Larynx

The larynx, or voice box, is the structure at the top of the windpipe that holds the vocal folds. It is built from cartilage, muscle and ligament, and it protects the airway as well as making sound.

Where you'll meet it

Everywhere on this site, because every voice operation works on some part of it and every training exercise moves it. Surgeons may call it the laryngeal framework when they mean the cartilage shell, as opposed to the soft folds inside.

What it is made of

The main pieces are the thyroid cartilage at the front (its forward edge is the Adam's apple), the ring-shaped cricoid cartilage below it, and two small cartilages at the back that swing the vocal folds open and closed. Muscles between these pieces change the length and tension of the folds; the cricothyroid muscle is the one most tied to pitch.

Its other jobs

The larynx is an airway valve first and a voice second. It closes when you swallow so food goes down the right way, and it holds your breath shut when you cough or lift something heavy. That is why voice surgery is done carefully and conservatively: an operation that made the voice higher but left the valve leaky, or narrowed the airway, would be a bad trade. It is also why the first days after some operations come with instructions about swallowing and coughing.

What a testosterone puberty does to it

It grows. The cartilage enlarges, the folds lengthen and thicken, and the larynx settles lower in the neck. That lengthens the space above it and lowers the voice's formants as well as its pitch. None of this reverses with oestrogen. The larynx does not respond to it, which is why trans women's voices do not change on hormones and why training, and sometimes surgery, is the route.

For trans men starting testosterone as adults, the cartilage has mostly stopped growing, so the change is mainly in the folds, which thicken. That is enough to lower most voices a long way, which is why surgery to lower pitch is rarely needed. It does less for resonance, because the larynx does not drop the way it does in a teenage puberty. The testosterone page covers the timeline.

How surgery changes it

In three different ways, which is worth keeping straight. Some operations work on the folds inside (glottoplasty). Some change the frame that holds them, tilting or cutting the cartilage to change tension or size (cricothyroid approximation, feminization laryngoplasty). And the tracheal shave only reshapes the outside of the thyroid cartilage, which changes how your neck looks and does nothing to the voice.

Larynx height in training

You can raise and lower the larynx with muscles in the neck, a little like the movement when you swallow. Holding it slightly higher shortens the space above it and brightens the sound. Learning to do that without strain is a core skill in feminization training.

The common misunderstanding is that higher is always better. Pushed too far, or held by squeezing the throat, it gives a tight, strained sound and a sore voice by evening. The aim is a position you can hold while relaxed, which is where a speech-language pathologist earns their fee. For masculinization the direction flips, and a slightly lower, relaxed larynx is part of darkening the sound.

← Back to the Glossary