24000 Hz
Ultrasound (above 20 kHz) · F#10
Turn the volume down before you play. A pure tone is harder on the ears than music at the same level.
Ultrasound
Above the human hearing range, so you will not hear it. Devices and animals may still respond.
| Wavelength | 1.4 cm |
|---|---|
| Period | 41.7 µs |
| Nearest note | F#10 |
| Off by | +23 cents |
| Audible | No |
| Harmonics | 48000 Hz · 72000 Hz · 96000 Hz |
| One octave down | 12000 Hz |
| One octave up | 48000 Hz |
How to read this
- Hertz counts how many times the air vibrates per second. The bigger the number, the higher the pitch.
- Wavelength is the speed of sound (343 m/s at 20 °C) divided by the frequency. That makes 20 Hz seventeen metres long and 20 kHz under two centimetres.
- People hear roughly 20 Hz to 20 kHz, but the upper limit drops with age. Past about 15 kHz, some hear the tone and some do not.
- Hearing nothing does not mean the equipment is broken. Small speakers cannot reach the low notes, and for the high ones it is the ear that gives up first.
Frequently asked questions
Q. What does 24000 Hz sound like?
It is a pure tone vibrating 24000 times a second. It sits outside the usual human range of 20 Hz to 20 kHz, so most people will hear nothing.
Q. What is the wavelength of 24000 Hz?
1.4 cm in air. Sound travels 343 metres per second through 20 °C air, so the wavelength is that distance divided by 24000.
Q. What note is 24000 Hz?
The nearest note is F#10, and it is 23 cents sharp. A semitone is 100 cents, so that is about 23% of a semitone away.
Q. I cannot hear 24000 Hz — is something wrong?
High tones are the first to go with age. Most twenty-year-olds hear this pitch; past forty, many people no longer do.
Q. What are the harmonics of 24000 Hz?
The whole-number multiples: 48000 Hz, 72000 Hz, 96000 Hz. An octave up is double, 48000 Hz; an octave down is half, 12000 Hz.
Nearby frequencies
Frequency doubles for every octave, so closeness is measured in ratios, not differences.