Comment # 5 on bug 1172412 from Takashi Iwai

(In reply to Takashi Iwai from comment #4)
> Well, my question was to compare the actual loudness you hear from both
> USB-audio and onboard sounds.  For example, try to set "Speaker Playback
> Volume" to the raw value 10 (of 31) on Kingston, and compare the loudness of
> the output from onboard audio.  Increase / decrease the onboard audio, and
> find the same loudness as Kingston, then read the dB value shown on the
> onboard audio.  That's the value to be used for Kingston device, too.
> 
> For checking the onboard audio dB value, the best is to like below:
> - Assume you test from the line out.  The corresponding output volume is
> "Front Playback volume", and set this to 100% (0dB):
>   % amixer -c1 cset name="Front Playback Volume" 64,64
> 
> - Change Master volume via amixer, e.g. raw value 30:
>   % amixer -c1 cset name="Master Playback Volume" 30,30
> 
>   Then compare the loudness.

Oh, I forgot here the important step:
- To compare the loudness, use native aplay, e.g.

  % pasuspender -- aplay -Dplughw:1 -vv foo.wav