In: Physics
What dB level corresponds to a 500 Hz tone that is perceived to be at 40 phons?
The lines on the graph in Figure 1 are referred to as equal loudness curves; each line is representative of a specific phon rating. The coordinate axes are the decibel rating and the frequency. To determine the dB rating of a sound with a given frequency and phon rating, one must first locate the point on the graph with the given phon rating where cut the 500h HZ axis...
from graph the the dB level greater than 40dB and near to 45 dB