High frequencies correspond to high tones, and low frequencies are low tones. Most audiograms go from around 250 hertz to 4000 hertz. Hearing losses over 20 decibels are considered abnormal. In the audiogram to the left, the red tracings are for the right ear, and the black tracings are for the left. The round circles represent the air conduction and the brackets are the bone conduction.
Low frequencies are to the left and high frequencies are on the right.
A normal audiogram would show all hearing loss of 20 dB or less. In this audiogram there is a sensorineural hearing loss on both sides in the high frequencies. In this audiogram the left side is normal. It could be caused by a problem with the tympanic membrane or the bones of the middle ear. The tympanogram is a test that measures how easily the eardrum vibrates back and forth and what pressure the vibration is the easiest.