Although the combination of music and chemistry is not technically called “Orchemistra,” there is clearly a relationship between the construction of an instrument and the sound it produces. The science of sound in itself is an amazing thing. We as humans have had relatively technically advanced instruments for a long time, but only in the most recent century or two have we been able to express what is actually happening in physical and chemical terms. Sound is generally produced by the frequencies of vibrating waves, as explained here. The longer wavelengths have lower energy and the less frequency. The research that has been done also tells us that the lower the frequency, the deeper the pitch. This is interesting since all instruments are produced with specific materials and with specific sizes to produce specific sounds. The more open an instrument is, the deeper the pitch since the traveling wavelengths from the vibrations tend to be very long.
For instance, certain violin-like instruments are created with larger bouts so the waves can travel farther distances, causing them to lose energy along the way and have longer wavelengths that produce a deeper pitch when escaping through the f-holes. These larger instruments also allow for more waves to be constructive and destructive. The constructive waves obviously will produce a louder and more noticeable sound, when the destructive waves cancel each other out to produce little to no sound. The thickness of the string also affects the sound produced. As a string gets thicker, it becomes stiffer since it takes more energy to vibrate it. This affects the wavelength produced, since the thicker strings will vibrate less frequently and in turn produce longer wavelengths. The opposite holds true for thinner strings since they are able to vibrate very frequently in a certain period of time.
When it comes to another string instrument, the piano, it is essential to know the parts that make it up. A piano has its strings struck with hammers to create a more earthy tone. As a key is pressed, many moving parts go into motion to make a hammer hit the certain strings. A felt piece above the strings called a damper is lifted as the key is pressed. The damper will silence the strings when the key is let go. The strings are made up of steel wire. The strings vary by pitch, with the middle range notes having as many as 3 strings to each of them, and the lower notes having a coiled copper wrapping around them. These strings will echo across a large soundboard in the piano, giving it the unforgettable, indistinguishable sound a piano has. In between is a large cast iron plate designed to withstand the tons of tension that the steel strings deploy. Pedals at the bottom of the instrument can affect how a damper is sustained, and even how many strings are hit for any given note. However, this is only the case for grand pianos. With smaller, upright pianos, the hammers strike the strings sideways. Older instruments in the piano family, such as the clavichord, are struck with a different material of strings, offering a more guitar sound. There is one thing these instruments all have in common: a dependency on material science. Studies, such as this one, have shown that chemically altered wood offers unique sounds with violins. This could apply to the soundboard of the piano, a crucial piece that gives the instrument its legacy.
As another example, the brass family is quite unique. There are many kinds of modern brass instruments, but the majority of them are some modification of a trumpet, a French horn, a euphonium, a trombone, or a tuba. One thing to note about these instruments is that some (like the trumpet) have mainly cylindrical (or non changing in diameter) bores, while others (like the horn) have nearly entirely conical (constantly increasing) bores. This difference, although seemingly insignificant, has a great impact on the sound. The conical bore results in irregular sound waves, and this sound is often described as mellower and darker than the bright and crisp sound of a cylindrical bore instrument.
Another thing you may notice about brass instruments is that a lot of brass instruments appear to be different colors, and most don’t look like brass. In fact what you are seeing is the plating, and the lacquer coating, both of which are not necessary. Brass instruments can be plated with nickel, silver, gold, platinum, rubidium, and other metals. The mouthpiece can also be plated with these metals. Finally, another difference in composition is the brass alloy used for the bulk of the instrument, which can be made from gold brass, rose (copper) brass, along with many other types. All of these discrepancies between different brass instruments are almost purely for aesthetics, despite some peoples’ claims about difference in tone or sound. Not to mention, a good brass player can bring a good sound out of any instrument by adjusting the way he or she holds their lips in order to play.