19500 Hz
Treble (4–20 kHz) · D#10
Turn the volume down before you play. A pure tone is harder on the ears than music at the same level.
Mosquito tone
A high tone that fades with age. Most twenty-year-olds hear it; by forty, most people no longer do.
| Wavelength | 1.8 cm |
|---|---|
| Period | 51.3 µs |
| Nearest note | D#10 |
| Off by | -36 cents |
| Audible | Yes |
| Harmonics | 39000 Hz · 58500 Hz · 78000 Hz |
| One octave down | 9750 Hz |
| One octave up | 39000 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 19500 Hz sound like?
It is a pure tone vibrating 19500 times a second. It falls inside the range people hear, and the nearest musical note is D#10.
Q. What is the wavelength of 19500 Hz?
1.8 cm in air. Sound travels 343 metres per second through 20 °C air, so the wavelength is that distance divided by 19500.
Q. What note is 19500 Hz?
The nearest note is D#10, and it is 36 cents flat. A semitone is 100 cents, so that is about 36% of a semitone away.
Q. I cannot hear 19500 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 19500 Hz?
The whole-number multiples: 39000 Hz, 58500 Hz, 78000 Hz. An octave up is double, 39000 Hz; an octave down is half, 9750 Hz.
Nearby frequencies
Frequency doubles for every octave, so closeness is measured in ratios, not differences.