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> JACK2 1.9.12 release and future plans
On 2017-12-21 by falkTX

A few days ago a new version of JACK2 was released.
You can grab the latest release source code at
The official changelog is:

  • Fix Windows build issues
  • Fix build with gcc 7
  • Show hint when DBus device reservation fails
  • Add support for internal session files

If you did not know already, I am now maintaining JACK2 (and also JACK1).
So this latest release was brought to you by yours truly. ;)

The release was actually already tagged on the git repo quite some time ago, but I was waiting to see if Windows builds were possible.
I got side-tracked with other things and 1.9.12 ended up not being released for some time, until someone reminded me of it again... :)
There are still no updated macOS or Windows builds, but I did not want to delay the release further because of it.
The 1.9.11 release (without RC label) was skipped to avoid confusion with the versions.
So 1.9.12 is the latest release as of today. macOS and Windows binaries still use an older 1.9.11 version.

Being the maintainer of both JACK1 and JACK2 means I can (more or less) decide the future of JACK.
I believe a lot of people are interested to know the current plan.

First, JACK1 is in bug-fix mode only.
I want to keep it as the go-to reference implementation of JACK, but not add any new features to it.
The reason for this is to try to get JACK1 and JACK2 to share as much code as possible.
Currently JACK2 includes its own copy of JACK headers, examples and utilities, while JACK1 uses sub-repositories.
During the course of next year (that is, 2018) I want to get JACK2 to slowly use the same stuff JACK1 does, then switch to use the same repositories as submodules like JACK1 does.
This will reduce the differences between the 2 implementations, and make it a lot easier to contribute to the examples and utilities provided by JACK.
(Not to mention the confusion caused by having utilities that work in simlar yet different ways)
We will keep JACK1 "frozen" until this is all done.

Second, but not least important, is to get the JACK1 specific features into JACK2.
A few things were added into JACK1 after JACk2 was created, that never made it into JACK2.
This includes meta-data (JACK2 does have the API, but a non-functional one) and the new internal clients.
The purpose is to reduce reasons users might have to switch/decide between JACK1 and JACK2.
JACK2 should have all features that JACK1 has, so that most users choose JACK2.

Now, you are probably getting the impression that the focus will be on JACK2, which is correct.
Though I realize some developers might prefer JACK1's design, the long "battle" of JACK1 and JACK2 needs to stop.
Development of new features will happen in the JACK2 codebase, and JACK1 will slowly become legacy.
Well, this is my personal plan at least.

Not sure if this all can be done in 2018, but better to take things slowly and get things done than do nothing at all.
I will keep you updated on the progress through-out the year.
Happy holidays everyone!

> Breaking changes in Carla Plugin Host
On 2017-11-21 by falkTX

Hello everyone, I have some bad and good news about Carla.
If you've been following the development on the git repository you likely know what this is about.
There were some major changes done to Carla's code base in the past few days.

The biggest change is the removal of the Juce library.
The reasons for this are well known by some developers, but I'll not write about them here.
After looking around for alternatives, I decided to fork an older GPLv2 compatible version of Juce and strip it down to the really essential parts needed to get Carla to build and run - even if it meant losing some of the features.
The possibility to change to an entirely different C++ framework crossed my mind, but the amount of effort and breaking changes would be too big.
I called the end result 'water'. You can say Carla doesn't need Juce, water is fine ;)
There's only a few classes and files needed for I/O, XML and AudioGraph handling, everything else is gone. \o/

The implications for this change are not big for Linux users, and is even a source of good news for other OpenSource Operating System users like FreeBSD and HaikuOS.
In short, because Juce is no longer there, we have lost support for VST3 and AudioUnit plugins.
Plus VST2 plugins on Windows and MacOS are now handled by Carla's code instead of relying on Juce.
This heavily reduces the amount of compatible plugins handled by Carla, because Juce had a lot of hacks in order to make a lot of commercial plugins run properly.
Also Carla on Windows and MacOS used Juce to handle Audio and MIDI devices, which now has been changed to RtAudio and RtMidi.
RtAudio & RtMidi are not as fully-featured as Juce was (we lose dynamic MIDI ports, for example), but I am glad to have Juce gone from the code-base.
(You can say that parts of it are still there, but my conscience is clear, and Carla remains self-contained which was my main point since v2.0 development started)

