Figure 2. Relationship between sound pressure level and frequency for the right-hand headphone

From

Upper Frequency Limit of Hearing – A New Screening Method or an Illusion?

M. Bak, K. Rosniak-Bak

Journal of Biomedical Engineering and Technology. 2013, 1(3), 31-35 doi:10.12691/jbet-1-3-1