Shrill and deep

The idea

Pitch is how humans perceive frequency: shrill sounds have high pitch and deep sounds low pitch, and in general higher pitch means higher frequency, though the exact relation is complicated.

A whistle and thunder

A whistle gives a shrill sound. Thunder gives a deep rumble.

How do you think the frequencies of a shrill sound and a deep sound compare?

• The shrill sound usually has the higher frequency
• The deep sound usually has the higher frequency
• They have the same frequency

Raise the frequency

Slide the frequency. The numbers are only a picture, not real values.

How we hear frequency

Pitch is how we perceive frequency. A shrill sound has a high pitch and a deep sound has a low pitch. In general a higher pitch goes with a higher frequency, although the exact relation is complicated.

Pitch is how humans perceive frequency. Shrill sounds, like a whistle or a siren, have high pitch. Deep sounds, like thunder or an aircraft rumble, have low pitch. In general, higher pitch means higher frequency, though the exact relation is complicated.

Notes

Pitch is how we perceive frequency: shrill is high pitch and deep is low pitch. In general, higher pitch means higher frequency.

Check yourself

What is pitch?

Which of these sounds has a high pitch?

A sound has a low pitch. In general, what can you say about its frequency?

Which description fits a whistle?

• How humans perceive the frequency of a sound — correct. Yes!
• How humans perceive the amplitude of a sound. That is loudness. Pitch is how we perceive frequency.
• The distance between two crests of the sound wave. That is the wavelength. Pitch is how we perceive frequency.
• Thunder. Thunder is a deep sound, so it has a low pitch.
• A siren — correct. Yes!
• An aircraft rumble. An aircraft rumble is a deep sound, so it has a low pitch.
• It has a higher frequency. In general, low pitch sounds have a lower frequency.
• Its frequency cannot be measured. Frequency is a physical property that can be measured. Pitch is how we perceive it.
• It has a lower frequency — correct. Yes!
• Shrill, with a high pitch — correct. Yes!
• Deep, with a low pitch. A whistle is a shrill sound, which has a high pitch.
• Deep, with a high pitch. Deep sounds have a low pitch. A whistle is shrill, which means a high pitch.