The next breaking change relates to the internal plugins used in Carla.
The plugins that already exist as LV2 will stop being exported with the carla.lv2 bundle.
Plus these plugins will soon be removed from the default build.
They quickly bloat the Carla binaries, as they include their artwork. Not to mention increasing the clone and building times.
The plan is to have them disabled by default and moved into a new repository as submodule.
Oh and the "experimental" plugins are going away soon. It was a mistake to make them Carla-specific in the first place, they should be regular audio plugins instead.

Another breaking change is the removal of modgui support.
The code only worked for PyQt4, which is no longer the default for Carla source-based builds.
Plus it required webkit, which brings a big list of dependencies. I would have to port the code to webengine/chromium to make it work with PyQt5... no thanks.

The final breaking change is the introduction of the Experimental option in Carla's settings.
Everything that is not stable at the moment went there as an option, and got disabled by default. This includes:

  • Plugin bridges
  • Wine options
  • Force-stereo mode
  • Canvas eye-candy
  • Canvas with OpenGL

All new in-development / testing features will get introduced as experimental first.
This will speed up the release of 2.0, since not everything needs to be finished for it.
For example, plugin bridges can still be there and not fully implemented, and we still have 2.0-stable out!

That's it! Thanks for reading so far.
In other news, I gave a small presentation about Carla in this year's Sonoj Conference.
You can check it out here:

Carla 2.0-beta6 will be out soon :)

> DPF-Plugins v1.1 released
On 2017-06-17 by falkTX

With some minor things finally done and all reported bugs squashed, it's time to tag a new release of DPF-Plugins.

The initial 1.0 version was not really advertised/publicized before, as there were still a few things I wanted done first - but they were already usable as-is.
The base framework used by these plugins (DPF) will get some deep changes soon, so better to have this release out now.

I will not write a changelog here, it was just many small changes here and there for all the plugins since v1.0.
Just think of this release as the initial one. :P

The source code plus Linux, macOS and Windows binaries can be downloaded at
The plugins are released as LADSPA, DSSI, LV2, VST2 and JACK standalone.

As this is the first time I show off the plugins like this, let's go through them a little bit...
The order shown is more or less the order in which they were made.
Note that most plugins here were made/ported as a learning exercise, so not everything is new.
Many thanks to António Saraiva for the design of some of these interfaces!


This is a collection of small but useful plugins, based on the good old LOSER-Dev Plugins.
This collection currently includes 3 Band EQ, 3 Band Splitter and Ping Pong Pan.

3bandeq 3bandsplitter pingpongpan


Studio quality, open-source reverb.
Its release was intended to provide a practical demonstration of Dattorro’s figure-of-eight reverb structure and provide the open source community with a high quality reverb.
This is a DPF'ied build of the original MVerb plugin, allowing a proper Linux version with UI.



Simple single-oscillator synth based on the Roland TB-303.
This is a DPF'ied build of the nekobee project, allowing LV2 and VST builds of the plugin, plus a nicer UI with a simple cat animation. ;)



Simple karplus-strong plucked string synth.
This is a DPF'ied build of the karplong DSSI example synth, written by Chris Cannam.
It implements the basic Karplus-Strong plucked-string synthesis algorithm (Kevin Karplus & Alex Strong, "Digital Synthesis of Plucked-String and Drum Timbres", Computer Music Journal 1983).



DPF'ied ports of some plugins from Niall Moody.
See for the original author's page.
This collection currently includes Amplitude Imposer, Cycle Shifter and Soul Force plugins.

amplitudeimposer cycleshifter soulforce


projectM is an awesome music visualizer.
This plugin makes it work as an audio plugin (LV2 and VST).


This is an OpenGL bars visualization plugin (as seen in XMMS and XBMC/Kodi).
Adapted from the jack_glbars project by Nedko Arnaudov.

> KXStudio 14.04.5 release and future plans
On 2017-06-11 by falkTX

Hello there, it's time for another KXStudio ISO release! KXStudio 14.04.5 is here!

