Beating refers to which phenomenon?

Beating refers to which phenomenon?

• A. Fluctuation caused by two close frequencies
• B. Separation of tones by the critical band
• C. The suppression of loud sounds
• D. The reflection of sound

Answer: (A)

Beating occurs when two tones with very similar frequencies are played together. Their waves interfere, so the resultant signal grows and diminishes in amplitude over time. This amplitude modulation—the beat—happens at a rate equal to the absolute difference between the two frequencies (for example, 440 Hz and 442 Hz create a 2 Hz beat). You hear a pulsing or throbbing rather than a single new pitch, which distinguishes beating from other phenomena. The other options describe different auditory effects: spectral separation by the critical band relates to how tones are heard within the ear’s frequency resolution, suppression of loud sounds refers to masking or loudness interactions, and reflection of sound is an echo.

Beating occurs when two tones with very similar frequencies are played together. Their waves interfere, so the resultant signal grows and diminishes in amplitude over time. This amplitude modulation—the beat—happens at a rate equal to the absolute difference between the two frequencies (for example, 440 Hz and 442 Hz create a 2 Hz beat). You hear a pulsing or throbbing rather than a single new pitch, which distinguishes beating from other phenomena. The other options describe different auditory effects: spectral separation by the critical band relates to how tones are heard within the ear’s frequency resolution, suppression of loud sounds refers to masking or loudness interactions, and reflection of sound is an echo.