[LAU] Default Jack metering (XFCE QJackCTL)

Len Ovens len at ovenwerks.net
Wed Oct 3 19:26:53 CEST 2018

On Wed, 3 Oct 2018, Dale Powell wrote:

> But my session configurations change all the time. I use QJackCTL to start Jack
> and pretty much everything autoconnects to the main two Jack outputs as expected.

And therein lies your problem. "Everything auto connects" to system_1/2. 
While this is a reasonable guess, it is just a guess and often wrong as 
many audio IF have different ports for headphones, monitoring and main out 
as well as digital (s/pdif). So auto connect works for a bunch of people 
but is wrong for everyone else.

> How would I change it so that instead of connecting to the System outputs to the
> audio interface they connect to the input of the MU1? Or is there another way to
> get it in the permanent signal path between Jack's System outputs and the
> physical audio interface?

Auto connect is not a part of jackd or it's specification. It is done by 
each application that chooses to do so. Some of them may choose to allow 
you to auto connect to another set of ports besides system_1/2 (I don't 
know of any off hand). However, the main problem with trying to have 
applications auto connect to anything other than system_1/2 is that 
anything else may not exist when jackd is started. So while things like 
Ardour will reconnect to whatever it was connected to the last time it was 
run, if what it was connected to last time is not yet started, that 
connection will not happen. A workaround that is still maybe not finished 
yet, is to run your jack application inside of Carla as a plugin. But 
jackd itself does not come with such infrastructure.

> with only a application window. Is the any Jack capable metering with a Widget
> for XFCE (either its own widget or works with Notification Area, not with the
> Indicator Plugin.) Something that will give little VU/PPM bars for left and right
> channels up on my toolbar and allow the main window to be closed.

Not that I have seen. The systray, indicator, notification area stuff 
seems to have been a moving target and getting stuff to work right with it 
has not been easy. Notification in xfce openes it's own floating window 
which may not be where you want it anyway. I would think a real window 
that you can put where you have space would be a better deal.

meterbridge -t dpm system:playback_1 system:playback_2

takes everything connected to playback_1/2 and reroutes them through the 
meter. However, anything started after meterbridge still connects to 

Len Ovens

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