Re: [Jack-Devel] How to control playback volume of loopback->JACK chain?

> Date: Thu, 22 Dec 2011 05:18:58 -0800 (PST)
> From: James Warden <[hidden]>
> To: "[hidden]" <[hidden]>
>
>
>
> Hello,
>
> Back in the days when I was hacking my way through to get the loopback method to work, I experimented with the "softvol" ALSA plugin.
> If you want to have the volume control on the loopback device, just modify your .asoundrc like this in the !default section (I commented out the former stuff and added a "softvol" section instead, assuming that you are using the same naming as found in my TWIKI page):
>
> # ------------------------------------------------------
> # default device
>
> pcm.!default {
> #  type plug
> #  slave.pcm "aduplex"
>
>   type softvol
>   slave {
>       pcm "aduplex"
>   }
>
>   control {
>       name "aduplex"
>   }
>
>   min_dB -51.0  # 
>   max_dB   0.0
> }
>
> # -------------------------------------------------------
>
>
> Try this and see if that fulfils your need.

I suppose that would work for a static volume level, to code
the gain in the max_dB and min_dB values.  However, alsamixer
would not come up when talking with "-D default" or without
the -D option.  I tried the above and a few variations on the
name in the control {} block based on the URL from an earlier
message.  Nothing appeared to allow real-time changes in
volume level.

Fwiw: I think I have a fall-back plan to exchange a public
key at login time on the X terminal (aka zero client) that
should allow ssh to run alsamixer on the terminal's physical
hardware sound card(s) displaying via an ssh tunnel to the
VNC X server running on the server (where all the apps run)
that will be viewed by the VNC viewer back on the X terminal.
That's insanely complex, but with the VNC viewer in full-screen
mode, that's about the only way I can see to do it if softvol
can't be connected to by alsamixer.

Thanks,

Robert

1324877144.7078_0.ltw:2,a <20111226052523.7306326484 at one dot localnet>