maad.spl.amplitude2dBSPL

maad.spl.amplitude2dBSPL(s, gain, Vadc=2, sensitivity=-35, dBref=94, pRef=2e-05)[source]

Convert signal (amplitude) to instantaneous sound pressure level (L [dB SPL]).

Parameters:

sndarray-like or scalar: s is an amplitude signal (not energy signal : s² )
gaininteger: Total gain applied to the sound (preamplifer + amplifier)
Vadcscalar, optional, default is 2Vpp (=>+/-1V): Maximal voltage (peak to peak) converted by the analog to digital convertor ADC
sensitivityfloat, optional, default is -35 (dB/V): Sensitivity of the microphone
dBrefinteger, optional, default is 94 (dBSPL): Pressure sound level used for the calibration of the microphone (usually 94dB, sometimes 114dB)
pRefSound pressure reference in the medium (air:20e-6 Pa, water:1e-6 Pa)

Returns:

Lndarray-like or scalar: ndarray-like or scalar containing the sound waveform in dB SPL (Sound Pressure level in dB)

See also

power2dBSPL

Examples

>>> import numpy as np
>>> w, fs = maad.sound.load('../data/cold_forest_daylight.wav') 
>>> Sxx_amplitude,tn,fn,_ = maad.sound.spectrogram (w, fs, nperseg=1024, mode='amplitude')  
>>> S_amplitude_mean = np.mean(Sxx_amplitude, axis=1)

Get instantaneous sound pressure level (L).

>>> maad.spl.amplitude2dBSPL(S_amplitude_mean, gain=42)    
array([39.56422048, 44.37117437, 41.95705677, 39.60547011, 36.43237323,
       33.24966066, 31.44139953, 30.4473799 , 28.91589639, 27.26962076,
       26.7722199 , 26.27328293, 25.69373328, 24.73880674, 23.85828781,
       ...
       -6.30767022, -6.46481481, -6.49907112, -6.52754376, -6.52476444,
       -6.73617834, -6.75685948])