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332

FIND OUT MORE. Music 330–331 • Orchestra 335 • Sound 176–177

1 GRAND PIANO

When a musician hits a key, a

hammer strikes a string inside the

piano. The string vibrates, making

a sound. In a grand piano the

strings are arranged horizontally.

In an upright piano they are

arranged vertically, to save space.

1 TRUMPET

This brass instrument is played by blowing air through the

mouthpiece into a narrow metal tube. Pressing the valves alters

the length of the column of air, producing different notes.

Tuning pin adjusts

the tautness of the

string to produce

the correct pitch

Felt-covered

hammer makes the

string vibrate

Keyboard has 88

keys. The difference

between each is

called a semitone

HOW DO INSTRUMENTS GENERATE SOUND?

An instrument creates sound when part of it vibrates

rapidly. The column of air inside a wind instrument,

the string of a string instrument, or the stretched skin

of a drum all vibrate when played. This vibration

produces sound waves in the air, which we hear as

musical notes.

HOW DO ELECTRONIC INSTRUMENTS WORK?

Electronic instruments – such as electronic keyboards –

do not make actual sounds in the way an acoustic

instrument does. An electronic instrument produces

an electric signal that is transmitted to an amplifier

and then broadcast through a loudspeaker. Using a

process called synthesis, electronic instruments imitate

acoustic instruments or create their own sounds.

1 DRUM KIT

Drums belong to the percussion family. This standard kit is used in

popular music, such as jazz and rock. A drummer needs coordination and

energy as they often hit several drums at once using different rhythms.

4 VIOLIN

Like most string instruments,

the violin has four strings, each tuned

to different notes. It is played either with a

bow or by plucking it with the fingers.

Wide, flared bell to

broadcast the sound

Floor tom

Bass drum

Cymbal Tom-tom

Valve

Violin bow

Hi-hat

Tuning peg

Mouthpiece

Musical Instruments

We use a huge range of instruments to produce sounds and make

music. Some are simple pieces of solid wood or hollowed-out

seashells. Others are highly technical or electric. Instruments

vary around the world and each has its own character.

HOW ARE MUSICAL INSTRUMENTS CATEGORIZED?

Acoustic instruments generate sound physically and

electronic instruments create sound electrically. There

are four acoustic groups: percussion (hit or shaken),

wind – woodwind and brass – (blown), string (bowed

or plucked), and keyboard (played by striking a key).

Snare

instruments