For the sixth project we completed in STEM, we were tasked with creating musical instruments. We had to research, design, and build three instruments. We had to build one wind instrument, one chime instrument, and one string instrument. We learned about how these instruments work and what is required to make each instrument play a full 8 note scale. My group, (Tara Shotz, Eliza Roesler, and Marilynn Hunt) and I made a guitar, a xylophone, a set of drums, and an instrument using bottles. Using all the information we learned, we were able to make 4 instruments that looked and sounded great.
Refection
For this project we got to choose our own groups again. This was very good in my group's case, because we all knew that we would work really well together. Through out this project, our group had some pits and peaks. First, we all cooperated really well together. We rarely argued and also maintained good attitudes towards each other. We also combined everyone's ideas into our instruments which made them look and sound really good. Another thing that I did well was staying optimistic. I can become very pessimistic at certain times, especially when I am stressed out. Throughout the duration of this project, I did not stress out and working with my friends helped me stay optimistic through the whole project. One thing that could have gone better was the guitar. We were on a very tight time schedule and as we were trying to tune our guitar, one of the strings snapped. This caused a huge problem because we ran out of that type of string and we had to use a different string with a different tension. In the end we figured out how to solve the problem, and our guitar turned out really well. Another part of this project that I had a hard time with was the information about waves. Coincidentally, we were learning about waves in math as well. We were using the same terminology (frequency, amplitude, etc.) but in a completely different context, involving sine and cosine waves. This caused me to become very confused because the concepts were very similar to what we learned in STEM. I had some trouble distinguishing between the two subjects and in what context to use both waves. Another thing that threw me off was that we were measuring the same waves, but with two different units. In math we used radians but in physics we used regular numbers. In the end, these differences became clearer to me and I understand them a lot better now. Overall, this project was very successful, and I am very proud of my group's work.
For this project we got to choose our own groups again. This was very good in my group's case, because we all knew that we would work really well together. Through out this project, our group had some pits and peaks. First, we all cooperated really well together. We rarely argued and also maintained good attitudes towards each other. We also combined everyone's ideas into our instruments which made them look and sound really good. Another thing that I did well was staying optimistic. I can become very pessimistic at certain times, especially when I am stressed out. Throughout the duration of this project, I did not stress out and working with my friends helped me stay optimistic through the whole project. One thing that could have gone better was the guitar. We were on a very tight time schedule and as we were trying to tune our guitar, one of the strings snapped. This caused a huge problem because we ran out of that type of string and we had to use a different string with a different tension. In the end we figured out how to solve the problem, and our guitar turned out really well. Another part of this project that I had a hard time with was the information about waves. Coincidentally, we were learning about waves in math as well. We were using the same terminology (frequency, amplitude, etc.) but in a completely different context, involving sine and cosine waves. This caused me to become very confused because the concepts were very similar to what we learned in STEM. I had some trouble distinguishing between the two subjects and in what context to use both waves. Another thing that threw me off was that we were measuring the same waves, but with two different units. In math we used radians but in physics we used regular numbers. In the end, these differences became clearer to me and I understand them a lot better now. Overall, this project was very successful, and I am very proud of my group's work.
Content
wavelength (λ)- The distance from crest to crest of a wave
amplitude (a) - Displacement from equilibrium to the crest in a wave
longitudinal wave - Compresses and expands as it moves forward (example: sound)
transverse wave - Moves up and down as it moves forward (example: light)
frequency (f) - The number of waves or vibrations in a unit of time
period (T) - time between waves/vibrations. Time it takes for one wavelength to pass
wave speed (v) - Rate at which a wave travels
wavelength (λ)- The distance from crest to crest of a wave
amplitude (a) - Displacement from equilibrium to the crest in a wave
longitudinal wave - Compresses and expands as it moves forward (example: sound)
transverse wave - Moves up and down as it moves forward (example: light)
frequency (f) - The number of waves or vibrations in a unit of time
period (T) - time between waves/vibrations. Time it takes for one wavelength to pass
wave speed (v) - Rate at which a wave travels
Our Instruments
Xylophone (vibration): Our xylophone is a chime instrument. The longer the pipe is, the lower the note is. We made our xylophone by finding a pre-cut piece of pipe and hitting it with a mallet to see what note it makes. From there we used a chart that told you what numbers to multiply the original length with to create different notes. Our original pipe, the longest one, was 33 centimeters long and an E4. We decided to make our xylophone have one octave of notes. The highest note is E5 at 23.43 centimeters. All of the other pipes are varying in lengths that are between 33 and 23.43 centimeters, but the higher the note is, the shorter the pipe length. The reason why shorter pipes make higher pitched sounds is because there is less time for the sound wave to travel through the pipe. The wave lengths are compressed, which creates a higher pitched sound. That means that the longer the pipe, the more spread out and longer the sound wave will be. If the wave lengths are more compressed, they vibrate faster. The more time they have to rarefy, the slower the waves vibrate. |
Here is a table of the length of each chime and the note it creates:
E₄ - 33 cm
F₄ - 31.02 cm
G₄ -29.37 cm
A₅ - 28.71 cm
B₅ - 27.06 cm
C₅ - 25.41 cm
D₅ - 24.09 cm
E₅ - 23.43 cm
E₄ - 33 cm
F₄ - 31.02 cm
G₄ -29.37 cm
A₅ - 28.71 cm
B₅ - 27.06 cm
C₅ - 25.41 cm
D₅ - 24.09 cm
E₅ - 23.43 cm
Guitar (string):
