What's the basic anatomy of your vocal cords?

1 Vocal cords and larynx

Your vocal cords are two thin, flexible bands of tissue that stretch across your larynx, or voice box. The larynx is a cartilaginous structure that sits on top of your trachea, or windpipe. The larynx has several functions, such as protecting your airway, swallowing, coughing, and producing sound. The vocal cords are attached to the front and back of the larynx, and they can open and close to regulate the flow of air from your lungs.

2 Vocal folds and glottis

Your vocal cords are also called vocal folds, because they can fold together or apart. When you breathe, your vocal folds are apart, creating a wide space between them called the glottis. This allows air to pass freely through your larynx. When you speak or sing, your vocal folds come together, narrowing or closing the glottis. This creates resistance to the air flow, causing the vocal folds to vibrate. The vibration of the vocal folds produces sound waves that travel through your throat, mouth, and nose.

3 Pitch and frequency

The pitch of your voice is determined by the frequency of the sound waves that your vocal folds produce. Frequency is measured in hertz (Hz), which is the number of cycles per second. The higher the frequency, the higher the pitch. The lower the frequency, the lower the pitch. The frequency of your vocal folds depends on their length, tension, and mass. When you sing higher notes, your vocal folds stretch, tighten, and thin. This increases their frequency. When you sing lower notes, your vocal folds relax, shorten, and thicken. This decreases their frequency.

4 Volume and amplitude

The volume of your voice is determined by the amplitude of the sound waves that your vocal folds produce. Amplitude is measured in decibels (dB), which is the intensity or loudness of sound. The higher the amplitude, the louder the volume. The lower the amplitude, the softer the volume. The amplitude of your vocal folds depends on the amount of air pressure that you use to push them together. When you sing louder, you use more air pressure, creating stronger vibrations and larger sound waves. When you sing softer, you use less air pressure, creating weaker vibrations and smaller sound waves.

5 Quality and timbre

The quality of your voice is determined by the timbre of the sound waves that your vocal folds produce. Timbre is the characteristic or color of sound that distinguishes it from other sounds of the same pitch and volume. Timbre is influenced by many factors, such as the shape and size of your vocal tract, the resonance of your chest, throat, mouth, and nose, the articulation of your tongue, lips, and teeth, and the expression of your emotions. When you sing, you can modify your timbre by changing the position of your jaw, tongue, soft palate, and larynx, as well as by adding vibrato, breathiness, or other effects.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?