KXStudio - Carla

[DoosC]

Hi everyone,

I want to introduce an emerging killer app from KXStudio (and I bet this won't be the only one!).
Yesterday I just tried "Carla" which is a multi-plugin host for jack.
I you love Jack Rack and LV2 rack, take both add a ton of awesomeness and you get Carla.
It is just amazing, you can load either DSSI, LV2, VST or LADSPA plugin and you get all the available input/output in jack.
This is a nice piece of software already and said to be still under developpement, I can't wait to see what the 1.0 version will be able to do !
You can even assign just every plugin parameter to a midi controller. I think this is one of the killer features for live or automation.
I didn't get that lucky with that feature because whenever I trigger a parameter from my Modulation wheel for example, I just get a ton of Xruns and that sounds awfull. Anyone tried it with more success ? Maybe it is just because it is still under developpement.

Anyway keep up the good work KXStudio team, this is crazy !

[i2productions]

I wish this had been out when I did my review a few days ago, I did the update yesterday, and it's awesome, I might do a quick video review of just this app. I'm gona try out the MIDI control tonight and see what happens. Definitely a very cool rack, falkTX just keeps making life better and better!

[i2productions]

As of course, I will respect your wishes, but why would you not want the world to
know about, and test out an awesome rack? People undertand its pre-alpha, there's just many people that want to see and test. But until I hear otherwise I will respect your wishes and not review it.

[DoosC]

Because there's no save/load support, I'll probably need to change the internals to handle the required stuff for a proper save (XML?)

Take a look at rakarrack preset file (File -> Save preset), open it as text, it looks pretty simple and effective. Or the kde desktop files are also simple and effective (same as rc files for plasma or other kde rc files). Maybe xml is a little bit too much for preset files. Just a thought.

BTW, anyone willing to do some nice icons?

Nice icons is definitely a must.
Maybe we should ask to some icon designers like Thorwil or Nuno Pinheiro, I can do that if you agree ?

[DoosC]

I don't know who Thorwil is

He's a talented designer, and as advertised on his blog he also cares about free software : "Thorwil's - Design for Free Software"

Check his blog and his work, I think you will like his approach :
http://thorwil.wordpress.com/

PS: did you know that in Luxembourg, where I live, there is 15% of the population that is from Portugal ? Amazing !

[DoosC]

Ok, things are going for a new GUI

great news !

The big red led button looks fine to me, so I think I'll keep it.

agreed

The next 2 areas (plugin name + buttons and main controls) still need a texture rework)

maybe just some alpha blending ?

I'm unsure about the big black area...
Should it have a VU? maybe horizontal meters? or maybe even a FFT-like spectrum visualizer?

I would go for two stereo horizontal VU, one for the input signal, one for the output signal. Usefull to calibrate the rack with the volume button you added in case of clipping at some stage of the rack.

[scalawag]

Ok, things are going for a new GUI, but I need some help now...

This is the current look:
http://kxstudio.sourceforge.net/tmp/scr008.png

The big red led button looks fine to me, so I think I'll keep it.
The next 2 areas (plugin name + buttons and main controls) still need a texture rework)

I'm unsure about the big black area...
Should it have a VU? maybe horizontal meters? or maybe even a FFT-like spectrum visualizer?

What do you think?

I think you sould make the button red when OFF and green when ON.
I'll make the 2 areas a little bit transparent so we can see the background texture.
I think the colors to separate the plugins are a great idea, and so one background should be enough. I like the one in the middle. it looks more professional.
A VU will be great.

[DoosC]

More work: http://kxstudio.sourceforge.net/tmp/scr009.png

Yeah VU ! As for the colours, I would have gone for the usual green to red (with yellow in the middle). And with vertical dashed line rather than plain bar. But still great nonetheless !

But I think I'll keep the GUI as it is for now (I need to focus on the audio/DSP code now)

Wise. The inner processing should be the primary focus. But often apps with a bad look and feel use to keep it for a long time, so carrying a little bit about it at first shouldn't hurt

I'm open to new ideas though

I don't doubt it. You seem to care a lot about users feedback

[DoosC]

Nice ! It's shaping fast.
I can't wait to see it updated in the KXStudio repos.

[DoosC]

The "bad" thing is that the content is no longer aligned with each other.
Still, what do you think?

To my opinion that looks really confusing.
Is it possible to just grey out the useless knob or to put an empty place the same size of the useless knob so in both case that stays aligned ?

If you have any feature requests for Carla, now it's time to speak, as I'll soon begin to work on other projects.

