Calibrates attenuators such that a full amplitude sine wave is put out at an sound pressure level as requested by setIntensity(). The sound pressure level is based on the root mean square of the sound waveform!
Options
frequencyrange=2000..20000..500: Frequency range (Hz) (string)
intmin=45dB SPL: Minimum sound intensity (number)
intrange=35dB SPL: Sound intensity range (number)
intstep=5dB SPL: Sound intensity step (number)
outtrace=Left-Speaker: Output trace (string)
intrace=Sound-1: Input trace (string)
reset=false: Reset calibration for each frequency? (boolean)
clear=false: Clear calibration table? (boolean)
duration=80ms: Duration of stimulus (number)
skip=20ms: Initial time to skip for analysis (number)
win=1ms: Window for computing rms response (number)
fitslope=false: Fit slope in addition to offset (boolean)
ramp=1ms: Ramp time of stimulus (number)
pause=0ms: Pause between stimuli (number)
scale=3.16: Scale for V/Pa (number)
Files
calibspeakers-intensities.dat : the calibration data (measured versus requested stimulus intensity).
calibspeakers-offsets.dat : the calibration data (measured versus requested stimulus intensity).
Plots
The plot shows the measured versus the requested stimulus intensity (red circles). The yellow line is a fit of a straight line to the data. This line should for a successful calibration coincide with the blue 1:1 line.
Requirements
The LoadSpeaker Attenuate class associated with output trace Speaker-Left or Speaker-Right
Repeatedly play a signal with an triangular amplitude modulation and average the voltage output of a microphone. The averaged sound is then plotted as a function of distance the sound must have travelled. This way echos can be inspected.
Options
duration=10ms: Stimulus duration (number)
frequency=0kHz: Carrier frequency (number)
intensity=80dB: Stimulus intensity (number)
repeats=0: Repetitions of stimulus (integer)
pause=100ms: Duration of pause between stimuli (number)
outtrace=Left-Speaker: Output trace (string)
intrace=Sound-1: Input trace (string)
average=10: Number of trials to be averages (integer)
maxecho=10m: Maximum echo distance (number)
soundspeed=343m/s: Speed of sound (number)
Plot
The plot shows the averaged sound (orange) recorded by the microphone as a function of distance the sound must have travelled. The x-axis is shifted such that the peak of the triangular sound pulse indicates the distances. Without any delays the peak amplitude of the recorded sound will sit at distance zero (not the beginning of the sound pulse).
For orientation the original sound pulse is plotted in yellow at the position of the largest peak.
Converts intensities givenen in dB SPL to attenuation level in dependence on carrier frequency.
Author
Jan Benda
Version
1.4 (Jul 5, 2017)
Calibration
The conversion is set by the CalibSpeaker RePro which defines stimulus intensity as dB SPL, i.e. root-mean-square amplitude of a full-amplitude sine wave.
The calibration table is saved in the files calibD-C.dat where D is the device number of the data acquisition board and C is the analog output channel of that board.
Options
line: the line on the attenuator
aodevice: the identifier analog output device
aochannel: the channel of the analog output device
maxvoltage: maximum allowed peak voltage to be put out by the attenuator.
