Building a Band: WAves
The object of this project was to build one instrument from each of the families. My group, Natalie and Mikayla, built an ukulele, chimes, and a flute. Each instrument was required to play an octave. In addition, we were able to write a science themed song to perform at the ribbon cutting ceremony for the Passive Solar Home.
String instruments:
When building a string instrument, it is important to understand how the varying string tensions can effect the tone of the notes played. Higher string tension will create a greater frequency, which will therefore give a higher pitch; likewise, lower string tension will give the opposite -- a lower frequency, and a lower pitch. String length is also a key way to alter the pitches, and is often seen on instruments such as the guitar. The shorter strings, which are often made to be thinner as well, provide higher frequencies and pitch. To create sound, the ukulele strings can either be plucked or strummed to produce vibrations. To tighten the strings, you turn the tuning picks so they pull in the excess string to make it sturdier.
Our string instrument was a cardboard ukulele. At first, we were doubtful of the resonance of the cardboard but we found that making a hollow are inside the cardboard, much like a real ukulele would create a similar sound. We also chose to construct the neck out of wood so the strings would have sturdy surface to be played on. The separation of frets determines where to place your fingers to produce different notes. We used popsicle sticks to be used as frets and placed them according to the length of our instrument. One challenge that we had was the strings. The plans for the original instrument called for rubber band strings. Well, that did not work. Every band snapped and they all sounded the same no matter how tight you made them. Luckily, my friend Poh, who is an avid violin player, was able to donate some of his spare strings. Thanks Poh! Now, are instrument was able to be tuned and played.
The first harmonic of a stringed instrument is also called the fundamental frequency. In the first harmonic, the wavelength is double the size of the length of the string. For the second harmonic, the wavelength and the string's length are equal.
Our string instrument was a cardboard ukulele. At first, we were doubtful of the resonance of the cardboard but we found that making a hollow are inside the cardboard, much like a real ukulele would create a similar sound. We also chose to construct the neck out of wood so the strings would have sturdy surface to be played on. The separation of frets determines where to place your fingers to produce different notes. We used popsicle sticks to be used as frets and placed them according to the length of our instrument. One challenge that we had was the strings. The plans for the original instrument called for rubber band strings. Well, that did not work. Every band snapped and they all sounded the same no matter how tight you made them. Luckily, my friend Poh, who is an avid violin player, was able to donate some of his spare strings. Thanks Poh! Now, are instrument was able to be tuned and played.
The first harmonic of a stringed instrument is also called the fundamental frequency. In the first harmonic, the wavelength is double the size of the length of the string. For the second harmonic, the wavelength and the string's length are equal.
Wind Instruments:
Wind instruments require an initial vibration, caused by the mouth. There are many different wind instruments covering the various note ranges. The instrument we chose was the flute. We used a pvc pipe and drilled various holes in it. One mistake we made was not measuring where we put the holes. We just randomly drilled them. However, They were all correct! So I guess my group is just crazy smart! Our flute was able to play every note and then some. Flutes are played by blowing air across the mouthpiece. The mouthpiece has a hole in the center to blow air across. The holes in the flute are different sizes and different lengths apart from each other. Our pvc pipe flute plays the notes in the chart below.
Note:
C D E F G A B C |
Wavelength (cm):
65.93 58.74 52.33 49.39 44.01 39.20 34.93 32.97 |
1/2 Wavelength (cm):
32.965 29.37 26.165 24.695 22.005 19.60 17.465 16.485 |
Frequency (Hertz):
523.25 587.33 659.25 698.46 783.99 880 987.77 1046.5 |
This is a chart of the wavelengths and frequencies of all of the notes we were required to play.
CHime Instruments:
Our chimes were created by cutting copper pipe into varying lengths. The lengths of the pipes depended on the note we wanted to reach. Below is the chart of our pipe lengths. We found these lengths online but had to modify them by ear. The instructions online were for aluminum pipes. We had to modify them by ear because copper pipe has a different natural frequency than aluminum pipe. Our pipe has a diameter of 1 ½ cm and a thickness of 2 mm. When the pipes are hit with the wooden hammer, the pipes resonate. This causes waves to travel inside the pipe, all the way through it, and out. When the waves vibrate out of the pipe, a note is created that we can then hear. Below is a list of the notes and their lengths.
Note:
C D E F# G A B C ` |
Pipe Length:
10 1/4" 9 7/8" 8 7/8" 8 1/2” 8 1/4” 7 1/2” 7 1/4” 6 3/4" |
REFLECTION:
Overall, I felt that the project went very well. My group was always on task and we tackled any problem that came our way. When our ukulele bent in half, we just fixed it without any complaints. (Well maybe a few...) One thing we could have changed was making sure that our presentation was all in order. Some things had been changed without my knowledge and that caused me to skip part of the presentation.
Another thing that I thought went very well was our time management. We were very on top of our tasks. If one of our group members was absent, we still completed that assignments way ahead of schedule.
Another thing that I thought went very well was our time management. We were very on top of our tasks. If one of our group members was absent, we still completed that assignments way ahead of schedule.