[alsa-devel] Low volume ad1983

[Takashi Iwai]

At Thu, 13 Mar 2014 21:20:46 +0800,
Raymond Yau wrote:
> 
> >>sam chan wrote:
> >> i'm having a problem with sound volume being too low.
> >> i **think** it's due to the levels of my channel map being
> >> too low.....
> 
> >The channel map specifies which channel goes to which
> >physical output.
> 
> >> my alsa-info...
> >> http://www.alsa-project.org/db/?f=3ba6278df3c6c4abe5196ad37f8015de7223ca8e
> 
> >> Simple mixer control 'Master',0
> >>   Mono: Playback 37 [59%] [-39.00dB] [on]
> 
> >That is pretty low.
> 
> >> Simple mixer control 'Loopback Mixing',0
> >>   Item0: 'Enabled'
> 
> >Why is this enabled?
> 
> seem driver bug

Not really.

> 1) Should the volume control and playback switch of line out be named
> as Front instead of PCM ?

Depends.  For multi-channel setup, we take "Front", but in other
cases, it may become "PCM".  It's suboptimal, indeed, and we need a
better naming rule for the shared volume control.

> 
> 
> Node 0x05 [Pin Complex] wcaps 0x400185: Stereo Amp-Out
>   Control: name="PCM Playback Volume", index=0, device=0
>     ControlAmp: chs=3, dir=Out, idx=0, ofs=0
>   Control: name="PCM Playback Switch", index=0, device=0
>     ControlAmp: chs=3, dir=Out, idx=0, ofs=0
>   Control: name="Line Out Jack", index=0, device=0
>   Amp-Out caps: ofs=0x3d, nsteps=0x3f, stepsize=0x05, mute=1
>   Amp-Out vals:  [0x23 0x23]
>   Pincap 0x00000017: OUT Detect Trigger ImpSense
>   Pin Default 0x01014010: [Jack] Line Out at Ext Rear
>     Conn = 1/8, Color = Green
>     DefAssociation = 0x1, Sequence = 0x0
> 
> 2) dB max of virtual master playback volume is different from the
> slave when slave dbmax of slaves  > 0

It's the designed behavior.  The Master volume is an offset applied to
the slave value, thus it's always up to 0dB.  The lowest value is
somewhat bogus, but it's anyway cut off under 0.



Takashi

> 
> 
> 	control.1 {
> 		iface MIXER
> 		name 'PCM Playback Volume'
> 		value.0 61
> 		value.1 61
> 		comment {
> 			access 'read write'
> 			type INTEGER
> 			count 2
> 			range '0 - 63'
> 			dbmin -9150
> 			dbmax 300
> 			dbvalue.0 0
> 			dbvalue.1 0
> 		}
> 	}
> 	control.3 {
> 		iface MIXER
> 		name 'Headphone Playback Volume'
> 		value.0 61
> 		value.1 61
> 		comment {
> 			access 'read write'
> 			type INTEGER
> 			count 2
> 			range '0 - 63'
> 			dbmin -9150
> 			dbmax 300
> 			dbvalue.0 0
> 			dbvalue.1 0
> 		}
> 	}
> 	control.5 {
> 		iface MIXER
> 		name 'Speaker Playback Volume'
> 		value 61
> 		comment {
> 			access 'read write'
> 			type INTEGER
> 			count 1
> 			range '0 - 63'
> 			dbmin -9150
> 			dbmax 300
> 			dbvalue.0 0
> 		}
> 	}
> 	control.17 {
> 		iface MIXER
> 		name 'Master Playback Volume'
> 		value 37
> 		comment {
> 			access 'read write'
> 			type INTEGER
> 			count 1
> 			range '0 - 63'
> 			dbmin -9450
> 			dbmax 0
> 			dbvalue.0 -3900
> 		}
> 	}