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The Challenge: Make musical instruments



We made string, woodwind and percussion instruments.

Stringed instruments
The pitch of a stringed instrument depends on the tension and the length of the string. In most stringed instruments the pitch gets higher when the player moves their hand closer to the bottom of the string making the vibrating area shorter. However, Mike's double bass depended on changing the tension of the string to obtain each note. In many stringed instruments, the strings themselves only produce a small fraction of the sound that is heard. The rest is due to resonance from the body of the instrument vibrating in sympathy with the strings. Mike's double bass had a huge box and a long string which gave it a very low pitch.

Wind instruments
These instruments work by using vibrating columns of air that amplify an initial sound. In all wind instruments, the length of the column of air determines the general pitch of the instrument. That is why the panpipes played by Ellen used bamboo tubes cut to different lengths to produce various notes. In order for a column of air to vibrate, something must start it going. The small sound produced by blowing over the top of each panpipe tube is greatly amplified within the tube, in much the same way as the body of a stringed instrument amplifies the sound from the string.

Percussion instruments
The sound of a percussion instrument comes from striking two things together. They can be the simplest type of instrument because usually very few parts are needed to produce an amplified sound. Our scientists made some drums from old barrels. When struck, the skin of the drum vibrated and was then amplified by the barrel to give out a sound.