What is sound?
How do you get up in the morning? E.g. birds chirping, alarm on your phone? Sound is what you hear. Sound is everything that we hear: a clock ticking, a door slamming, a dog barking, a car changing gear on the hill, the wind in the trees, a voice speaking in the next room and another voice singing in the house across the road. It is everywhere and very important. We need it to talk to and understand other people, to pick up alarms and what they mean to us. E.g., a phone ringing says someone is calling, a fire alarm warns about a fire.
How is sound produced?
Sound is produced by vibrations. The back and forth movement of an object is known as vibrations.
Properties of Musical Sound
- Amplitude (intensity/volume) - loudness or softness of a sound.
- Low waves - soft sounds
- High waves - loud sounds
- Volume is relative to the other sounds around it.
- It is measured by decibels (dB).
- Frequency (pitch)- highness or lowness of a sound.
- Fast vibrations - high pitch
- Slow vibrations - low pitch
- Small objects vibrate faster and have higher pitches.
- Large objects vibrate slower and have lower pitches.
- It is measured by hertz (Hz) or cycles per second.
- Timbre (tone colour/quality) - the unique quality of musical sound.
- The ability to distinguish one instrument from another.
- It is described using words like bright, dark, brilliant, mellow, rich.
- It is determined by many factors, including:
- the skill of the performer
- the size of the instrument
- the shape of the instrument
- how sound is produced (blowing, plucking, striking, etc)
- Duration - the length of time a musical sound lasts.
- How long or short sounds are.
- It is measured by beats per minute (bpm).
