[alsa-devel] wrong decibel data?

[Raymond Yau]

2010/6/14 Colin Guthrie <gmane at colin.guthr.ie>

> 'Twas brillig, and Raymond Yau at 14/06/10 01:25 did gyre and gimble:
> > if your sound card have ac97 codec ., you can use audacity to record the
> > output from hw:0,0 and you will see clipping occur when you set "PCM"
> volume
> > above 0dB
>
> So the standard response is "don't do that then" :)
>
> That's why the base volume is shown to the user via GUIs so that they
> can gauge the best point on the slider to use. Currently there is no
> indication with alsa sliders at which point the 0dB "sweet spot" lies.
>
> IMO this is a good improvement for usability.
>
> Col
>


The correct way is to provide the real ALSA 's 0dB point (Playback volume)
for the user of AC97 sound card so that they can record without any
distortion using line in with the loopback cable connected to line out.