Tubular bells

What you can do here
Hit one pipe after another with the mallet. Each of them produces a different sound from the musical scale. Make the bells play by hitting them near the upper ends or closer to their centres. Determine how the timbre changes depend on the spots you’re hitting. The bells are tuned within the same octave. You can play a simple melody:
g e e f d d c e g or
c d e c c d e c e f g e f g g a g f e c or
e e f g g f e d c c e d d d d e c d e f e c d e f e d c d g.

How it works
By hitting the pipe you make it oscillate and the vibration propagated through the air reaches your ears. The so-called standing wave is formed whose length is determined by the length of the pipe. The wave length is closely related to the wave frequency, which in turn determines the sound pitch; thus, the shorter the pipe, the higher the sound.

Interesting facts
Tubular bells are a musical instrument used for instance by symphony orchestras. They gained recognition in popular music after Mike Oldfield used them in his 1973 album Tubular Bells (over 15 million copies sold worldwide).