So that means that you're going to upload the lastest version to the KXStudio repos soon ?
I can't wait to try it, as since the lastest update it became unusable :

Code: Select all

Traceback (most recent call last):
  File "/usr/share/cadence/src/carla.py", line 1681, in showPluginDatabase
    dialog = PluginDatabaseW(self)
  File "/usr/share/cadence/src/carla.py", line 186, in __init__
    self.loadSettings()
  File "/usr/share/cadence/src/carla.py", line 454, in loadSettings
    self.reAddPlugins()
  File "/usr/share/cadence/src/carla.py", line 318, in reAddPlugins
    plugin = self.strPyPluginInfo(plugin)
  File "/usr/share/cadence/src/carla.py", line 278, in strPyPluginInfo
    pinfo['category'] = qt_pinfo[QString('category')]
KeyError: PyQt4.QtCore.QString(u'category')

So what are these new projects ? Spread some spoiler !

[hellalive]

Can't wait to try this! Having the VST's as LV2 would be awsome - i really like LV2 plugins.

Anyway, i think you should get a default lenght for the meter - most important - and get in as much knobs as the plugin needs, then leave empty space if needed. Or mark the unused knobs as "not avaiable", and just leave those at 0. I don't think having a similar plugin on the side would be good..just get here an image (like a metal plate, some logo...).

The feature where you could save the whole project with all plugins setting would be very cool. Falk, your work is GREAT!

[DoosC]

For plugins that have no audio input or output, remove the VU, and make space for a new similar plugin (no audio ports), which stays on the right.

Same remark as hellalive, I would leave a plugin per line and not reuse the VU space.

Just delete ~/.config/Cadence/Carla-Database.conf and restart Carla.

Yeah ! Working again !
I tried it again, and even if it is not the latest version, I'm pretty impressed !
The midi control of the parameters now work as expected with not a single xrun, awesome !

and get in as much knobs as the plugin needs, then leave empty space if needed.

I don't quite agree with that, the UI would be so clogged that would make it unusable. The midi control feature is here for that: if you want to control a lot of parameter at once then you can do it with a midi controller.

The feature where you could save the whole project with all plugins setting would be very cool.

I this the whole thing wouldn't make sense as a rack if this feature is missing, think lv2-rack and jack-rack, they both have it. Carla is much superior to those two great apps, the project saving feature really is desirable.

If you have any feature requests for Carla, now it's time to speak, as I'll soon begin to work on other projects.

Ok now that Carla is working again on my computer, I tried it again on a real life use case, and I'm missing to options :

1) The auto connect feature of each rack stage "à la" jack-rack. But that should only be on option, so you could be able to switch between jack-rack behaviour (auto connect) and lv2-rack behaviour (manual connect). So very different use case could be possible with no hasle (for the user at least).

2) I would like to see a similar but not identical feature for the midi part. It would be great to have an option to choose to expose a single midi-in for Carla, or to expose each midi port of each plugin. The use cases would be i) I connect a single midi-out of a controller to carla and want to control everything from it (be it hardware or software like your XY midi controller) or ii) connect each plugin individually to midi automation tracks from a sequencer.

To summarize, with these two options and the save/restore project feature, Carla would be close to perfection

One last thing on my wishlist for the perfect rack : being compliant with the highest ladish possible level
That would not be perfection... but weapon of mass destruction

[thorgal]

hello falkTX, nice stuff you're doing here

I tried Carla from git. Compiled and started fine but it only detected my LADSPA plugins (no VSTs, no LV2s, no DSSIs). Isn't it strange ?

[hellalive]

So Falk, if Carla should be itself a plugin i could be able to load it in my DAW and using it as many racks - let's say at least one per track? It would be REALLY interesting..this made me think about adding the possiblity to load different racks in a single instance - let's say i have 2 inputs on my soundcard and i'm recording bass guitar and vocals; it would be cool to have rack1 for bass - with comp, eq, etc; and rack 2 for voice - with eq, delay, reverb...the important thing would be not having too much resources usage, expecially when loading several racks in a single DAW project - with single effects loaded on much tracks, busses, etc my most complicated ardour projects sometimes have troubles loading.

For the too-many knobs issues, i would suggest the possibility to display "optional knobs" in a rack space below the loaded plugin - so it would eventually occupy 2 rack units (vertically). Not essential, though.

[spm_gl]

A couple of random remarks:

1. I hate wet-dry controls. Either a plugin is meant as an insert, i.e. it replaces the original audio with a processed version, or as a send effect, who's output should go into it's own mixer channel. But that's sadly the old-fashioned correct way of doing things.

2. It's balance, not pan. Only mono signals have panorama, stereo signals have balance.

3. You could re-use the dual VU for synth plugins, by displaying the midi velocity in the input

4. You could have a dual-flip-view kinda thingy. Have the balance, mix, and routing (chain effects internally) hidden behind the "front plate", and a view option to switch between this and the default.

Sorry if I sound a little pedantic at times, been teaching too much I guess.