pydsm.iso226.iso226_spl_itpl¶
- pydsm.iso226.iso226_spl_itpl(L_N=40, hfe=False, k=3)¶
Generates an interpolation of an equal loudness contour.
This function returns an interpolation object 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)
k : int
interpolation order
Returns: itpl : univariate interpolation object
function-like object that takes a frequency f as its input and returns the equivalent sound pressure level at 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.