pydsm.iso226.iso226_spl_contour

pydsm.iso226.iso226_spl_contour(L_N=40, hfe=False)

Generates an equal loudness contour as described in ISO 226.

This function returns the control points describing the equal loudness contour for the input phon level, according to ISO 226 sect 4.1.

Parameters:

L_N : float, optional

perceived loudness level in phons.

hfe : bool

whether the table should be augmented with a data point at 20 kHz (High-Frequency-Enhanced table)

Returns:

f : ndarray

frequencies where the loudness is evaluated.

spl : ndarray

equivalent sound pressure level at the frequencies f.

Notes

1 phon is 1 dB_SPL (sound pressure level) at 1 kHz. Sound pressure levels are measured in dBs by referring to a reference pressure level P0 (close to the hearing threshold at 1 kHz and set to 20 uPa RMS).

The valid input phon range is 0-90 dB_SPL. Above 80 dB, only the frequency range 20-4000 Hz is significant.