Pure Tone Audiometry is one of the basic hearing tests performed by hearing health professionals or hearing specialists.  There are 2 types of Pure tone Audiometry.  Sounds or tones that are presented to the ear (outer and middle ear) through an earphone are called an Air Conduction Test.  Each side of the ear is tested separately.  This test assists the hearing care specialist or audiologist to determine the softest sound a person can hear at varying frequencies and pitches.   Another type of Pure tone Audiometry is a Bone Conduction Test wherein a small device or an oscillator is placed behind the patient’s ear or the mastoid bone.  The device produces sounds directly to the cochlea.