How do clarinets work?

When a clarinettist surrounds the clarinet’s mouthpiece with their lips creating an airtight seal and blows, the air is pushed through the reed making it vibrate rapidly. These vibrations are projected by the bell and to our brains, the vibrations are registered as sound, thus the musical notes we hear.

As you may know, a clarinet is made up of three main parts; the mouthpiece, the bore and the bell. The mouthpiece carries a reed that when it vibrates produces sound, the bore has all the keys that manipulate the sound and the bell projects the vibrations produced by the reed. To comprehend how a clarinet works, you need to understand what sound is. Sound is a result of fluctuations in air pressure and in the clarinet’s case, air blown into the instrument makes the reed vibrate at innate frequencies causing a soundwave that travels through air particles. This soundwave is projected by the bell. To learn about the details of how a clarinet works, keep reading.

Vibrations explained

Now that we’ve explained what sound is, understanding how vibration occurs and how it becomes sound is important. To our brain, vibrations in the air particles are interpreted as sound. Just like how a string vibrates when it is plucked or a bow is run across it, vibrations also occur when air is blown through a clarinet. So, during playing, when a reed vibrates, it causes the air next to it to vibrate at a similar speed and that air causes the air next to it to vibrate and so on until the air particles next to your ear are vibrating.

Your brain then interprets these vibrations as sound and in turn, you hear the musical note produced by the instrument. Sound production, therefore, depends on the presence of air. So, for a clarinettist to produce a fuller, warmer and louder sound they need to make the reed vibrate as rapidly as possible.

Parts of a clarinet that are crucial for sound production.

The acoustics of a clarinet is majorly determined by the bore, tone holes, mouthpiece and reed. Air that vibrates in the bore is due to the air blown through the reed and mouthpiece and it is this vibrating air that produces sound. The frequency at which the air vibrates is decided by the dimensions of the bore, which can be altered by the side holes.

The table below has summarized the major parts of a clarinet and their contribution to a clarinet’s sound production.

Clarinet part.	How it contributes to sound production.
Mouthpiece	This is where the reed is kept and it is the part where the musician blows air into.
The barrel	It connects the mouthpiece to the upper joint and its job is to funnel air through the clarinet.
Upper joint	The part where the left hand is placed and it determines the pitch of the sound produced.
Lower joint	The part where the left hand is placed contains the socket, cork tenon and keys that determine the kind of sound produced.
Bell	The flared end that projects the sound produced.

How a clarinet produces sound. (How a clarinet works)

Now that we’ve discussed how vibrations occur leading to sound production, let’s see how that applies to a clarinet.

To produce a soundwave in the clarinet, energy (air blown) is released from the player’s mouth and the reed and mouth act like a valve transmitting that energy. When playing softly, the reed moves gently without touching the tip of the mouthpiece. While playing loudly, the reed moves far enough to completely close the end of the clarinet tube or mouthpiece during every vibration cycle.

For the vibration in the bore to continue taking place, energy must be released into the bore at the perfect time during each vibration cycle. Also, this will only work if the vibration frequency of the player’s lip and the reed is higher than the vibration frequency in the clarinet. Understand that vibration of the reed is crucial for sound to be produced. Without proper reed vibration, a clarinet cannot sound even if the correct fingering is applied.

It is important to note that the health of the reed will also affect the sound quality produced. Overused, warped, cracked or chipped reeds will produce squeaky and flat sounds. In addition to that, the strength of the reed will determine how quickly the reed restores its shape after being deflected by air when the instrument is played.

Factors that affect the sound being produced by the clarinet.

Aside from factors mentioned earlier like how hard a reed is blown, its state or health and its strength, there are other factors that will affect the sound a clarinet produces.

Firstly, your embouchure will greatly affect the sound quality of a clarinet. Playing the clarinet with a closed throat or placing too much of your lower lip on the reed will produce a low-quality sound. When the right technique is used, the reed receives a perfect amount of pressure and the resulting sound will be of high quality. For a perfect clarinet embouchure, straighten your chin by placing your lower lip against your teeth, place the instrument’s mouthpiece on your lower lip, rest your teeth on top of the mouthpiece and then close your lips to trap air.

Also, the amount of air used during playing will affect the sound a clarinet produces. Despite the clarinet being a small instrument, it requires a lot of air to good quality sound. Sitting properly with your back straight and shoulders back will allow your lungs to accommodate more air needed to produce good sound. Be sure to blow from your stomach and not your throat as you play.

Conclusion

The sound produced by the clarinet is thanks to vibrations of the reed that cause a soundwave that is then projected by the instrument’s bell.

FAQs

What are a clarinet’s bell rings for?

Bell rings prevent the pressure of the tenon from splitting the bell apart.

What is the purpose of a register key?

The register key controls the clarinet’s pitch.