Which transducer has the highest inter-aural attenuation for air conduction (AC)?

The choice of inserts as the transducer with the highest inter-aural attenuation for air conduction is based on the design and functionality of these earphones. Inserts, or insert earphones, fit deep into the ear canal, creating a better seal and reducing sound leakage between the ears. This improved acoustic isolation minimizes the impact of sounds being transmitted from one ear to the other through the skull and surrounding tissues, which is essential for accurate audiometric testing.

The high inter-aural attenuation provided by inserts allows for a more precise assessment of hearing thresholds, especially in cases where there may be a significant difference in hearing sensitivity between the ears. This characteristic makes inserts particularly useful in audiology, as they help in reducing cross-hearing and improving the reliability of test results.

In contrast, bone oscillators and supra-aural headphones typically provide lower inter-aural attenuation. Bone oscillators vibrate the bones of the skull directly and can transmit sound to both ears, making it challenging to isolate responses. Supra-aural headphones sit on the outer ear and can allow for more sound leakage between ears because of their placement, again compromising inter-aural attenuation. Hence, insert earphones are clearly distinguished for their superior performance regarding inter-aural attenuation