[alsa-devel] wrong decibel data?

[Raymond Yau]

2010/4/6 Nicolo' Chieffo <nicolo.chieffo at gmail.com>

> I've already attached my alsa-info.log in my first post.
>
>
> * alsamixer -3 dB (94%):
> Simple mixer control 'Master',0
>  Capabilities: pvolume pswitch pswitch-joined penum
>  Playback channels: Front Left - Front Right
>  Limits: Playback 0 - 65536
>  Mono:
>  Front Left: Playback 57079 [87%] [on]
>  Front Right: Playback 57079 [87%] [on]
>
> * alsamixer 0 dB (100%):
> Simple mixer control 'Master',0
>  Capabilities: pvolume pswitch pswitch-joined penum
>  Playback channels: Front Left - Front Right
>  Limits: Playback 0 - 65536
>  Mono:
>  Front Left: Playback 64044 [98%] [on]
>  Front Right: Playback 64044 [98%] [on]
>

you should notice that 0dB of Pulseaudio volume control is not at the
maximum dB
i.e. (  floating point 1.0 is not at 100% any more , seem that floating
point 0 (-inf dB) is also not at 0% point too )

http://thread.gmane.org/gmane.linux.alsa.devel/70545/focus=70585

>>   As mentioned for the PA case I decided to shift 0dB to max
amplification in any case, which I think is a workable way to avoid this
problem.


how about "dbmeasure pulse" and "dbmeasure hw:0,0" ?