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What is sound?. February 19, 2014. How do speakers make sound?. For any sound to be made matter has to be vibrated (called the medium) As matter is vibrated it is moved back and forth producing a wave What kind? Longitudinal, consisting of compressions and rarefactions.
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What is sound? February 19, 2014
How do speakers make sound? • For any sound to be made matter has to be vibrated (called the medium) • As matter is vibrated it is moved back and forth producing a wave • What kind? Longitudinal, consisting of compressions and rarefactions
But what about the speaker? • Speakers take electrical signals and convert them into vibrations causing the speaker to move forward and then backward very quickly • This forward and back motion causes longitudinal waves to be produced • Do the vibrations cause air to be moved? • No, if true loud speakers would blow you down
Does sound travel the same way through all matter? • No, depending on how close the matter’s particles are the faster or slower the sound travels • Ex. Air – 331 m/s Water – 1,482 m/s Steel – 5,200 m/s
What about pitch and frequency? • The pitch of sound is a measure of how high or low a sound is perceived to be • This depends on how many waves pass in a given amount of time – frequency • So, the higher the pitch, the higher the frequency the lower the pitch, the lower the frequency
Are softer sounds different from louder sounds? • Yes, and no Yes, they have the same pitch No, they have different amplitude Amplitude – the distance from the resting position to the crest or trough the higher the amplitude the louder the sound