2010/6/14 James Courtier-Dutton james.dutton@gmail.com
On 14 June 2010 10:54, Raymond Yau superquad.vortex2@gmail.com wrote:
2010/6/14 James Courtier-Dutton james.dutton@gmail.com
If you use "alsamixer", dB values are shown so it is easy to find the 0dB "sweet spot". I think it is pulse audio that hides this information when it combines two alsa mixer controls into one pulseaudio control.
The base volume seem to be the software 0dB point , (no software gain/atten), but the user want the hardware 0dB point (no hardware gain/atten if the hardware can provide hardware gain
This hardware 0dB point is extremely important when you want to record
using
line in and line out
alsamixer gives the hardware 0dB point.
you are right ,
For ac97 Base volume is the real hardware 0dB point of PCM volume, and Volume NORM is just the max_dB of +12dB which PA labeled it as 100% aka 0dB aka Volume NORM
For HDA , there is no yellow region because max_dB is 0dB , Base Volume and NORM is at the same point
http://en.wikipedia.org/wiki/Line_level
How can I get distortion free recording by line in of ac97 sound connected to line out of HDA onborad and vice versa ?
http://pulseaudio.org/wiki/WritingVolumeControlUIs#Colouredvolumesliders