Entering the underground corridors of New York's Penn Station may cause you to experience an uncomfortable feeling of claustrophobia that is difficult to explain. If you stroll across the parquet floors at the National Gallery of Art, Washington DC, you may feel a sense of calm. Why? Each of these buildings has its own voice – the way the sound behaves in the structure.
Remember the whisper in the round dome of St. Paul's Cathedral in London and the curving ceiling in the basement of Grand Central London's New York can carry voices. Then there's the satisfying click of the heels that go through an abandoned corridor, or the way your bathroom sounds better to your singing. This "acoustic architecture" can have a profound effect on the way you experience a building. (Read how to navigate a room with just one click.)
"Acoustic architecture is about how we listen to buildings, how they feel and how we react to them "Says Trevor Cox Acoustician at the University of Salford in Manchester. Even as we move through the world with our eyes first and foremost, our ears seem to be constantly picking up information from our environment that unconsciously changes our attitudes to a space.
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• Could wood buildings be a solution to climate change? Sound, you can hear an empty room. You can find out if it has low ceilings and where the walls are, just as the sound is reflected off these surfaces. Think of the echo that creates the click of a heel on a marble floor, as opposed to the cushioned upholstery of someone walking on a thick carpet.
"You can go blindfolded into a room and you can probably hear if there is a carpet on the floor floor without stepping on it," says Barry Blesser, a former electrical engineer at the Massachusetts Institute of Technology, who used the term has shaped the acoustic architecture. "We can hear all sorts of things. We just do not watch. "
We were all probably in a building that sounded wrong, grubby offices where noise rattles unpleasantly between floor and ceiling, old houses where stations hear the creaking and groaning of aging floorboards public announcements echo until they are undetectable.
Buildings are increasingly recognized It not only has to be functional and aesthetic, but also acoustically satisfying.
Even though it may be difficult to keep a finger on the Why place them, these places can instinctively feel uncomfortable for us.
Now there is a growing recognition for buildings It must be not only functional and aesthetic, but also acoustically satisfactory.Some architects and engineers have to rethink how spaces are shaped and what materials they consist of.
Scientific research suggests that this makes sense Work and home environments have been proven to disturb people, and noise itself has been linked to depression and anxiety. In addition, problems related to office noise and temporary workplace noise have been found to significantly affect human performance.
However, the way sound interacts with the physical structure of a building can also significantly change our moods and emotions. For example, studies show that living in overcrowded homes can create a sense of helplessness. Rooms with higher ceilings encourage more abstract thinking, as people feel freer in such airy spaces. Consider the emotional impact of a structure like Hagia Sophia, Istanbul's famous former cathedral and mosque, which today houses a museum. The vaulted interior and marble floors and walls, built almost 1
"It has a sonic aesthetic that can conjure up the divine," says Bissera Pentcheva, an expert on medieval art at Stanford University who studies the spiritual aspects of medieval structures. "It takes human language and song that transcend the register of human language."
The mainstream architecture usually considers the sound of a building only in the construction of concert halls where acoustic perfection is the key. It is unusual for you to take this step further and let a building itself act as a kind of musical instrument that surrounds people and is able to evoke a sense of calm, amusement, tension, or even a trance-like state. It is not unknown, however.
The way sound interacts with the physical structure of a building can also significantly change our moods and emotions.
When a person's voice reaches a frequency of 110 Hz in the Oracle Room of the 5,000 series. The one-year Maltese underground temple Ħal Saflieni Hypogeum comes to life. It is as if more voices are joining, and the sounds amplify from every direction until they are literally perceived as tingling in the skin. A neurological study that examined how the acoustic properties of old structures affected brain function revealed that the brief hearing of a 110 Hz tone reduced activity in the brain's language centers and shifted activity to the emotional areas of the brain.
amplify only a single tone can affect us so profoundly, what influence could a room, which amplifies many, have on our consciousness? Shea Michael Trahan, architect at Trapolin-Peer, uses Cymatics – the way surfaces vibrate – and the three-dimensional printing technology to answer that question. He creates 3D structures that he hopes can be magnified so that you can go in and sing B or C major to resonate the building, or "sing back".
"What I'm Looking For It's about creating spaces that isolate a single sound, much like the Matrimandir, a golden geodesic dome that serves as a meditation space and focuses a single beam of light," says Trahan. "Hyper-reverberation is actually the gift of architecture to the viewer, using their sound and extending it as much as possible to enhance or amplify the experience."
There is a possibility that this will be beneficial beyond the creation of spaces where time is worthwhile to linger. These acoustically interactive structures could act as immersive sound therapy rooms for existing sound therapies in PTSD, depression and Parkinson's. Singers could even use them to tune their voices to make precise sounds. Read How Hospital Noise Can Endanger Patient Safety .
