An audio frequency generator is an electronic device that is used to create sound waveforms at different frequencies. An audio generator is capable of creating sound frequencies across a broad spectrum and is sometimes used to test a person's hearing range.

The frequency of a sound wave is measured using a unit called Hertz (Hz). Frequency measures the number of cycles a waveform makes in a second. One hertz represents one cycle per second. The typical hearing range for humans is between 20 and 20,000 Hz. This range gradually decreases as a person ages or experiences ear damage. The sound frequency range divides into the sub-audio rate, audio rate and ultrasonic rate. Anything below 20 Hz is sub-audio, while anything above 20,000 Hz is considered ultrasonic. The average hearing range for humans falls within the audio rate.

An audio frequency can generate frequencies in the sub-audio rate, audio rate and the ultrasonic rate. An audio generator can also create different sound waveforms such as sine waves, square waves and triangle waves. Most generators also have a setting to increase or decrease the intensity of the sound output in order to test the hearing sensitivity of a person taking a hearing test.