Start with your device volume low. Very low tones may be inaudible on phone or laptop speakers; very high tones can be uncomfortable on headphones.
What does 20 Hz sound like?
20 Hz is a sub-bass frequency. It is a very deep sub-bass tone that you feel in your chest as much as hear. Small speakers struggle to reproduce it; good headphones or a subwoofer will.
A 20 Hz sound wave completes 20 cycles every second, so one cycle lasts 50 ms. In air at 20 °C, where sound travels at about 343 m/s, each wave is 17.15 m (56.27 ft) long; in water it stretches to 74.05 m because sound moves about 4.3 times faster there.
Musically, 20 Hz is 49 cents above D♯0 (19.45 Hz) in standard A440 tuning. Doubling it to 40 Hz raises the pitch by one octave; halving it to 10 Hz lowers it by one.
Wavelength of 20 Hz in different materials
| Medium | Speed of sound | Wavelength |
|---|---|---|
| Air (20 °C) | 343 m/s | 17.15 m |
| Fresh water | 1,481 m/s | 74.05 m |
| Seawater | 1,500 m/s | 75.00 m |
| Helium | 1,007 m/s | 50.35 m |
| Steel | 5,960 m/s | 298.00 m |
| Glass | 5,640 m/s | 282.00 m |
Harmonics and octaves
Real instruments playing 20 Hz also produce harmonics at whole-number multiples of the fundamental. Their relative strength gives each instrument its timbre.
Which animals can hear 20 Hz?
Cannot hear it
Dogs, Cats, Horses, Cows, Sheep, Pigs, Goats, Rabbits, Rats, Mice, Gerbils, Guinea pigs, Hedgehogs, Raccoons, Opossums, Chinchillas, Bats, Beluga whales, Bottlenose dolphins, Chickens, Canaries, Budgerigars (parakeets), Cockatiels, Owls, Bullfrogs, Tree frogs, Catfish, Tuna, Greater wax moths
Frequently asked questions
What does 20 Hz sound like?
It is a very deep sub-bass tone that you feel in your chest as much as hear. Small speakers struggle to reproduce it; good headphones or a subwoofer will.
Can humans hear 20 Hz?
Yes. 20 Hz is inside the typical human hearing range of 20 Hz to 20 kHz.
What musical note is 20 Hz?
20 Hz is 49 cents above D♯0, which is 19.45 Hz in standard A440 tuning.
What is the wavelength of 20 Hz?
About 17.15 m in air at 20 °C and 74.05 m in water.
Can dogs hear 20 Hz?
No – dogs hear roughly 67 Hz to 45,000 Hz.