Loudness

Definition

Loudness is the perceptual response to the intensity of a sound wave, often measured in decibels (dB). It reflects the human ear's sensitivity to different frequencies and amplitudes.

5 Must Know Facts For Your Next Test

1. Loudness is subjective and depends on both the amplitude of the sound wave and the frequency.
2. The unit of loudness is typically measured in decibels (dB), which is a logarithmic scale.
3. Human hearing ranges from about 0 dB (threshold of hearing) to around 120 dB (threshold of pain).
4. Doubling the intensity of a sound does not double its perceived loudness; it increases by about 3 dB.
5. The Fletcher-Munson curves illustrate how loudness perception varies with frequency.

Review Questions

• What unit is used to measure loudness?
• How does doubling the intensity of a sound affect its perceived loudness?
• What are the Fletcher-Munson curves used to illustrate?

Related terms

Decibel: A unit used to measure the intensity of a sound, representing a logarithmic scale relative to a reference level.

Sound Intensity: The power per unit area carried by a sound wave, usually measured in watts per square meter ($W/m^2$).

Frequency: \(\text{The number of oscillations or cycles per second of a sound wave, measured in Hertz (Hz).}\)