Sound is detected and processed by the auditory system, which includes the ears, the auditory nerves, and the brain. When sound enters the ear, the eardrum vibrates, and this vibration is transmitted to the bones in the middle ear (the malleus, incus, and stapes), and it goes to the cochlea, a spiral-shaped structure deep in the inner ear. Inside the cochlea, the vibrations are converted into mechanical signals that pass to the brain via the auditory nerve, the brain processes these signals and interprets them as sound.
Hearing, like vision is a sense that operates well at distance. Although it is slower and weaker than light in sending information through air, sound travels through the medium to get to the ear. Sound also travels very well through other liquids and solids, because it moves through the vibration of matter, and liquids and solids have higher densities than air and other gasses, which allows a more efficient transfer of the wave energy. As such, we can hear sound through materials, not just through air. In fact, sound is more efficient through dense materials, and we must be careful not to injure our ears with over-powerful transmissions, such as pinging in water.
We use hearing to intake information and sounds in order to better understand the world. Often, we use it in combination with other senses, or we can use it alone, in lieu of vision and others. Sound provides meaning without a need for light. Not only do we receive sounds from specific sources, but we also take in the sound of the context and conditions. Reverberation tells us the make up and size of spaces, while the milieu of sounds expresses environmental conditions.
Similar to vision, hearing is always on when awake. Although hearing can be passive, hearing incidental sounds, hearing is almost entirely active. However, we are able to block out sound with our brains and can even sleep through commotion, and our brain is able to filter out the sense to focus on other signals or tasks.
We use hearing wherever we use vision. However, we can also utilize hearing without sight, and it is nearly as efficient as relying on the visual, though full physical definition is more difficult to discern. When used in concert with vision, a very clear understanding is given, only made better by touch, in most instances.
For some, hearing and listening are the greatest skills. Some get lost in music or the sonic landscape, and they can pick out specific characteristics and sounds without trouble. For these people, hearing is very important. For others, they might use hearing as a secondary mode to understand the world, which is also very effective in concert with other senses, such as touch and vision.
We are able to affect how people hear by masking or blocking sound, enhancing sound, or combining sound to create new possibilities. These options give new experiential moments. As mentioned above, we are able to use our sense of hearing to understand the size and contents of a space as well as define what entities are nearby, but our ability to listen also allows us to receive spoken language, like written language for vision.
Manipulating sound electronically or using acoustical mechanisms, we can change how people hear and also what they hear. However, we are also able to adjust sonic experience by manipulating our ears and hearing. People who wear headphones or hearing aids are able to filter out the environment and only experience portions of the world of sound. These devices are able to adjust pitch and amplitude, meaning anyone wearing one will have a different experience than one without. The sonic landscape can also be changed with various effects such as reverberation and delay. These two can change the nature of a space, because they can augment or diminish the experiential size of the space just with adjusting the qualities of the sound.
We transform the signal in our minds through associating the sound with some value or memory. These associations come naturally from our existence in the environment or the repetitive introduction of the signal over time. As mentioned above, removing sound affects the listener, but we can also use additive design to create new sonic experiences. Our brain can understand a new meaning from overlaying multiple sounds. In fact, this is the way movie makers create new sounds for their films.
These sounds can be considered good, bad, or neutral, but we can also place a meaning on it by associating values. Producing the sound multiple times in connection with another object or entity, we are able to create new connotations. We can also affect the memory of a sound be repetition of the sound during experience of some event or input from another sense.
Hearing is used nearly constantly throughout the day, and sound enhances other senses and emotions. The content of a movie is affected tremendously by sound, and the quality of these sounds can improve or lower the quality of the film’s perception. Most people will preference the visual when traversing the environment, but sound is a great indicator, and many things in our world signal or can be sensed through sound. The sense works at a distance, but there is a disparity in the speed of the signal of sound and of light, and the two quickly separate over distance creating silent visual events and later disembodied sounds that may match or differ greatly with the perceived image. Nevertheless, sound is extremely useful in our day to day lives and throughout history, as we accept language first aurally and second visually. Language is believed to come from sounds from individuals long before the written word. As such, it may be intrinsic and atavistic to our working brains.
