Definition
- Hearing is the perception of sound produced when sound waves are transduced by the organ of Corti in the cochlea into action potentials in the auditory nerve.
- Audible range is 20 to 20,000 Hz; hearing threshold is 0 dB at 1000 Hz.
Properties of Sound
Normal values in hearing
Parameter
Speed of sound in air
- Normal value
- 340 m/s at 20°C, sea level
Speed of sound in water (fresh)
- Normal value
- 1400 m/s
Audible frequency range
- Normal value
- 20 to 20,000 Hz
Best frequency sensitivity
- Normal value
- 1000 to 4000 Hz
Best pitch discrimination
- Normal value
- 1000 to 3000 Hz (Δf as small as 3 Hz)
Hearing threshold
- Normal value
- 0 dB at 1000 Hz
Pain and ear damage
- Normal value
- 140 dB