[LAU] Full-featured mixers

Len Ovens len at ovenwerks.net
Sun Mar 31 23:02:32 CEST 2019

On Sun, 31 Mar 2019, Tim wrote:

> I found a tip for KMix to show ALSA *not* Pulse controls:
>   "export KMIX_PULSEAUDIO_DISABLE=1 && kmix"
> But unfortunately it's either Pulse or ALSA, not both at the
>  same time in KMix. To me that's a bad thing.

Pulse and alsa are effectively two different audio "devices".

Pulse does weird things with the alsa controls for most alsa mixers, 
Thankfully, the ice1712 is one of the ones it does not touch :)
However, if you watch the alsa controls for input levels on an HDA card (I 
know, the input on these is not worth using for anything beyond phone 
work) The boost and level controls bounce all over the place such that a 
lower level may have more boost (and more noise) than a higher level. It 
also means that after setting the alsa level exactly how you want it, 
pulse comes along and messes it up.

> So I want to give a big shout out for QasMixer
>  https://sourceforge.net/projects/qastools/
>  and ask what general mixers you might use and what
>  you think of QasMixer and QasHctl. They're pretty cool.
> They show all my ice1712 controls.

I like qasmixer except it does not allow one to edit the layout. On my 
ice1712 it does show all the controls including duplicate ADC and DAC 
controls. I would like to be able to not show duplicates (or is this just 
a Delta 44/66 problem).

In the end, I tell pulse not to look at any alsa devices and to use jack 
as it's only device. In this case it only does sw levels (-inf to +11db).

> I think a desktop mixer icon should eventually bring you
>  to something like that instead of only Pulse.
> What do you think?

One word "convergence"... All computers must be the same to operate as a 
phone. After all nobody does real work on a computer, they just browse and 
use one or two other apps at most. Most phone users just want one level 
control... The reality is that PCs are not made for audio creation, they 
are entertainment boxes. "Low latency" is 30ms by design, if you got less 
it is because they made a mistake and "should" have used cheaper parts. If 
they make an audio computer with super low latency (10-15ms) it will be at 
musician prices (think brand new Gibson Les Paul).

Anyway, yes I agree. On the other hand, when I use a browser to watch YT 
stuff, the Pulse single level control is just perfect and because of the 
way I use my Delta66, my alsa level controls are pretty much set and forget 
anyway. They are line level and so I have a cr1604 in front of it for 
mic/line preamps and speaker level controls. I do not use the internal 
monitor mixer because I have the external one that has faders and eq and 
sends and all that so I don't need to. Mixers are cheap, even digital ones 
with 32 ADC/DAC built in that can also act as DAW controlers. (stay away 
from new A&H SQ series which 96K only and is not stable when used with 
Linux and maybe other OS as a digital interface)

Len Ovens

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