"When space acts as an instrument, space can make you agree," says Trahan.
Susan Magsamen, General Manager of International Arts and Mind Labs at Johns Hopkins University in Baltimore are participating in a multidisciplinary project aimed at creating a whole new healing space for children recovering from traumatic brain injury. "The Sensory Care Room" at the Kennedy Warrior Children's Hospital is said to be still in this Year built and in a room that feels like a cocoon, tune sounds like a mother's voice or song, favorite smells, temperature and light to the individual child so that children wake up faster and better.
Michael Fowler, Member The group for audio communication at the Technical University of Berlin deals with acoustic architecture differently. He is inspired by open spaces with unique sound features, such as Japanese gardens with dry stone waterfalls that ring like real waterfalls, and the skillful positioning of water features that can not be seen. He explores what he calls "exemplary" soundscapes to find out what distinguishes them, be it geometric shapes or the arrangement of materials in a room. He wants to use it to create an algorithm or calculation routine, a kind of digital acoustic archetype that architects can use when designing buildings or other public spaces.
They may exist in very different media, but their actual structure, the relationship between sound and space, will be common to all, "says Fowler. "If you abstract them, they might look completely different."
However, buildings do not exist in isolation. They are cities in which the noise of traffic, the boom of construction, booming nightclubs and the pervading howl of sirens and alarms are unmistakable. Around 83 million people in Europe live in areas where sound pressure levels are above recommended levels, says Fowler.
New technologies and new types of materials could help. For example, expanding existing structures with vibrating facades could potentially compensate for noise by exploiting the physics of interference. Produce a sound wave with the right frequency and wavelength to counter the sound waves of unwanted noise.
"In the future, it is possible that you live near an airport, as soon as you enter a couple meters near the building the noise of the airport disappears due to the active noise cancellation of the entire building," says Fowler.
But if it is not possible to get rid of the noise, why not accept it? For example, make traffic noise musically. Jordan Lacey, a research associate at RMIT University in Melbourne, created a noise transformation installation in 2016, which recorded the traffic noise near a park via microphones, mixed with musical sounds and played speakers in the parking area. Here people lived in nearby residential areas that wanted to sit on their balconies rather than foreclose from the outside.
The Conceptual MIX House, designed by Karen Van Lengen, an architect at the University of Virginia, and her colleagues, looks at concave windows that act as "sonic shells" and can be tilted in different directions to make noises to capture from the environment. Homeowners can then mix these sounds through an audio system to create musical compositions that turn a dog bark or crying child into an ambient soundtrack.
We have not developed the humming of air conditioners or squealing tires
It is a matter of inviting the sounds of our environment into our homes in a new way. is it possible to escape them altogether? Architects commissioned to design future cities are more aware of the need for soft and natural sounds in urban soundscapes. After all, we did not hear the hum of air conditioning or squealing tires. Lacey believes it is important to install sound architectural installations in cities to create a network of "sonic breaks" – places where existing city noises are transformed using technology and landscaping to create unique soundscapes that enhance the experience of the To enrich people in an area.
"It's good to complain about the city noise and say it has to be more like nature, but what about all the people who do not have access to it?" Lacey says. "We can design these acoustic environments so that people do not experience nature because it is not a matter of nature, but a kind of urban equivalent. Think about how big some of these cities will be in 50 years. "
Using virtual reality systems, architects are beginning to hear how their designed spaces could sound through" auralization "of structures using acoustic modeling software like Odeon. Such auralizations prevent sound transmission between rooms and make design decisions where to place absorption, diffusion or reflective surfaces.
"Architects can hear what their designs sound like and adjust them to improve their acoustic behavior," says Naomi Tansey, Acoustic Advisor at Arup Engineering Office Hamburg's Elbphilharmonie, which uses a stunning algorithmically engineered "skin" made of 10,000 gypsum fiber acoustic panels that contribute to balanced reverberation.
] Others, such as Mariana Lopez of the University of York, use software to study acoustic heritage. " Auralizations allow us to intercept spaces that either no longer exist or that have changed throughout history. "In addition to preserving the history of acoustics, these auralizations are important in the restoration of historical structures, as the materials used significantly enhance the acoustics can influence.  However, it may take some time for our homes, offices and towns to become as comfortable to the ear as they are to the eye.
"Nothing in the language of bureaucracy or politics says we need to design for it," says Lacey. "We design to the minimum scale."
If we could begin to see sounds like Fowler, seeing them as a clay-like material that needs to be sculpted, sculpted, and composed, it could open up truly exciting possibilities to construct our acoustic environments , "If you are familiar with sounds, how they relate to space, and how to change their behavior," says Fowler, this could extend our experience of the built environment around us.
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