Our guitar uses vibrations and tensions to play a 12 note scale. Our guitar classifies as a string instrument and plays a total of 12 notes. It ranges from an F3 to a C4. To reach these notes we have included 4 strings, each having an open note, and two frets to play. Each fret plays one note higher than the last. We tuned the open string by tightening screws that keep the strings in place. We then used the guess and check method with a tuner to place the frets. To find the lengths of the open strings, we used the provided wavelength chart and calculated the length of the longest string. We then just placed blocks of wood on the other open strings to shorten them, and played with the tensions using a tuner. The vibration resonating through the large, wooden box makes the sound louder and the sound waves from plucking of the strings becomes audible. When the string is shorter or tenser, you get a higher not, and when it is longer or looser, you get a lower note.When the string is tight and short the vibration is small and vibrates in a smaller proximity, producing a higher note. When the string is long and loose, the vibration is large and wide, producing a lower note. |
Here is a table for our guitar:
F3 - 98.78 cm
G3 - 88.01 cm
A3 - 78.31 cm
B3 - 69.885 cm
C4 - 65.938 cm
D4 - 58.74 cm
E4 - 52.33 cm
F4 - 49.39 cm
G4 - 44.005 cm
A4 - 39.205 cm
B4 - 34.925 cm
C5 - 32.965 cm
F3 - 98.78 cm
G3 - 88.01 cm
A3 - 78.31 cm
B3 - 69.885 cm
C4 - 65.938 cm
D4 - 58.74 cm
E4 - 52.33 cm
F4 - 49.39 cm
G4 - 44.005 cm
A4 - 39.205 cm
B4 - 34.925 cm
C5 - 32.965 cm
Bottles (wind):
The bottles use sound waves, vibrations, and different frequencies to create sound waves, which create notes. Our bottles are classified as wind instruments. For all wind instruments, it is essential to create vibrations. The vibration can be from friction (example: reed in a clarinet), or from splitting air (example: flute). In the case of our instrument, we are splitting the air. Half of the air goes over the bottle and the other half goes into the bottle. This creates each bottle’s unique sound (along with the amount of water/fluid in it). The vibrations created must travel through some kind of tube to actually create a certain note. To find how long the tube must be in order to create a certain note, you take the wavelength of the note and divide it by four. Wind instruments require ¼ th of the original wavelength to create the certain note. To complete one full sound wavelength, the wave must travel from high pressure, to equilibrium, to low pressure, then back up to equilibrium. A wind instrument only uses one fourth of the complete wavelength to create notes. The high pressure is created at the top of the bottle (where you blow into it) and the neutral pressure is where the sound waves exit. If a note has a wavelength of 131.87 cm (middle C), then in a wind instrument the wavelength must be 32.97 cm. This means that the pipe must be 32.97 cm long in order to create that note (can place a hole at same distance for same effect). The bottles we used play notes that range from a C4 to a C5. Our group decided to change the notes by adding different amounts of water into each bottle. The more water that was in the bottle, the higher the note. This is the result of the sound waves vibrating. The bigger the bottle/space provided, the longer it will take for the pressure inside to build up (vibrate) which results in longer frequencies, causing deeper notes. As you add in water, the sound waves’ space becomes restricted and they will start to move faster causing a higher frequency. This results in higher notes.
The bottles use sound waves, vibrations, and different frequencies to create sound waves, which create notes. Our bottles are classified as wind instruments. For all wind instruments, it is essential to create vibrations. The vibration can be from friction (example: reed in a clarinet), or from splitting air (example: flute). In the case of our instrument, we are splitting the air. Half of the air goes over the bottle and the other half goes into the bottle. This creates each bottle’s unique sound (along with the amount of water/fluid in it). The vibrations created must travel through some kind of tube to actually create a certain note. To find how long the tube must be in order to create a certain note, you take the wavelength of the note and divide it by four. Wind instruments require ¼ th of the original wavelength to create the certain note. To complete one full sound wavelength, the wave must travel from high pressure, to equilibrium, to low pressure, then back up to equilibrium. A wind instrument only uses one fourth of the complete wavelength to create notes. The high pressure is created at the top of the bottle (where you blow into it) and the neutral pressure is where the sound waves exit. If a note has a wavelength of 131.87 cm (middle C), then in a wind instrument the wavelength must be 32.97 cm. This means that the pipe must be 32.97 cm long in order to create that note (can place a hole at same distance for same effect). The bottles we used play notes that range from a C4 to a C5. Our group decided to change the notes by adding different amounts of water into each bottle. The more water that was in the bottle, the higher the note. This is the result of the sound waves vibrating. The bigger the bottle/space provided, the longer it will take for the pressure inside to build up (vibrate) which results in longer frequencies, causing deeper notes. As you add in water, the sound waves’ space becomes restricted and they will start to move faster causing a higher frequency. This results in higher notes.
C4 - empty
D4 - 3 cm
E4 - 6 cm
F4 - 7 cm
G4 - 9 cm
A4 - 10 cm
B4 - 12 cm
C5 - 12.5 cm
D4 - 3 cm
E4 - 6 cm
F4 - 7 cm
G4 - 9 cm
A4 - 10 cm
B4 - 12 cm
C5 - 12.5 cm
Here are a few diagrams to help explain the relationship between ¼ th wavelengths and wind instruments:
Drums (vibration):
Our drums are a vibration instrument, but we did them a little differently. We started out trying to make them like the steel reggae-style drums like the ones in “Under the Sea”, but we had some trouble. We tried to use a cupcake tin to make the note range and were trying to modify the note by hammering it so it would produce a lower or higher sound. This did not work out, and each part sounded like the same metal bang. We also couldn't really get a good read on what note it was making with that metal bang. We decided since we had 3 other instruments that this one would be sort of a background beat, much like a simple drum set with a pot lid as a cymbal, a garbage can as one of the big drums, and a metal platter tray as a sort of snare. We also have two drumsticks made out of wooden dowels and another wooden dowel with a paper towel and duct tape tip on the end for the big drum (it makes a different sound). |