progression from an early interest in the sounds that we hear every day. “Hearing sounds around me became as interesting and beautiful as listening to music. I came to regard the act of listening as a creative activity – finding music in the environment around me,” he says. But it is not just about good vibrations though, as studio microphones and hydrophones have played important parts in most of his works. In his 2010 work ‘River Soundings’, he took sounds from the River Thames and played them inside London’s nearby cultural centre Somerset House. And on another occasion he filled the rotunda of the San Francisco City Hall with a mixture of mid-range sounds like birds, trams and water, using ultrasonic emitters to beam them around with great accuracy, and making people appreciate them in a whole new way.
|Accelerometers on London's Millennium Bridge track its dynamic vibrations - only to replay them as sound in the adjacent Tate Modern gallery|
With accelerometers though, you can discover the inner life of structures. “And that,” says Bill, “Is really what interests me and what my work is about. All of the solid things you see, all of those materials, if you could enter those solid things you could see that those materials are actually, within themselves, vibrating. So I’m interested in entering into that dimension of materiality.”
In Japan there are some famous temples in Kyoto where some enormous, 1000-year-old bells drew the unusual attention of Bill. “I was interested to see if they make any sounds when they are not ringing,” he says. Attaching accelerometers with beeswax revealed that they are in fact vibrating all the time. “It’s actually an elastic material that reacts to the sound energy of the garden around it,” says Bill. “It’s not a sound you can hear standing next to it, so for all you know it’s silent, but put on an accelerometer and you enter a hidden world.”
“I regard sound as vibration in any solid material – be it water or solid,” he continues, “so I am trying to get inside the structure to look at that inner world. So to me, the accelerometer is a very important tool.”
The Golden Gate Bridge
|“Putting an accelerometer on either side of an expansion joint on the bridge sounds great, almost like something that chimes”|
Speaking in February 2012, Bill was beginning work on the next great creation, wiring up San Francisco’s vast landmark with accelerometers to celebrate its 75th anniversary. When his installation ‘opens’ in May this year, it will be Bill’s second project featuring the famous bridge. The first, in 1981, was a live replay of sounds like deep, booming foghorns from different parts of the bridge, as well as a nearby seabird refuge. This time though, he’s more interested in the vibrations. “I really want to release that inner sound,” he says. “I have been climbing all over the bridge with some signal analyzers and having fun testing it out for the installation. It’s an alive structure, and tapping into that is very exciting. Putting an accelerometer on either side of an expansion joint on the bridge sounds great, almost like something that chimes.”
Brüel & Kjær
|His latest project sees Bill crawling all over the Golden Gate Bridge with a Charge Amplifier Type 2635|
“My favourite Brüel & Kjær product is a charge amplifier,” says Bill. “It runs on batteries when necessary, and I like that when you connect a charge accelerometer to it you have so much control over the accelerometers.” Alongside plenty of other equipment, his Charge Amplifier Type 2635 stands out due to the great control it gives over the signal you get. With input for transducers like accelerometers or hydrophones, and an audio output, it can connect structures to a variety of reproduction sources. “The charge amplifier’s front panel is so precise that it is possible to very accurately alter the sound in very fine adjustments. You have a great deal of control,” he says.
Over the years, Brüel & Kjær equipment has made an appearance everywhere that Bill’s projects have. In addition to the aforementioned hardware, he has used Brüel & Kjær Hydrophones Types 8103 and 8104, as well as some Type 4006 studio microphones bought in 1991. “When making initial field recordings and site surveys I use the charge amplifier with a charge accelerometer like the Type 4379,” says Bill, “However, I generally use piezoelectric accelerometers for live installations.”
So what about value-adding technologies like REq-X, Dyn-X, TEDS and so on? Well, while aware of TEDS, such technologies hold little interest for Bill, for whom precise data is of less interest than most users. Or in other words, he doesn’t really mind which transducer is making which sound! More important is to get the noise out, into the light of day.
Discombobulating the non-listeners
|Accelerometers help transcend the limitations of time and space, providing listeners with a sound of Big Ben like none they have heard before|
We all learn to listen conditionally. We categorise sounds into unwanted ‘noise’ and desirable music – and many categories in-between. Unwanted sounds – which are most – we ‘zone out’. And for Bill, this is not necessarily a good skill to have. “I think our culture is in many ways acoustically illiterate, in that people don't grow up learning and recognising or even paying attention to sound patterns in what they would call noise," he says.
For Bill, eliciting insights in people’s acoustic perceptions is the goal, and dislocation is a great way to achieve it. "We learn not to listen by visual cues. If you walk down a street, you're not going to listen to the traffic, but if you heard a recording of the traffic in the woods, you would listen,” says Bill. “So the eyes can switch off the ears, and I like to defeat that mechanism." As such, his projects are experiments in perception, designed to break down the general habits of ‘non-listening’.
As Bill’s own artistic hero, the legendary avant-garde composer John Cage said, “Music is continuous and only stops when we turn away and stop listening.” In other words, if a tree falls over in the woods and there is no-one there to hear it, it not only still makes a sound, but it makes an interesting and possibly musical one.
What is the true nature of a sound?
“A sound is all the ways there are to hear it” is a quote often ascribed to Bill, and if you find that confusing then fear not, for he is a pedagogic man who likes to use concrete examples to illustrate the concepts he wants to convey.
“I did a project in London in 2008 called ‘Speeds of Time’ that illustrates this idea,” says Bill. “If you think of the sound of Big Ben, the bell rings when you stand next to it. So is that the ‘right’ sound of the object? But then, what if you go on the rooftop, is that the right sound? What about if you are 1000 feet away and the delay affects the sound, is that the right sound? What’s the correct sound, and what’s the correct time? I want to show a composite of the sound from all these different ways there are to hear it. Showing these things all at the same time is the real sound of the bell, which is possible through the use of technology.”
Another example was when he installed microphones at a series of railway level-crossings. Trains have to blow their air-horns before they cross them, so he was able to record the effects of Doppler shift as the trains approached and left the crossings, with the pitch rising and falling. “Hearing these all together gave a really interesting harmonica effect,” says Bill, “and it was only possible through the technology – as we don’t have an octopus-like array of ears to hear all the sounds at different locations simultaneously.”
So what’s up next for the modal maestro, once the Golden Gate Bridge has finally given up its secret sounds? “Well as a matter of fact, I just read an article in the New York Times about a bridge that is being rebuilt – the ‘Bay Bridge’ in San Francisco,” says Bill. “This bridge is designed to sway in an earthquake, which sounds really interesting, so I might start looking at that next.”
Follow Bill at resoundings.org
Read the latest industry news