Science Olympiad is a multidisciplinary competition in which teams of up to 15 students compete against teams from other schools in more than 20 events at the regional, state, and national levels. Events rotate each year, ensuring teams a fresh slate of science and applied science challenges. Here, four-year Science Olympiad veteran Soren Schlassa shares his experience in a particularly challenging event: Sounds of Music.

Sounds of Music has, as my Science Olympiad team’s head coach put it, a reputation as “the mother of all build-ing events.” Two students each build an

instrument from scratch, arrange and perform a duet and an assigned piece, give a brief interview on the construction of their instruments, and take a test on the physics involved. I had never encoun-tered a music-themed Science Olympiad event in my previous three years of participating and was intrigued by the challenge.

Four years of playing classical guitar had given me a basic understanding of music theory. My part-ner, Katie Dillon, had a much more comprehensive knowledge than I, which aided her in constructing her instrument: a bass dulcimer. After coordinating a timeline that would allow us to practice together before the competition, we went our separate ways to build our instruments.

I decided to build a xylophone, and I knew I wanted to use metal. I soon realized that metal bars require complex shaping to produce good tone quality, so I decided to build a pipe metallophone. My father and I tested copper and aluminum pipes of varying diameters, lengths, and thicknesses we’d bought from a local hardware store, as well as some old copper pipes from the garage. After kneeling in the kitchen for hours, striking various pipes, checking their tuning, and noting their tone quality, I decided to use the copper from the garage. Not only did it have slightly better tone quality, but it was free.

The rules allowed a range of just over three octaves: 27 notes, from F3 to G5. The minimum was one octave: C4 to C5. If my xylophone could produce the full range of notes, we would earn extra points, and I’d have more versatility in my perfor-mance. This meant that I needed 27 pipes, which

would eventually range in length from over half a meter to less than 25 centimeters.

Shaping the NotesBefore I started building my xylophone, I had to learn about the physics of tube idiophones (instru-ments that produce sound by the vibration of the instrument itself, without the use of membranes or strings): how to tune them, how to determine what length the pipes should be, how to mount them to bring out the desired notes’ fundamental frequency. In my research, I found an equation used to esti-mate the length of a pipe, taking into account the diameter and wall thickness of the pipe, the speed of sound in the material, and the desired frequency.

After researching the speed of sound in copper (3700 m/s) and measuring the diameter and wall thickness of my pipes with a caliper, I used the equation I’d found to estimate the length of pipe I needed for each note. Actually cutting and tuning the pipes turned out to be quite a process. I cut each pipe with a handheld pipe cutter, the kind that you tighten onto the pipe, turn, tighten more, turn, and repeat until the pipe breaks. Then I checked the pipe’s tuning with my guitar tuner. If the note was flat, that meant the pipe was a little too long, so I would take it to the garage to grind it down with my grandfather’s bench grinder.

Although I wasn’t yet sure exactly how the pipes would be mounted, or to what, my father and I drilled holes in them just in case. In my research, I had learned about the concept of nodes, points along a wave where the amplitude is zero. To emphasize a note’s fundamental frequency in a pipe, I learned that I needed to mount the pipes at nodes, which, for all pipes, are located at 22.4% of the pipe’s length from each end. That is where we drilled the mounting holes.27

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Finishing TouchesNow I had to deal with the appearance. Points would be awarded for workmanship, so my 27 oxidized, ugly pipes had to be cleaned. Research and testing yielded citric acid mixed with salt as the most effective way to clean them. Over the course of a week or so, I scrubbed one pipe at a time in the kitchen sink, then discovered to my dismay that the pipes were oxidizing again. It turned out that I needed to neutralize the acid and then apply a store-bought, paint-on coating to stop the pipes from oxidizing.

In one night, in a race against oxidation, my father and I scrubbed the pipes with citric acid, neutralized them with baking soda and water, scrubbed them with a foul-smelling polish, and finally scrubbed them with isopropyl alcohol to remove the polish. We then hung them up on a piece of fishing line across the garage, using binder clips to keep them from sliding together, and painted them with a coat-ing to prevent oxidation. After two coats, the pipes were ready to be mounted.

We stuck two lengths of adhesive-backed weather strip-ping, which struck a good balance between dampening the notes and allowing them to ring, to the top shelf of a rack we bought from Costco. Zip ties—white for naturals and black for sharps—connected the pipes to the rack and weather stripping through the holes at the nodes.

The final step of construction was to find mallets with which to play the xylophone. After experimenting with everything from wood to my fingernails, we found an especially good option: screwdrivers whose handles had a plastic core and rubber coating. These provided a loud enough sound without too much harshness. Once we had finalized the mallets, there was a moment when I turned around, looked at my dad, and said, “Are we done?” After some confused blinking and mumbling, we realized that we were indeed done but also that it was very late and not at all the correct time to begin learning to play the instrument. The sense of accomplishment came the next morning, when I couldn’t stop playing it.

In the week before the competition, Katie and I arranged and learned two duets. One piece, St. Anthony’s Chorale,

was required. For the other, we combined In the Hall of the Mountain King by Edvard Grieg and Tubular Bells by Mike Oldfield into a piece we titled In the Hall of the Tubular Bells. It wasn’t until the night before the competition that we got both pieces down.

At the competition, Katie and I were the first of the 39 teams to perform for the judges. The performance went well, and, after all we’d done and learned as we planned, constructed, and played these instruments, the interview and written test were a breeze. It was the awards ceremony that heralded the excitement and satisfaction of a second-place finish.

The xylophone is still in my living room, where my dad or I will walk by and play a few notes most days, though I’ve mostly lost my ability to play it compared to the official performance. Making this xylophone was quite an experi-ence, but I think next year I’ll choose a different event.

Soren Schlassa is a sophomore at pacific ridge school in carlsbad, ca, where he participates in model un and science olympiad. in his free time he enjoys doing math homework, playing frisbee, hiking, and backpacking. he looks forward to attending the school for ethics and

Global leadership in Washington, dc, this fall.

Learn more about Science Olympiad at http://soinc.org.

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