Understanding Sound (04:06)

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A hemi-anechoic chamber isolates a sound and allows one to witness its effects. Frequency is related to how much a sound moves the air around it.

Individual Sound (02:58)

Every object produces a unique sound. The sound of the bell in Big Ben is easily recognizable to Londoners. The sound is created by air being pushed away from the vibrating metal of the bell.

What is Frequency? (09:02)

The frequency of objects was first studied by German physicist Ernst Chladni. He developed an experiment to identify different frequencies produced by a single object. Big Ben's natural frequencies are aligned in a harmonic relationship, which makes for a pleasant noise.

Sound Resonator (03:16)

A resonator generates waves of specific frequencies. In a violin, the wood body is the sound resonator as it amplifies the frequency from the vibration of the strings. Most musical instruments have a resonator that gives it a distinctive sound.

Shaping Sound (07:38)

The human voice has a greater ability to shape sound than any man-made instrument. Opera singer Lesley Garrett visits a throat specialist to have her larynx examined. The throat and mouth is the sound resonator for the human voice.

Ocean Sounds (06:03)

The nature of sound in the ocean is hidden from everyday life. Water is an acoustic mirror; sound underneath the surface stays underneath. A marine biologist explores how sound behavis underwater.

Range of Hearing (04:36)

Many sounds exist outside the range of human hearing, which is about the range of a piano. Dolphin communicate using ultrasound.

What is Infrasound? (07:28)

Infrasound is too deep for humans to hear. Volcanic eruptions create a supersonic sound that is heard as an explosion and an infrasound that humans cannot hear.

Credits: Making Sound (00:46)

Credits: Making Sound