[alsa-devel] Mixer volume/decibel mapping

Raymond Yau superquad.vortex2 at gmail.com
Wed May 26 01:24:51 CEST 2010

2010/5/25 James Courtier-Dutton <james.dutton at gmail.com>

> Could this maybe explain why pulseaudio was having such problems with
> alsa with regards to gain controls????

I don't think so since no soc user report wrong dB range


If the flat volume model of PA is  0% to 150% , this mean that alsa-lib does
not provide any DB scale suitable for PA to implement dB info for the pulse
device as DB_LINEAR require max is 0dB ( at least capture stream must have
gain )

only one of the PA developer complain about his HDA codec has incorrect dB
range but not willing to provide alsa-info.sh

There is a patch which may affect the dB scale


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