Dynamic range soundcard tablet

[SaraMagits]

For the APEX audiometry experiment on tablet, there seems to be a problem with the dynamic range of the tablet. This results in the softest sounds (20dB to -10dB) to be played at the same loudness, no audible difference.

Calculating dynamic range: wav file + calib = 80dB, then recalculate to lower intensities

[tomfrancart]

This is probably due to the sound card being used in 16 bit mode (portaudio has a similar issue on windows)
If possible we should change this to 24bit

[tomfrancart]

https://github.com/Gundersanne/portaudio_opensles/blob/master/src/hostapi/opensles/pa_opensles.c
Line 163 and 195 and 787 might be a good place to start looking

[tomfrancart]

https://android.googlesource.com/platform/frameworks/wilhelm/+/72721a95943c68ea0d75eb5c1ff2ab7380e4dc6f/src/android/android_sles_conversions.h