5.6 Categories of Sound

In certain product categories such as vehicles, electronics, and many domestic products, users perceive auditory cues to be as important as visual ones (Knöferle, 2012; Schifferstein, 2006). A product’s sounds transfer information about its functioning, which can be categorized into two different kinds of sound categories, based on the sound’s source of origin – consequential or intentional.

1. Consequential sounds result from the internal or external structure of a product, especially products with moving parts. Sounds are emitted by the product in relation to how they function, such as a lawnmower or washing machine. These products contain multiple sound-producing parts like running engines, rotating gears, fans, bouncing springs, pumping water, or blowing air. These mechanical sounds inform us about the product functioning cycles and listeners cannot intervene to change the sounds while they occur (Özcan & van Egmond, 2008; Langeveld et al, 2013).

2. Intentional sounds are the second kind of sounds – often used in product interfaces and controls. These are added, designed, implemented, and put into a product by a sound designer, like cell phone alerts, microwave oven finish bells, and oven setting feedback sounds. They are mostly digital and abstract, but listeners learn to attribute meaning to them since they convey messages. Listeners may feel obligated to attend to the message being communicated (Özcan & van Egmond, 2008; Langeveld et al, 2013). Perhaps that is why we almost always respond to our beeping phones, even when we are in the middle of other activities.

Sounds can be the consequence of moving structural parts or intentionally designed

Semantic Descriptions of Sounds

Sounds are often expressed in descriptive terms because scientific terms are not widely known. In addition, the way we perceive the character of a sound can depend on both perceptual and cognitive factors (Özcan & van Egmond, 2005) and, as a result, sounds described in the categories below vary in their spectral-temporal composition, the material interactions that cause the sound and their conceptual associations. Through their research into how participants describe sound types, Özcan and van Egmond (2005) organized sounds into the following six perceptually distinguishable groups using semantic associations:

1. Air sounds were generally defined by location (where the sound takes place), action (the action causing the sound), and psycho-acoustical (physical properties of sound like pitch and tone). Examples of air sounds included vacuum cleaners, hair dryers, and vacuuming motors.

2. Alarm sounds were described through abstract meanings, source descriptions, and onomatopoeias. Examples of alarm sounds included bells, microwave button feedback, warnings, alarms, and other attention-getting sounds.

3. Cyclic sounds, which resembled air sounds,  were identified by source, location, psycho-acoustical properties, and action descriptions. Examples of cyclic sounds included dryers, fans, monotones, and ventilator backgrounds.

4. Liquid sounds were described by action, sound source (the medium in which the sound was produced) and onomatopoeias. Examples of liquid sounds included coffee machines, boiling, pouring, and filling.

5. Impact sounds were described by temporal aspects (duration and constancy of sound), source properties, onomatopoeias (imitations of sounds), and materials (used in the product). Examples of impact sounds included doors, switches, banging, and opening.

6. Mechanical sounds were described by sources, action descriptions, emotional responses (how people feel in response to the sounds), onomatopoeias, and abstract meanings. Examples of mechanical sounds include shavers, rattling, buzzers, electro-motor, mechanical and high-pitched noises.

Sound descriptions Categories

Consequential & Intentional Sounds