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After reading this section you will be able to do the following:

  • Explain what three things cause the differences in sounds.
  • Discuss why some sounds are pleasing and others are not.

Why are sounds different?

As you know, there are many different sounds. Fire alarms are loud, whispers are soft, sopranos sing high, tubas play low, every one of your friends has a different voice. The differences between sounds are caused by intensity, pitch, and tone.

What is the difference between music and noise?

Both music and noise are sounds, but how can we tell the difference? Some sounds, like construction work, are unpleasant. While others, such as your favorite band, are enjoyable to listen to. If this was the only way to tell the difference between noise and music, everyone’s opinion would be different. The sound of rain might be pleasant music to you, while the sound of your little brother practicing piano might be an unpleasant noise. To help classify sounds, there are three properties which a sound must have to be musical.

A sound must have an identifiable pitch, a good or pleasing quality of tone, and repeating pattern or rhythm to be music. Noise on the other hand has no identifiable pitch, no pleasing tone, and no steady rhythm.