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What does 685 Hz sound like?
685 Hz is a midrange frequency. It is a clear midrange tone, close to where the human ear does most of its work for speech and melody.
A 685 Hz sound wave completes 685 cycles every second, so one cycle lasts 1.46 ms. In air at 20 °C, where sound travels at about 343 m/s, each wave is 50.1 cm (1.64 ft) long; in water it stretches to 2.16 m because sound moves about 4.3 times faster there.
Musically, 685 Hz is 34 cents below F5 (698.46 Hz) in standard A440 tuning. Doubling it to 1,370 Hz raises the pitch by one octave; halving it to 342.5 Hz lowers it by one.
Wavelength of 685 Hz in different materials
| Medium | Speed of sound | Wavelength |
|---|---|---|
| Air (20 °C) | 343 m/s | 50.1 cm |
| Fresh water | 1,481 m/s | 2.16 m |
| Seawater | 1,500 m/s | 2.19 m |
| Helium | 1,007 m/s | 1.47 m |
| Steel | 5,960 m/s | 8.70 m |
| Glass | 5,640 m/s | 8.23 m |
Harmonics and octaves
Real instruments playing 685 Hz also produce harmonics at whole-number multiples of the fundamental. Their relative strength gives each instrument its timbre.
| Harmonic | Frequency | Nearest note |
|---|---|---|
| 1× (fundamental) | 685 Hz | F5 |
| 2× | 1.37 kHz | F6 |
| 3× | 2.055 kHz | C7 |
| 4× | 2.74 kHz | F7 |
| 5× | 3.425 kHz | A7 |
| 6× | 4.11 kHz | C8 |
| 7× | 4.795 kHz | D8 |
| 8× | 5.48 kHz | F8 |
Which animals can hear 685 Hz?
Can hear it
Humans, Dogs, Cats, Horses, Cows, Sheep, Pigs, Goats, Rabbits, Rats, Gerbils, Guinea pigs, Hedgehogs, Raccoons, Ferrets, Opossums, Chinchillas, Elephants, Bottlenose dolphins, Chickens, Canaries, Budgerigars (parakeets), Cockatiels, Owls, Bullfrogs, Tree frogs, Goldfish, Catfish, Tuna
Cannot hear it
Instruments and voices that can play 685 Hz
Frequently asked questions
What does 685 Hz sound like?
It is a clear midrange tone, close to where the human ear does most of its work for speech and melody.
Can humans hear 685 Hz?
Yes. 685 Hz is inside the typical human hearing range of 20 Hz to 20 kHz.
What musical note is 685 Hz?
685 Hz is 34 cents below F5, which is 698.46 Hz in standard A440 tuning.
What is the wavelength of 685 Hz?
About 50.1 cm in air at 20 °C and 2.16 m in water.
Can dogs hear 685 Hz?
Yes – dogs hear roughly 67 Hz to 45,000 Hz.