Here is a brief explanation of how my pan flute works (or at least how i think it works). I'm still a little confused on the whole wavelength thing, but I feel like i did a pretty decent job of faking it in this explanation.
I constructed my musical instrument (a modified version of the Pan Flute) by cutting various lengths of PVC piping, duct taping them together and blocking off the bottom end of each piece of piping with a ball of clay.
I started out cutting five different lengths of .5” in diameter of PVC piping. The approximate lengths I used for each piece of piping respectively were 9.5”, 8.5”, 7.5”, 7”, and 6.5”. I then sanded the ends of each pipe, laid the pipes out so that the tops of each pipe is aligned with each other while the bottoms end staggered, and then taped the pipes together.
After constructing my pan flute thus far, I struggled with finding a material to block off the bottom end of each pipe. I was able to produce a pitch with each tube when I placed the palm of my hand on the end of each tube separately, but could not find a material that was capable of reversing the travel of the sound waves. I finally found the solution to this problem while looking online.
The answer was clay. All I had to do to block of the end of each pipe, thus enabling myself to create a pitch, was to place a wad of clay at the bottom opening of each tube. This solved my problem, and I was able to create five different pitches from the five pipes without placing my hand over the opening of each one.
The physics behind this instrument can be identified through the principles displayed by wavelengths traveling through a pipe with one closed end and one open end (the end with the clay being the closed end). Because one of the ends of the pipe is open and one is closed, the open end is an anti node and the closed end is a node. Because one end is a node, and the other end of the pipe is an antinode, only odd numbered harmonics are capable of being produced within the pan flute. As air is blown across the top of an individual pipe, the air particles travel down the column as a wavelength and as they meet the clay at the end of the pipe, are reflected back out the pipe, thus creating a sound.
The differences heard in the different pitches of each pipe can be understood through the definition of frequency. Frequency is defined as “the number of cycles or vibrations per unit of time; also the number of waves produced per unit of time” (Serway, Raymond A. and Jerry S. Faughn 954). As the frequency is increased the pitch becomes higher. In my pan flute, the shorter pipes have higher pitches than the longer pipes. Keeping in mind the definition of “frequency” we know that this is because a cycle of vibrations will complete itself faster in a shorter pipe than in a longer pipe. Thus, shorter pipes create higher pitched sound.
Directions on making a pan flute taken from: Linda Barnhart, and http://www.teachervision.fen.com/tv/printables/Bose_Master_7.pdf