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dB SPL/HL Conversion
The calculation is based on the frequency the measurement was taken at.
| Frequency (Hz) | dB SPL | dB HL |
|---|---|---|
| 250 | 15 | 0 |
| 500 | 9 | 0 |
| 1000 | 3 | 0 |
| 2000 | -3 | 0 |
| 4000 | -4 | 0 |
| 8000 | 8 | 0 |
SPL = Sound Pressure Level HL = Hearing Level
HL is used for Audiogram representation. SPL is used for Target Curves representation. The HL chart has the Y-axis origin at the top left corner. The SPL chart has the Y-axis origin at the bottom left corner.
Audiogram using HL
Source: Wikipedia, http://en.wikipedia.org/wiki/File:Audio23.jpg
Source: ezFIT software
Target Curves using SPL
Source: ezFIT software