[ubuntu-studio-devel] ubuntustudio controls

Len Ovens len at ovenwerks.net
Sat Jun 14 15:33:13 UTC 2014

On Sat, 14 Jun 2014, Kaj Ailomaa wrote:

> Make sure to look through what has already been planned, primareily at
> https://wiki.ubuntu.com/UbuntuStudio/UbuntuStudioControls. Either Len or
> me can update that page with new content.

Looking through the wiki we have system check and jack control. It seems 
some things are duplicated. I am thinking the system check might run at 
boot time and leave a file laying around with it's analysis. Then there 
would be a settings application (in the settings menu... although it may 
make sense to use it to replace pavucontol in the sound indicator).
This settings application could be the same as the jack control 
application, but opened with --settings or it could be a separate 
application. In either case, it would seem that there needs to be 
interapplication communication. A settings app would need to tell 
jackcontrol that settings have changed: please use them. SIGHUP would be 
enough for this. Or something that sees another instance of jack control 
is already running and pass that instance a message that says open the 
settings window and raise it. Perhaps another common SIG*. Dbus 
communication is another possibility.

What I am saying is that the jack control user interface needs to be 
really lean. Click the icon and only one more click to do what needs doing 
from a short list... The systray icon for qjackctl for example is too long 
in my opinion. It would be nice if the latency slider could be set up like 
the volume slider in the audio indicator is now.

Jack start/stop: If settings has jack running at session start up... this 
should probably be greyed out or at least greyed out except in advanced. 
There could be an Unstick Jack button that kills jack and restarts. One of 
the problems we deal with many times on our support chanel is some 
application starts jackd before jackdbus is running. Having jack run all 
the time would fix this. If jack defaults to high latency startup, there 
is no resource problem with using jack as the default pulse device. I 
understand this goes beyond just the contols application and gets into 
system setup. Another possibility would be to add a killall -9 jackd to 
the start button. BTW running "jack_control start" can be done at any time 
even if jackdbus is already running with no problems/hickups.

I have been running jackdbus as my sound server for over a month now with 
complete reliability.  Pulse feeds jack (when I want it to) and latency is 
adjusted on the fly. Pulse has all alsa cards turned off. I really think 
this is the way to go. It would be nice if we could have a front end for 
jack that looked to applications like pulse but was smaller... but when I 
look at what people expect pulse to do (surround sound for example) I 
don't know how much smaller it could be made. Perhaps have a user config 
for pulse that loads fewer modules.

Just as an aside, we should come up with a name for this jack control so 
we don't get it mixed up with jack_control. If we feel it has wider 
application than just UbuntuStudio the name should indicate that.

I have some family stuff I want to do but will continue some of my 
thoughts later.

Len Ovens

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