For masking with insert earphones, what is the necessary dB difference?

When conducting auditory masking with insert earphones, a necessary dB difference refers to the level of sound that must be presented to the non-test ear to effectively prevent any auditory crossover that may impact the test results. A 60 dB difference is essential because it ensures that the masking noise is sufficiently loud to raise the threshold of hearing in the non-test ear, allowing for accurate assessment of the hearing threshold in the test ear.

This dB difference is based on the principles of psychoacoustics, specifically addressing the effective masking required to compensate for interaural attenuation. The 60 dB level is significant enough to mask the low-level sounds that may leak from the test ear to the non-test ear, ensuring that the results accurately reflect the hearing ability of the individual being tested.

In audiometry, utilizing the correct amount of masking is critical for differential diagnosis and ensuring that results are valid and reliable, as auditory crossover can falsely indicate better hearing in one ear or mask the true hearing capabilities of the test ear. Thus, understanding the necessity for this specific dB difference is crucial when performing audiometric evaluations with insert earphones.