Science Fair Project: Violin Mutes


“A violin mute is a little object that you put on your violin to quiet it,” Ian explains to me, as I pepper him with questions in Ms. Klammer’s classroom before school. I sort of know what a violin mute is in concept, but I never played the violin in school. Ian’s science experiment won Third Prize in the 34th Annual San Francisco Middle School Science Fair along with Sam’s project about microscopic invertebrates called tardigrades. (See earlier blog post).

Ian posed this question: “Does the weight of different violin mutes affect the volume of the violin?” He hypothesized that the weight of a violin mute would affect how loudly the violin plays, meaning decibel level, not necessarily brightness of tone. “Generally, heavier mutes are known to work better,” he says.

Mutes come in different weights and sizes, I learn. Some music compositions require the violin to sound quiet, or softer and muted, in parts. Ian owns a Kangaroo mute, a rolling, weighted rubber mute and a wooden mute. (Yes, the Kangaroo mute looks like a little kangaroo that sits on the violin bridge. It’s supposed to appeal to little kids, Ian tells me). He puts the wooden mute on the bridge of his violin and to tune them up, My dog has fleas, both with, and without, the mute. Even with the sound of kids playing outside, there is a slight difference. “It takes the brightness out of the sound of the violin,” he explains.

How did Ian test his hypothesis? “I would play my violin for :03 seconds, and test each mute with a decibel meter on an iPad.” He tested his violin A string five times and his violin G string five times and averaged the decibels. He tried his three mutes: the rubber kangaroo mute (2 grams), the wooden mute (4 grams), and the rolling weighted rubber mute (2 grams). He also tried clothespins clipped to the treble foot (under the A string) and clipped to the bass foot (under the G string). His findings weren’t exactly what he expected.

“My hypothesis was wrong, because I thought the mute that was heaviest would affect the decibels the most. I had to figure out that there was more than just one variable in the violin mutes. Weight wasn’t the only variable. It was the weight, the material and how the mute was positioned on the bridge.” Rubber seemed to absorb sound more than the other mutes. The kangaroo mute fit more compactly on the bridge, while the wooden mute was more spread out. Ian allowed that there could also be room for error, based on how he stroked the violin with his bow each time.

It turned out that the best store-bought mute was the kangaroo mute (2 grams). The wooden mute was heaviest (4 grams), but it wasn’t the one that brought the decibels down, or muted the notes, as much.

Ian’s conclusion? The variable of weight isn’t the only thing affecting a mute, so when buying a mute, don’t always get the heaviest one. It might not work the best.

#Science #Music

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