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> Changes in KXStudio repos, regarding Carla and JACK2
On 2019-03-22 by falkTX

This is a small notice to everyone using Carla and JACK2 with the KXStudio repos.

First, in preparation for Carla 2.0 release, the (really) old carla package is now the new v2.0 series, while carla-git now contains the development/latest version.
If you are not interested in testing Carla's new stuff and prefer something known to be more stable, install the carla package after the latest updates.

Second, a change in JACK2 code has made it so a restart of the server is required after the update.
(but for a good reason, as JACK2 is finally getting meta-data support; this update fixes client UUIDs)
If you use jackdbus (likely with KXStudio stuff), you will need to actually kill it.
If that does not work, good old restart is your friend. :)

One important thing to note is that the lmms package now conflicts with the carla-git one.
This is because some code has changed in latest Carla that makes v2.0 vs development/latest ABI-incompatible.
In simpler terms, LMMS can only either be compiled against the stable or development version of Carla.
The obvious choice is to use the stable version, so after the updates if you notice LMMS is missing, just install it again.
(If you have carla-git installed, carla will be installed/switched automatically)

I tried to make the transition of these updates as smooth as possible, but note that you likely need to install updates twice to complete the process.

In other news, we got a new domain!^-^)/
Also Carla v2.0 release date has been set - 15th of April.
Unless a major issue is found, expect a release announcement on that day.
See you soon then! ;)

> Carla 2.0 RC4 is here!
On 2019-03-02 by falkTX

Hello again everyone!
This is a quick fix for the Carla Plugin Host (soon-to-be) stable series.


  • carla-vst: Add Ardour workaround for its 'Analysis' window
  • carla-vst: Fix typo leading to buffer size of 1 during plugin activation
  • Fix for some stupid plugins messing up with global signals (restore original signals after creating plugin)
  • Fix dry/wet for VST plugins (by creating extra buffer for inline processing)
  • Fix crash in RtAudio when ALSA soundcard is listed but not available
  • Fix crash on JACK buffer size changes in patchbay mode
  • Fix crash when directly loading vst shell plugins (carla-single or drag&drop dll file)
  • Fix loading multiple exported LV2 plugins (always copy full carla-plugin binary when exporting)
  • Fix missing transport information when Carla is not jack transport master
  • Fix opening a few VST2 UIs (we give up trying to follow VST spec, always assume UI opens nicely)
  • Fix plugin bridges not working under Fedora (RT threads were able to be setup, but not started)
  • Automatically terminate wine bridges if main carla dies
  • Calculate VST2 ppqPos in a more reliable way
  • Do not set up RtAudio in "hog device" mode
  • Do not build external plugins in debug or strict build
  • Handle more sources of VST2 automation via audioMasterAutomate
  • Handle worst-case scenario of carla-plugin buffer size being too low

I am not confident enough to call it the stable version just yet, as some of these release changes actually introduced new code.
But the target date for the stable release is now set - middle of April.
There are no more release-blocker bugs for Carla v2,0 anymore, so it is just a matter of time now.


To download Carla binaries or source code, jump on over to the KXStudio downloads section.
If you're using the KXStudio repositories, you can simply install "carla-git" (plus "carla-lv2" and "carla-vst" if you're so inclined).
Bug reports and feature requests are welcome! Jump on over to the Carla's Github project page for those.

> DPF-Plugins v1.2 released
On 2019-03-02 by falkTX

Hello everyone, a new release of DPF-Plugins is here.
This is mostly a bugfix release, with a few little new things.
This is what changed compared to the last release:

  • Fix glBars and ProM plugins not being built and installed
  • Kars: Added release and volume parameters
  • Kars: Remove its useless UI
  • Nekobi: Add enum values for waveform parameter
  • Remove modguis, they are maintained in a separate repo

DPF changes

DPF (the small framework behind these plugins) saw some important changes.
They are not all relevant to DPF-Plugins directly, but worth mentioning:

  • Fix samplerate property in lv2 UIs
  • Fix (implement) parent window for about dialogs for MacOS and Windows
  • Add get/set scaling to Window
  • Add option to automatically scale plugin UIs
  • Allow plugin UIs to be user-resizable, test with info and meters example
  • Implement basic effGetParameterProperties in VST2 plugins (boolean, integer and log flags)
  • Implement midi out
  • Implement enumerator style of parameters
  • Implement LV2-trigger-type parameters
  • Implement Shift-click to reset sliders
  • Report supported LV2 options in generated ttl
  • Render VST2 parameter-text integer, boolean and enum parameters
  • Rework calculation of VST2 transport/time info
  • Set _NET_WM_WINDOW_TYPE for our X11 windows

Other things worth noting is that 2 new exciting things are currently under development: Cairo graphics support and AU plugin wrapper.
Eventually these will be part of core DPF, but for now they are being discussed and worked on with other developers.


The source code plus Linux, macOS and Windows binaries can be downloaded at https://github.com/DISTRHO/DPF-Plugins/releases/tag/v1.2.
The plugins are released as LADSPA, DSSI, LV2, VST2 and JACK standalone.

> Carla 2.0 RC3 is here!
On 2019-01-15 by falkTX

Hello everyone, happy new year!
This is a quick fix for the Carla Plugin Host (soon-to-be) stable series.
Only very small fixes here, and a change on how specific plugins load.
This release starts a "release early, release often" attitude, that hopefully I can maintain from now on.


  • Fix bridge-lv2-x11 crash when manually started from CLI
  • LV2: Don't prefer plugin bridges for certain hardcoded plugins (Calf, ir.lv2 and v1 series)
  • VST: Do not call plugin effEditIdle on update display opcode, fixing crashes for a few plugins

Previously a few plugins were hardcoded to run as plugin bridges, as they were deemed unsafe because of how they use their plugin UIs (instance-access).
Carla automatically started these plugins as bridges, as to not crash the main process when Gtk and Qt gets in the way.
Plugin state in bridges have a few issues (as plugin bridges are experimental right now), which I was hoping to fix before the final 2.0 is here.
But that will not happen it seems (not an easy fix), so now these plugins will run normally as all others do, in the same process.
This means the following possible breaking changes:

  • If v1 plugin series are compiled with a Qt version different than the one Carla is using, expect a crash on load or soon afterwards
  • Calf plugin UIs will be missing their graphs by default, unless you disable running plugin UIs in bridge mode in Carla settings

This is not an issue for other plugin UIs that use Qt or Gtk, as they do not use LV2 instance-access.
Carla runs Gtk and Qt LV2 UIs in a separate process, but because these UIs require direct access to the plugin instance, they cannot be bridged.


To download Carla binaries or source code, jump on over to the KXStudio downloads section.
If you're using the KXStudio repositories, you can simply install "carla-git" (plus "carla-lv2" and "carla-vst" if you're so inclined).
Bug reports and feature requests are welcome! Jump on over to the Carla's Github project page for those.


A "2.0-final" milestone is on GitHub, which lists the remaining issues to be fixed before 2.0 is considered "final".
New features already made its way to Carla, but sit on the develop branch.
When the "final" version is released, expect a 2.1-beta to come shortly afterwards.

> JackAss v1.1 release
On 2019-01-15 by falkTX

This is a tiny bugfix for JackAss, a VST plugin that provides JACK-MIDI support for VST hosts.

The only change is that Wine 64bit builds work now, so you can finally load it inside 64bit Windows applications running on GNU/Linux via Wine.
Tested to work with FL Studio 20.

You can find JackAss source code and bug tracker in Github, at https://github.com/falkTX/JackAss/.

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