Hearing
Overview | Understanding hearing | Hearing functions (4) | Env. context | Design guidance | Pop. stats. (2)
Hearing functions
Introduction | Sound detection | Speech discrimination | Sound localisation
Human ability to discriminate speech is an important consideration when designing products that facilitate verbal communication or use speech output.
Examples include telephones, cash machines, car navigation systems, and accessible technology that aids people with low vision through alternative speech output.
Speech sounds can be detected when they are of sufficient loudness, but discrimination of speech can be difficult for some people, especially in the presence of noise.
Male or female voices can be used for speech. Generally male voices are of lower pitch and are within the range of hearing. Various accents and intonation can also affect how well speech is understood.
Speech output can be prerecorded and replayed or speech can be synthesised. Synthesised speech is more difficult for older people to understand.
Speech can become difficult to understand if it is recorded, played back or synthesised at high speed.
Following a conversation is more difficult in a noisy environment, especially for those with reduced ability to discriminate speech
Products with speech output can be difficult to understand if the ambient noise levels are loud
Overview | Understanding hearing | Hearing functions (4) | Env. context | Design guidance | Pop. stats. (2)