sorry if I don't post at the right place or if this issue has already been discussed elsewhere:
While measuring Rasp2 analog output THD+N at various frequencies, I played a little with the AudioPrecision I'm blessed to have at work.
I tested HDMI out to check the audio quality, which is supposed to be pristine unless jitter or clipping occurs.
Using -3dBFS wav file from a USB key, I found out the "100" audio setting was awfully clipped and had a few % THN+N score (so I guessed) while "99" setting and below were OK (ultra low THD+N)
- clipping_HDMI_small.jpg (80.38 KiB) Viewed 1444 times
- no_clipping_HDMI_small.jpg (70.28 KiB) Viewed 1444 times
Test condition:
beta-20141216 on a Rasp2 playing a -3dBFS wav sine
From now on I'll pay attention when setting my audio configuration.
Has anybody an idea about what happens when @100%, maybe a clipping in the SW decoding before HDMI encapsulation?
Best regards
Stephane
