HDA Conexant: is mic boost possible?

HDA Conexant: is mic boost possible?

[Pablo N. Hess]

I have to make the sound chip of a Itautec W7635 (= FIC VA250D) work on 
a Gentoo(-based) distro (I'm now trying Sabayon).
It is a HDA-intel (Conexant codec).

Using my earphones as a stereo mic, recording with 'arecord -f cd' has 
always worked perfectly fine, from alsa-driver-1.0.14 on.

However, when using a regular mono mic (like the ones that come in 
common headsets), recording simply does *not* work.

Here's the quick info:

alsa-driver-1.0.14:
   playback: ok
   recording:
     stereo mic: ok
     mono mic: no input at all (very high volume already tried)

alsa-driver-1.0.15rc1:
   playback: ok (even better than with alsa-driver-1.0.14)
   recording:
     stereo mic: ok (seems better thatn with alsa-driver-1.0.14)
     mono mic: *very* very low volume, bad quality, lots of low-volume 
noise, too.


Now the paragraphed info:

Playback is perfectly ok since alsa-driver-1.0.14, just like recording 
with an earphone as a stereo mic.

With alsa-driver-1.0.14, definitely no mono-mic input works, no matter 
the settings at alsamixer.
With alsa-driver-1.0.15rc1, mono-mic input works very very bad 
(extremely low volume, terrible quality, lots of clicks and noise).

I guess that the mono mic needs a mic boost in alsa-driver-1.0.15rc1. 
However, with a 'grep -i "mic boost" .../pci/hda/*.c' 
(alsa-driver-1.0.15rc1 source code), it seems that only patch-realtek.c 
and patch-analog.c support this feature.

Is it even possible to add a mic boost feature to this codec?

The output of alsa-info.sh with alsa-driver-1.0.15rc1 is at:
http://pastebin.ca/681023

Thanks a lot for any info, and congratulations to all of you for your 
terrific work with ALSA.

Pablo Hess

Re: HDA Conexant: is mic boost possible?

[Tobin Davis]

I believe mic boost is on by default.  What model are you running this
as?  Laptop or Fujitsu?

Tobin

On Tue, 2007-09-04 at 11:14 -0300, Pablo N. Hess wrote:

> I have to make the sound chip of a Itautec W7635 (= FIC VA250D) work on 
> a Gentoo(-based) distro (I'm now trying Sabayon).
> It is a HDA-intel (Conexant codec).
> 
> Using my earphones as a stereo mic, recording with 'arecord -f cd' has 
> always worked perfectly fine, from alsa-driver-1.0.14 on.
> 
> However, when using a regular mono mic (like the ones that come in 
> common headsets), recording simply does *not* work.
> 
> Here's the quick info:
> 
> alsa-driver-1.0.14:
>    playback: ok
>    recording:
>      stereo mic: ok
>      mono mic: no input at all (very high volume already tried)
> 
> alsa-driver-1.0.15rc1:
>    playback: ok (even better than with alsa-driver-1.0.14)
>    recording:
>      stereo mic: ok (seems better thatn with alsa-driver-1.0.14)
>      mono mic: *very* very low volume, bad quality, lots of low-volume 
> noise, too.
> 
> 
> Now the paragraphed info:
> 
> Playback is perfectly ok since alsa-driver-1.0.14, just like recording 
> with an earphone as a stereo mic.
> 
> With alsa-driver-1.0.14, definitely no mono-mic input works, no matter 
> the settings at alsamixer.
> With alsa-driver-1.0.15rc1, mono-mic input works very very bad 
> (extremely low volume, terrible quality, lots of clicks and noise).
> 
> I guess that the mono mic needs a mic boost in alsa-driver-1.0.15rc1. 
> However, with a 'grep -i "mic boost" .../pci/hda/*.c' 
> (alsa-driver-1.0.15rc1 source code), it seems that only patch-realtek.c 
> and patch-analog.c support this feature.
> 
> Is it even possible to add a mic boost feature to this codec?
> 
> The output of alsa-info.sh with alsa-driver-1.0.15rc1 is at:
> http://pastebin.ca/681023
> 
> Thanks a lot for any info, and congratulations to all of you for your 
> terrific work with ALSA.
> 
> Pablo Hess
> _______________________________________________
> Alsa-devel mailing list
> Alsa-devel@alsa-project.org
> http://mailman.alsa-project.org/mailman/listinfo/alsa-devel

-- 
Tobin Davis  


What's page one, a preemptive strike?
		-- Professor Freund, Communication, Ramapo State College

Re: HDA Conexant: is mic boost possible?

[Pablo N. Hess]

 > I believe mic boost is on by default.  What model are you running this
 > as?  Laptop or Fujitsu?
 >
 > Tobin


I'm running it as model 'laptop'.

Any other hint at what might be causing this different behavior 
depending on the mic being stereo or mono, then?

In case someone needs it, I'll write again the quick description of the 
problem:

 > alsa-driver-1.0.14:
 >    playback: ok
 >    recording:
 >      stereo mic: ok
 >      mono mic: no input at all (very high volume already tried)
 >
 > alsa-driver-1.0.15rc1:
 >    playback: ok (even better than with alsa-driver-1.0.14)
 >    recording:
 >      stereo mic: ok (seems better than with alsa-driver-1.0.14)
 >      mono mic: *very* very low volume, bad quality, lots of low-volume
 > noise, too.

Thanks a lot,
Pablo