In 2006, Éric La Casa put out a collection of recordings with an unusual concept. Fascinated by the ventilation systems that circulate air through modern buildings, he set about collecting audio from air ducts around town. He recorded thirty different samples, adjusted their volume levels to keep their loudness standard, and collected them on this CD in two minute intervals.
In the process of producing AIR.ratio, La Casa became an expert in the very contemporary phenomenon of mechanical air circulation. Via email, he tells me about how he developed his obsession with ventilation — and what went into creating AIR.ratio, which I suspect is the first album made entirely out of air duct recordings.
“Since my arrival in Paris in the early nineties, I lived in a Haussman-style building,” La Casa explains, referring to the big, cut-stone edifices created in the mid-19th century. “My daily life was that of a Parisian citizen whose indoors life was not governed by the standards of the end of the 20th century. The insulation in my apartment was as uncertain as the ventilation. The window was my only access to outside light and air. But the walls themselves seemed to breathe.”
But one day in 1994, he found himself in a friend’s modern bathroom, where his attention shifted to the air vent above the bathtub. “One of my friends had just rented an apartment in a building built in the eighties,” he tells me. While visiting that friend, he realized how much of everyday life is governed by industrial design. “The door code, the elevator, and even mechanical ventilation had become germane to life in Paris. All of this had become the standard of living,” he says.
“The elevator and the ventilation caught my attention very quickly. I have always appreciated the relationship between sound and space: how sound is diffused and how it informs me about the design of the environment. My awareness of mechanical ventilation in someone’s home was like a brutal shock. I was discovering that architecture could allow rooms to exist that don’t have windows. And in my friend’s bathroom, when I closed the door for the first time, I’m in the dark, with a constant sound that I don’t immediately think of as mechanical ventilation.
“And then, I rapidly became interested in all those Parisian rooms, public or private, without windows, which owe their survival to ventilation. And I was struck by the fact that each room has its own sonic identity due to the sound of the air extractor and the aeraulic system.”
That was in 1994. In the year 2000, he decided to start recording these vents. At the time, he didn’t have a final project in mind. “By dint of recording, and constantly being drawn to these air devices, I ended up with my final project. For over a year I did nothing more than that.” Today, he figures he created AIR.ratio to expunge himself of his air duct obsession; he figures he could have become pigeonholed as an artists who focused exclusively on ventilation systems. “But this is not my artistic endeavor,” he reflects.
Making the recordings in public spaces posed its own challenge. He attached two condenser microphones to a boom and held them up to vents and air conditioning conduits. They had to be suspended in the air, not quite touching the vents.
It turns out that it wasn’t easy to convince everyone about the goals of his recording, though many did seem receptive. “I often received a warm welcome when I explained the importance of the sound dimension in their interiors,” La Casa recalls. “But most of the time, I didn’t have permission to record, and had to sneak in with my equipment. Fortunately, the world was not as safe as it is today… I often arrived with my equipment completely dismantled and had to put everything back together quickly without attracting outside attention. And when you are in a toilet, installing equipment, quietly, it creates a bit of a weird situation with ordinary public toilet users. I often found myself in a washroom listening to a ventilator that sounded astonishing but but barely perceptible, while people waited to get in… before giving up.”
The disc collects two minute samples of each recording, each one identified by its specific location. Locations include a hospital, library, art gallery, and apartment. La Casa explains that bathrooms were often the easiest places to record to avoid drawing too much attention.
La Casa has thought deeply about ventilation systems. At one point, he hosted a radio show where he met professionals in the interior design industry, including architects, engineers, acousticians, and a sociologist. He worked with an organist, Jean-Luc Guionnet, which led him to draw a connection between the organ’s pipes and the air conduits in buildings. “I sincerely believe that every ventilation system becomes, or is, a wind instrument,” he tells me. “A continuous breathing system. As with an instrument, what happens in an air network is linked to the complexity of its architecture.”