We use hearing to create memory and understanding in our lives, as well as to apply, analyze, and evaluate the world in order to create and thrive. It is crucial that we create these memories of sound in order to provide a description of the object and use this understanding to create meaning that acts as a catalyst or stimulus to put us into action. With this, we can think about how the thing emanating sound works or acts and later judge how it can be used or avoided. Finally, with the mastery of the sound and hearing in general, we can create new sonic signals to interact with the environment.
Hearing may not be our first or primary sense, but it is extremely useful to navigate the world. In some situations, it may be our only sense that allows us to be safe and interact with the environment. Because it is such an intrinsic and important sense, we draw associations through specific sounds, and these may be shared from culture to culture or may be very different. However, the quality and form of the sound provides information that can be shared across populations and languages. In some instances, it is possible and maybe even important to impart meaning on something, such as an alarm or the buzzing of a hornet, in order to exist safely.
The sense of hearing is extremely useful, but it can overpower the user and muddle meaning when combined with other sensory input. As with other senses, it is best to start with no or minimal sound and build up. One of the beautiful things about sound is that it can describe three-dimensional space and directionality. So, multiple outputs or speakers are suggested when working with sound design. These outputs can be linked like Dolby Surround Sound, or the sounds can be from multiple independent sources to create a mélange. Even with the multiple sounds, each should start at a low volume and augmented to the desired amplitude, however the sound volume can vary from source to source and could even change over time.
Some music producers talk about making space in compositions. This is the use of silence to enhance the music. Even the best sonic signal can be monotonous or overpowering when played too long, so rests or pauses in what is heard is very helpful to create structure and understanding, while the variation provides interest. Even a single sound or voice should be separated with pauses to create an aural rhythm that will satisfy the user. Sometimes what is not heard is as important as that which is heard.
If we only designed with hearing, we would have a rich spatial environment, but the limited sensory input would require one or very few inputs if trying to convey information. So, sound requires a hierarchy and maybe even a mode of interaction. If a design requires call and response, the user must understand when and how to interject into the system. If a design has one source producing or controlling the sound, then how will the user be able to interact with others and with the source? This system should easily allow the listener to interact or at least react to the source of the sound.
If design did not include hearing, how easily can individuals interact? Every environment has sound, and it is nearly impossible not to hear or create sound when moving through a space. The absence of sound would ensure the other senses are front and center. But, the order or hierarchy of a design might not be apparent without sound, though it is much more likely that the absence of vision would make an impediment of a structure.
Some alternative senses for hearing would be sight, but also smell and touch. All of these can provide multi-dimensional experiences, especially when they are used in combination. Oppositely, if we want to create a personal experience with sound, it is possible to limit the dimensionality of the sound by experiencing the sense through a liquid or solid medium. The vibration of the sound waves requires mass to allow the noise to propagate, and liquid and solid materials are very good and efficient means to broadcast. However, the listener must be in contact with the medium, in order to hear the sound, and the source of the sound seems to come from the body part that is touching the medium. This creates a very close and intimate experience.
An environment can be augmented with sound, but we must keep in mind the method. Locating places and objects from which sound will emanate is good, but we must tastefully develop the sonic environment with low volume, building these up, then adjusting the frequency of the sound to better engage with the space. Each space has a specific frequency and resonance, as well as other acoustical properties, and the designer can use these to grab the listener’s attention. When the specific frequency is hit, a space seems to buzz and come to life, tottering and rumbling. When the designer uses the existing space’s acoustical properties, the designer creates a stronger bond between the new design elements and the existing environment. A tall space with hard surfaces will give a very active sonic landscape, with echoing, reverberation, and delay. A small, padded space will feel internal and quiet.
Design is a reiterative act, and the architect would want to evaluate the sound work developed in order to improve or build upon the soundscape. Because this is likely a qualitative evaluation, the designer should determine if one sound state is better, the same, or worse than another. If the state is better, then it is likely the architect will want to keep it, but if it is worse, then what should be done? A new sound or audio source should be tried, tested, and evaluated, and then another, if necessary. If a state continues to be worse than the original or the highest use, then it may very well be likely that the environment does not need sound.