Explanation:

The SI unit of audio frequency is the hertz (Hz). It is the property of sound that most determines pitch. The generally accepted standard range of audible frequencies for humans is 20 to 20,000 Hz, although the range of frequencies individuals hear is greatly influenced by environmental factors. 20 to 20,000 Hz is generally accepted as the audible frequency range, this is the standard for most headphones. Some headphones offer wider ranges (for example, 5 to 33,000 Hz), but better frequency response does not always mean better sound quality.