Hertz is a term used in audio to describe frequency or tone. It is also known as cycles per second and is abbreviated as Hz. A single Hertz is one wave cycle from crest to crest. Human hearing is sensitive to frequencies or tones ranging from 20 to 20,000 Hertz, or 20Hz to 20kHz. It is named after Heinrich Hertz, a German physicist. The term kHz means kiloHertz (thousands of Hertz) and mHz means megaHertz (millions of Hertz).
Examples: The electricity of an AC wall outlet is said to have a frequency of 60 Hertz as it cycles negative then positive 60 times each second. Sound is an oscillating wave, but it has a broad range of frequencies. A low-frequency sound (say 50 Hz) might sound like a low rumble, while a high frequency sound (say 12,000 Hz), might sound more like a “sizzle”. A person with normal hearing can hear up to about 20,000 Hz.
When puppies are born, they do not hear until around the 21st day of life. When their hearing develops, dogs are more attuned to high frequency sounds (beyond 12,000Hz) and also very faint sounds, than are humans. The approximate range of hearing for dogs is 64hz-45,000Hz. A typical dog whistle frequency ranges from 16kHz-22kHz. Many dogs bark at vacuum cleaners because they can hear a high-pitched sound in the motor that humans do not hear.
Dogs with ears that stand up generally hear better than dogs that have floppy ears, especially when the perked ears can rotate in the direction of the sounds they hear. Also, dogs do lose their hearing as they age, much the same as humans do.
Keeping your dog healthy and doing your best to protect him from sudden sharp and loud noises will help preserve their keen sense of hearing.
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