alsa mixers

[Kaj Ailomaa]

On Wed, May 8, 2013, at 07:09 AM, David Henningsson wrote:
> On 05/08/2013 12:15 AM, Len Ovens wrote:
> > I looked at a number of audio mixers: (I used three audio IFs, an old
> > ens1370, An intel HDA (most common internal audio) and an ICE1712
> > multitrack card)
> >
> >    pavucontrol and kmix: These both control pulseaudio and only affect ALSA
> > settings of any sort through the pulse audio interface. kmix is the the
> > kde version pavucontrol. There is no reason to attempt to make kmix or
> > pavucontrol work without PA running, rather they should stop running
> > gracefully if PA is not there.
> I think this is because /usr/share/alsa/pulse-alsa.conf has this entry 
> in it:
> 
> ctl.!default {
>      type pulse
> }
> 
> ...making the default ctl (i e mixer) interface the pulseaudio one.
> 
> Alsamixer (the ncurses version) has a specific patch to ignore the 
> pulseaudio interface, but you can still get to it if you do "alsamixer 
> -D pulse".
> 
> 
> > We need a new mixer!Lets think about what a dream recording alsa mixer
> > would be like. Then we can think about building it. What controls should
> > be available? what screens should be included? What gui tool kit should be
> > used? I would think basing the ideas on mudita might be a place to
> > start... but then I have not used any of the other HW specific mixers and
> > there may be better ideas. I would suggest starting with the Intel HDA and
> > AC97 HW.
> 
> Before rushing away to write yet another mixer, may I suggest that you 
> first look at the current choices a bit and see if it is possible to 
> improve them to do what you want? This does not only have the benefit of 
> saving you some work to get the basic stuff up and running, it also 
> makes the final product fit more use cases than just yours (and as a 
> result, you'll get help finding/fixing bugs and so on). And, many 
> upstreams are longing for more contributions and a wider user base.
> 
> 

I agree. All of the desktop environments seem to have their own mixers
at the moment. So, either one should add stuff to all of those, or pick
one that would suit all DEs and work on making it more versatile.

There should only be need for one mixer application for ALSA devices, no
matter if PA is running or not.
The design of the PA mixers is only including controls for PA profile
based controls. It's lacking the full set of HW controls for the device,
which is quite logical from the PA users point of view. But, as soon as
one is not using PA, the mixer becomes next to useless.

Here's a design idea for such a mixer. It has two

1. PA view - The main controls are categorized and sorted for the PA
profile (like they are now). To see full list of ALSA controls, one
needs to toggle the view to "ALSA view", and in that full view, one
clearly sees which controls are used by PA and which are not.
2. ALSA view - no PA controls if PA is not running, and the overview is
categorized and sorted from a ALSA perspective (like in alsamixer).

That would make the main mixer have all you need for controlling your
card. 

One could even go further with adding support for jack (jackdbus), and
therefore, also for ffado.