The curves and twists in a building’s air ducts are analogous to the turns and valves in a musical instrument. This is why the vents he recorded all sound different. And much of the differences and sound have to do with imperfections in the system, which can occur for many reasons.
La Casa explains that, when buildings are being designed, the ventilation ducts need to be planned via sets of complex calculations. If those calculations are off, you’ll get turbulence — which produces noise.
Then there’s wear and tear. These networks of ducts must be kept in good, clean order. “A system that plays with forced air always ends up producing unforeseen effects if you didn’t have any maintenance,” he warns.
And lastly, there is basic user error. Since few people know why ventilation systems exist, many will unwittingly disrupt the system’s flow, for example by putting furniture in front of a vent. This one indiscretion can throw off the entire building’s ventilation network as a whole, causing turbulence and noise.
La Casa explains that mechanical ventilation was developed by engineers to solve a technical problem — circulating air in rooms that don’t have direct access to the outdoors via windows. But those engineers didn’t consider how users were adopt their system; those answers, instead, would have lain within the fields of anthropology and sociology. For example, cultural beliefs about the purpose of ventilation — and its adverse effects — have emerged over time. “Depending on the period, theories have spread in our societies to make mechanical ventilation responsible for benefits (filtration of fine particles …) or, on the contrary, for problems (mainly on health, instead of sound).”
La Casa explains that engineers are keen to develop technical solutions to human problems. And, La Casa points out, “mechanical ventilation technically meets new interior standards for human habitation while preserving the building.” As a consequence, it has been implemented universally.
“Living in southern Italy and northern Scandinavia is not at all the same. But in the end, it becomes the same in terms of normalizing indoor comfort. Architects seized on the fact that one can use the mechanization of the air in a building to expand their vocabulary. Thus, the interior space today is more and more equipped and governed by increasingly sophisticated techniques to guarantee and meet the standards of comfort of human life.”
The architects and engineers who design air conduits do take their sonic properties into account, but in a highly technical way. “Each object is defined by its sound level, which now meets strict specifications and noise standards. I went to a building measurement center to understand how these exhaust air measurements were made. In an empty building of typical dimensions, measurement microphones record the sound level. Here, no one cares whether the permanence of this noise in a space is desirable, or whether the user really wants it. The technical obviousness of a mechanical air system is something everyone now has to accept. In fact, the issue of noise is completely peripheral, even secondary. Engineers are more concerned with the flow of air in space. They don’t like people asking about noise.
“For AIR.ratio I put them face-to-face with this question while inviting them to be creative in their way of arranging their systems: why not call on musicians from the design stage to get out of the strictly technical culture and try to instead deal with the ‘musical’ question beyond noise? Let’s get out of this noise culture to see that we live in a complex sound world that could also have hidden musical goals.”
La Casa, who has produced an extensive discography, still looks back on AIR.ratio fondly. “I find that what ventilation tells us — about contemporary architecture, our relationship to the exterior, our need for control, our society, its relationship also to noise, and to the continuous, therefore to time, etc. — is particularly rich in teaching and expressiveness, and therefore artistic potential. I could continue to work on ventilation to this day. But because I don’t want to become an expert on this at all, I’m not sure I should. It seems to me that AIR.ratio allows us to enter into this topic of ventilation through our listening – which is quite an original way to address this question.”
Since creating AIR.ratio, La Casa hasn’t stopped thinking about ventilation systems. “Ventilation is at the center of our new strategy of living indoors, bringing to us the vital elements of our survival: water, air, electricity, and now food… This is the gradual establishment of an internalization of our society. The inside has now taken on more importance in our lives than the outside. Everything seems to indicate that we are spending more and more time indoors, and that goes through the elevation of indoor comfort. Ventilation is clearly one of the essential components of this strategy. Air is now an important building issue.
“To sum up: we have moved from the fields to the offices, and for that we had to increase the comfort of life and accentuate our technical and even technological efforts. And this is a process that accelerated at the end of the 20th century. It is a constant thought of engineers, and an increasingly growing demand from residents, to meet the new challenges facing the city.”