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 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 would 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, however it is much more likely that the absence of vision would disallow 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, as well as 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 of the new design elements and the existing environment. A tall space with hard surfaces will a very active sonic landscape, with echoing, reverberation, and delay. A small, padded space will feel internal and quiet.
Design is a reiterative profession, 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.