dB SPL/HL Conversion
<charter> title = dB HL vs. dB SPL size = 800×330 align = center bgcolor = #ffffff type = line dots = 3 XAxisName = Frequency (Hz) YAxisName = Sound Level (dB) legendEntries = Hearing Level (HL), Sound Pressure Level (SPL) Free Field labelSerie = 3
15, 9, 3, -3, -4, 8 0, 0, 0, 0, 0, 0 250, 500, 1000, 2000, 4000, 8000 </charter>
The calculation is based on the frequency the measurement was taken at.
| Frequency (Hz) | dB HL | dB SPL FF |
|---|---|---|
| 250 | 0 | 15 |
| 500 | 0 | 9 |
| 1000 | 0 | 3 |
| 2000 | 0 | -3 |
| 4000 | 0 | -4 |
| 8000 | 0 | 8 |
SPL = Sound Pressure Level Free Field 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.
Examples
Audiogram dB HL vs. dB SPL
Audiogram using HL
Source: Wikipedia, http://en.wikipedia.org/wiki/File:Audio23.jpg
Target Curves using SPL
Source: ezFIT software