How can the same note sound different depending on who or what is producing it?


I have always thought that a note, for example G5, to be G5 because it’s a certain frequency. So if everyone is singing the same frequency, how does it still sound different from person to person and from instrument to instrument?

In: 5

When you listen to the same musical note, say a middle C, being played on a piano, a violin, a flute, or sung by a human voice, each one sounds different even though they are the same note. The reason for this lies in something called “timbre” (pronounced “tam-ber”).

Timbre, often referred to as the “color” or “quality” of the sound, is what allows us to distinguish different types of sounds even when they are the same pitch and loudness. The timbre of a sound is influenced by a few factors:

Harmonics: When you pluck a guitar string or blow air into a flute, it doesn’t just produce one single frequency (the fundamental frequency, which corresponds to the note you’re playing). It also produces a series of higher frequencies at the same time. These are called “harmonics” or “overtones”. The presence, absence, and relative strength of these harmonics contribute to the timbre of a sound.

Attack and Decay: How quickly a sound reaches its full volume (the attack) and how it fades away (the decay) also affect the sound’s timbre. For example, a piano has a fast attack and a slower decay, while a violin can have a slower attack and maintain a note for longer.

Resonance: Different instruments have different shapes and are made from different materials, which can amplify or dampen certain harmonics. For example, the body of a guitar or the soundboard of a piano can resonate and influence the sound that is produced.

These factors all combine to create a sound’s unique “fingerprint”, allowing us to tell the difference between the same note being played on different instruments or sung by different voices. This is also why, for example, a high-quality violin sounds different from a lower-quality one, even when playing the same note – the shape, materials, and craftsmanship of the instrument can significantly influence its timbre.

The central frequency of a G5 is the same frequency regardless of who or what is producing it, but the overall “character” of the note (what we call Timbre) varies from instrument to instrument. There will be other frequencies that are multiples or fractions of the central frequency, and the pattern of what other frequencies can be heard, how loud they are relative to the central frequency, and how long they last all make a difference on the final sound.

It mostly has to do with harmonics. When you play any note on anything that makes a sound, you’re producing more than just that note. If you play a note with a frequency of 100Hz, then you’re also inadvertently also producing notes at frequencies of 200Hz, 300Hz, 400Hz, and every integer multiple of the base frequency, that we call the **fundamental**. It is the various sound level differences between these peaks that determine the sound of the instrument. Clarinets have a lot of sound at the fundamental, but very little sound at the overtones. As a result, it sounds very similar to a sine wave. Guitars on the other hand produce a lot of overtone sounds, creating a brighter timbre. But if you use an equalizer to remove all the frequencies above the fundamental, a guitar sounds very similar to a clarinet.