"Sounds of Music"

            For my “Sounds of Music” project I was assigned to make a percussion instrument.  I chose the xylophone, and it turned out to be an easy instrument to build.  I used PVC pipes for the base and four elbows for the stand.  There are 10 tubes total, of which 8 make a scale.  The metal tubes are cut at different lengths giving the different pitches.  There are also 7 rubber bands holding the tubes in place and giving the xylophone structure.  The percussion instruments make sounds through hitting the tubes.

           

            There are certain details that attribute to the making of sound on the xylophone.  The first is that both ends are free, allowing the tubes to vibrate when hit.  The speed of sound (m s^-1) for the steel tubes is 5050.  To determine the pitch of the tube you have to determine the length of the tube.  The longer the tube the lower the pitch and the shorter the tube the higher the pitch, there is also the question of what is your scale.  Once you figure out the length of the first note then you can use the same equation to figure out the rest of the notes.  Upon figuring out the lengths you can cut and try.  Comparing to the piano scales is a good way to go.  Then for the right pitch you want after calculating the length and all you hit the tubes with something like a mallet.  Hitting the tube in different spots will give you different volumes of the pitch and different pitches.  The wavelengths occur beneath the tubes and some around and this is the vibration of the tube and the air pushing and pulling creating this effect, the air particles around the tubes do this..  These points are called antinode, there is the center of the tube and then the two ends.  These go from the fundamental frequency to the higher as you hit on different spots.

            The xylophone works through the vibration after the hit and the ends being free allowing the tubes to go back and forth and create this beautiful sound that can create music.  This project is quite easy and teaches you many different things about the physics world we live in.