Enter the underground shelters of Penn Station in New York and you may just feel a restless sense of claustrophobia, which is difficult to explain. Take a walk on the wooden floor at the National Gallery of Art in Washington, DC, and a sense of calm can come down on you. Why? Each of these buildings has its own unique voice – the way the sound is kept within the structure.
Think of the way the whispers travel in the circular dome of St. Paul's Cathedral in London and how the curved ceiling of New York's Grand Central in New York can carry voices. Then there is the satisfying clicking of heels going through an empty hallway or the way your bathroom makes your singing sound better. This "sound architecture" can have a profound effect on the way you experience a building. (Read how you can get around the room with just a click)
"Archival architecture is about how we listen to buildings, the sound in buildings and how we respond to them," says Trevor Cox, an acoustic engineer at Salford, Manchester. Although we mainly navigate the world using our eyes, it seems that our ears are constantly gathering information from our environment, which unknowingly changes the way we feel about a space.
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although they do not emit sound, you can hear an empty room. You can find out if it has low ceilings and where its walls are exactly the way the sound is reflected from these surfaces. Consider the echo of noise that the clicking of the heel makes on the marble floor as opposed to the muted pad from someone walking on a thick carpet.
"You can go into a blindfolded room and you can probably hear if there is a carpet on the floor without stepping on it," says Barry Bleser, a former electrical engineer at MIT who coined the term aural architecture. "We can hear all kinds of things. We just don't pay attention. "
We were probably all in a building that sounded wrong. Fearful offices where noise rattles awkwardly between floor and ceiling, old houses where the squeaks and moans of aging floorboards are carried ghostly from room to room, railway stations where public communications are reflected until they are incomprehensible.
There is growing recognition that buildings must not only be functional and aesthetically pleasing but also acoustically satisfying
Although it may be difficult to put your finger on why, these places may feel instinctively uncomfortable for us.
Now, there is increasing recognition that buildings must not only be designed to be functional and aesthetically pleasing, but also acoustically satisfying ̵
Scientific research suggests that it is reasonable to do this, Noisy work and home conditions have been proven to annoy people, and noise irritation itself is associated with depression and anxiety. In addition, problems with workplace concentration due to office and intermittent noise have been found to significantly reduce human performance.
But the way sound interacts with the physical structure of a building can also significantly alter our moods and emotions. For example, studies show that living in overcrowded housing can create a sense of helplessness. Rooms with higher ceilings encourage more abstract thought as people feel more free in such spacious spaces. Think of the emotional impact of a structure such as Saint Sofia, the famous former cathedral and mosque in Istanbul, which now houses a museum. Built nearly 1500 years ago, its domed interior and marble floors and walls can elicit human chants in ethereal sounds that seem to radiate from the depths of the ocean and create a sense of elevation in the listener.
"He has a sound aesthetics that is capable of awakening the divine," said Bissera Pencheva, an expert on medieval art at Stanford University who studies the spiritual aspects of medieval structures. "It takes human speech and chanting outside the human language register."
Mainstream architecture typically considers the sound of the building's voice only when constructing concert halls where acoustic perfection is key. The idea that you can take this one step further and build a building acts as a kind of musical instrument that surrounds people capable of provoking a feeling of calm, excitement, tension or even a trance-like state. However, it is not known.
The way sound interacts with the physical structure of a building can also significantly alter our moods and emotions
When a person's voice hits a frequency of 110Hz in the "Oracle room" at the 5,000-year-old Maltese underground temple Ħal Saflieni Hypogeum, comes to life. As more voices join in, sounds amplify from every direction until it can literally feel like tingling through the skin. A neurological study examining how the acoustic properties of ancient structures affect brain function finds that briefly listening to a 110Hz tone reduces activity in the brain's language centers and redirects activity to emotional areas of the brain.
If the acoustics of space are tuned to amplify only one tone, it can affect us so deeply, what effect can a room have that amplifies many on our consciousness? Shea Michael Trahan, architect at Trapolin-Peer, uses brushes – the way surfaces vibrate – and 3D printing technology to answer this question. He creates 3D structures that he hopes could be enlarged so you can go in and sing a B plane or a C major to make the building resonate or "sing" back.
"What you are aiming for is to create spaces that isolate a tone, like Matimandir, a golden geodesic dome used as a space for meditation, focuses a single ray of light," says Trahan. "Hyper-resonance is actually the gift of architects to the observer, as it uses their sound and extends it as much as possible to enhance or enhance the experience."
It is likely that it can use beyond the creation of spaces, in which is a pleasure to spend time with. These sound-interactive structures could function as immersive sound therapy rooms for existing sound therapies for PTSD, depression and Parkinson's disease. Vocalists could even use them to tune their voice to hit the tones with precision. ( Read how hospital noise can impair patient safety )
"When space acts as a tool, space can set you up," says Trahan.
