Semitone

A semitone is one step on a piano keyboard, from any key to the very next one, black or white. Twelve of them make an octave, and each one is a rise of about 6 per cent in frequency, which is why they track what the ear hears better than hertz do.

Where you'll meet it

In surgical results, on surgeon websites and in papers ("a mean rise of N semitones"), and in training apps that show your pitch against a keyboard. A therapist may also use semitones to set targets, because "three steps up from where you are now" means something to anyone who has sat at a piano.

Why not just use hertz

Because the ear hears ratios, not differences. Rising from 100 to 120 Hz is about three semitones; rising from 200 to 220 Hz is under two. A semitone is the same size to the ear wherever it sits, so it lets you compare a rise in a low voice with a rise in a higher one on equal terms. Surgeons who report carefully give both numbers.

What some rises look like

As a rough illustration, starting from a speaking pitch of about 110 Hz:

• 3 semitones up is roughly 131 Hz
• 5 semitones up is roughly 147 Hz
• 7 semitones up is roughly 165 Hz
• 12 semitones, a full octave, is 220 Hz

Those are arithmetic, not outcomes. They show what a reported number would mean for a voice starting at that point; they say nothing about what any operation will do for you.

How it's measured

A fundamental frequency reading is taken before and after, and the gap between them is converted to semitones. The catch is what you are asked to do while the reading is taken. A held "eee" is steady and easy to measure. Reading a set passage is closer to real speech. Free conversation is the most honest and the hardest to pin down, because pitch moves constantly with intonation. The same voice can give noticeably different averages across the three.

What it means for you

If you are training, semitones are the more useful unit for tracking yourself. Your target is a distance from your own starting point, not a hertz figure someone else posted, and one or two semitones of steady progress is a real change you will hear on a recording.

If you are weighing surgery, ask the surgeon for their typical rise in semitones, measured in conversation, at a year or later. That one sentence covers the three ways a number can flatter itself.

Common misunderstandings

A bigger number is not automatically a better result. A voice raised a long way with a heavy vocal weight and unchanged resonance can still read as male. A smaller rise on a voice already trained often sounds more natural.

An average is not a promise. "A mean rise of several semitones" hides a spread: some people gain more, some much less. Ask what the lower end looked like and what happened to those patients.

Pitch is not the whole voice. A semitone figure describes pitch only. It also hides timing: a result at three months, while the folds are still settling, may not survive to a year. The blog post on semitones goes through how to read the numbers you will be shown.

Related decisions

Where your pitch sits after surgery or training also depends on your pitch floor, the lowest note you can reach, which some operations deliberately raise. That matters as much as the average for anyone who wants to stop dropping back into their old voice when tired or laughing.

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