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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) 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
250 0 15
500 0 9
1000 0 3
2000 0 -3
4000 0 -4
8000 0 8

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.

Examples

Audiogram dB HL vs. dB SPL

Audiogram using dB HL vs. dB SPL

Audiogram using HL

Audiogram using HL. Source: Wikipedia, http://en.wikipedia.org/wiki/File:Audio23.jpg

Source: Wikipedia, http://en.wikipedia.org/wiki/File:Audio23.jpg


Sample Audiogram using HL

Source: ezFIT software


Target Curves using SPL

Sample Target Curves (thick dotted lines) and related Response Curves (thin continuous lines)

Source: ezFIT software