Susan Magsamen, Executive Director of International Arts and Mind Lab at Jones Hopkins University in Baltimore, is involved in a multidisciplinary project that aims to create a whole new type of healing space for children who are woken up by traumatic brain injuries. Scheduled to be built later this year, Kennedy Krieger Children's Hospital Sensory Care will personalize sounds, such as a mother's voice or song, favorite scents, temperature and light of an individual child, in a room that feels like a cocoon. help kids wake up faster and better.
Michael Fowler, a member of the audio communication group at the Technical University of Berlin, approaches audio architecture differently. It is inspired by open spaces that have unique sound features, such as Japanese gardens that feature dry stone waterfalls that flow like real waterfalls, from the skillful positioning of water features out of sight. He studies what he calls "exemplary" sound spaces, in an effort to understand what makes them special, be it geometric shapes or the arrangement of materials in one room. He wants to use this to create an algorithm or computational routine, something like a digital auditory archetype that architects can use when designing buildings or other public spaces.
"Using this, you can create this type of sample space, and they can exist in many different media, but their actual structure, the relationship between sound and space, will be common to all of them," Fowler says. "Although, when you abstract them, they may look completely different."
However, the buildings do not exist in isolation. They form cities and towns where traffic roars, construction booms, stormy nightclubs and piercing howls of sirens and alarms will not escape. About 83 million people in Europe live in areas where sound pressure levels are above recommended levels, Fowler says.
New technologies and new types of materials can help. Extending existing structures with vibrating facades, for example, could potentially eliminate noise by using interference physics. Create a sound wave with the right frequency and wavelength and it will counteract the sound waves of unwanted noise.
"In the future, it is possible that if you live near an airport, as soon as you step within a few meters of a building, the sound from the airport will disappear due to the active noise suppression throughout the building," Fowler says.
if it's not possible to get rid of the noise, why not embrace it? Make a musical noise, for example. In 2016, Jordan Lacey, a research associate at RMIT University in Melbourne, created a noise transformation facility that picks up noise from neighborhood traffic with the park through microphones, mixing it with music sounds and into them produced through loudspeakers in the park area, inhabited by people living in close quarters who want to sit on their balconies instead of shutting down outside.
envisions the MIX concept house designed by Karen Van Lengen, an architect at the University of Virginia and her colleagues recessed windows that act as "sound dishes" that can be angled in different directions to capture sounds from the surrounding neighborhood. Homeowners can then mix these sounds through an audio system to create musical compositions in which a dog barks or a yelling child becomes an ambient soundtrack.
We have not evolved by listening to the hum of the air conditioners or the creaking tires
it is one thing to invite the noises of our surroundings into our homes in new ways, is it possible to avoid them completely? Architects charged with designing future cities are now more aware of the need for quiet and natural sounds in urban sound maps. After all, we didn't develop to listen to the noise of air conditioners or the rustling tires. Lacey believes it is important to have sound architecture installations in cities to create a network of "sound breaks" – places where existing urban noise is transformed by technology and landscaping to create unique sound maps which are aimed at enriching the experience of people in a given field.
"It's all very well to complain about the noise of the city and say that it must look more like nature, but what about all the people who don't have access to it," says Lacey. "We can design these sound environments to give people not the experience of nature, because it is not nature, but some urban equivalent. Consider how big some of these cities will be in 50 years. "
Thanks to virtual reality systems, architects begin to hear how the spaces they design can sound through" rumors "of structures using acoustic modeling software like Odeon. Such rumors are used to prevent the transmission of sound between spaces and to design decisions, such as where to place absorbent, diffusive or reflective surfaces.
"Architects are able to hear what their designs look like and, when necessary, adapt them to improve their acoustic performance," says Naomi Tancy, an acoustics consultant at the engineering firm Arup. creating unique spaces, such as the central hall at the Hamburg Elbphilharmonie, which has a stunning "skin" algorithm made of 10,000 gypsum fiber acoustic panels that help create a balanced sound.  Others such as JU "Marianna Lopez is studying acoustic heritage through software." Auralisations are used to allow us to listen to spaces that either no longer exist or have changed throughout history, "says Lopez. In addition to preserving acoustic history, these rumors important for the restoration of historic structures, since the materials used can significantly affect the acoustics.
But it may still take some time before our homes, offices and cities become as pleasant to the ear as they
on bureaucracy or politics doesn't say we have to design it, "Lacey says. "We design to a minimum."
If we can start to see sounds like Fowler treating them as clay-like material, something that needs to be shaped, shaped and composed, that can open up really exciting possibilities in a way to design our acoustic environment. "If you knew the sounds, how it related to space, and how to change its behavior," Fowler says, this could expand our experience of the built environment around us.
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