Lots have changed in the applications and plugins for Linux Audio (even in KXStudio itself), so it was about time to see those ISO images updated.
Behind the scenes, from what the user can see, it might appear as nothing has truly changed. After all, this is an updated image still based on Ubuntu 14.04, like those from 2 years ago.
But we had a really big amount of releases for our beloved software, enough to deserve this small ISO update.
There is no list of changes this time, sorry. The main thing worth mentioning is that base system is exactly the same, with only applications and plugins updated.
You know the saying - if ain't broken, don't fix it!

Before you ask.. no, there won't be a 16.04 based ISO release.
When 2016 started KDE5 was not in a good enough shape, and it would need a lot of work (and time) to port all the changes made for KDE4 into KDE5.
KDE5 is a lot better now than it used to be, but we missed the opportunity there.

The current plan is to slowly migrate everything we have into KDE5 (meta-packages, scripts, tweaks, artwork, etc) and do a new ISO release in May 2018.
(Yes, this means using Ubuntu 18.04 as base)
The choice of KDE Plasma as desktop environment is not set in stone, other (lighter) desktops have appeared recently that will be considered.
In the end it depends if it will be stable and good enough for audio production.

You can download the new ISOs on the KXStudio website, at

And that's it for now.
We hope you enjoy KXStudio, being it the ISO "distribution" release or the repositories.

> Carla 2.0 beta5 is here!
On 2017-01-05 by falkTX

Hello again everyone, we're glad to bring you the 5th beta of the upcoming Carla 2.0 release.
It has been more than 1 year since the last Carla release, this release fixes things that got broken in the mean time and continues the work towards Carla's 2.0 base features.
There's quite a lot of changes under the hood, mostly bugfixes and minor but useful additions.
With that being said, here are some of the highlights:


Carla-Control is back!

Carla-Control is an application to remotely control a Carla instance via network, using OSC messages.
It stopped working shortly after Carla's move to 2.x development, but now it's back, and working a lot better.
Currently works on Linux and Mac OS.


Logs tab

This was also something that was brought back in this release.
It was initially removed from the 2.x series because it did not work so well.
Now the code has been fixed up and brought to life.

You can disable it in the settings if you prefer your messages to go to the console as usual.
Sadly this does not work on Windows just yet, only for Linux and Mac OS.
But for Windows a Debug/Carla.exe file is included in this build (after you extract the exe as zip file), which can be used to see the console window.


MIDI Sequencer is dead, long live MIDI Pattern!

The internal MIDI Sequencer plugin was renamed to MIDI Pattern, and received some needed attention.
Some menu actions and parameters were added, to make it more intuitive to use.
It's now exported as part of the Carla-LV2 plugins package, and available for Linux and Mac OS.

More stuff

  • Add carla-jack-single/multi startup tools
  • Add 16 channel and 2+1 (sidechain) variant to Carla-Patchbay plugins
  • Add new custom menu when right-clicking empty rack & patchbay areas
  • Add command-line option for help and version arguments
  • Add command-line option to run Carla without UI (requires project file)
  • Add X11 UI to Carla-LV2
  • Remove MVerb internal plugin (conflicting license)
  • Remove Nekofilter internal plugin (use fil4.lv2 instead)
  • Implement plugin bridges for Mac OS and Windows
  • Implement Carla-LV2 MIDI out
  • Implement initial latency code, used for aligned dry/wet sound for now
  • Implement support for VST shell plugins under Linux
  • Implement sorting of LV2 scale points
  • Allow to scan and load 32bit AUs under Mac OS
  • Allow using the same midi-cc in multiple parameters for the same plugin
  • Allow Carla-VST to be built with Qt5 (Linux only)
  • Bypass MIDI events on carla-rack plugin when rack is empty
  • Find plugin binary when saved filename doesn't exist
  • Force usage of custom theme under Mac OS
  • New option to wherever put UIs on top of carla (Linux only)
  • Make canvas draggable with mouse middle-click
  • Make it possible to force-refresh scan of LV2 and AU plugins
  • Plugin settings (force stereo, send CC, etc) are now saved in the project file
  • Renaming plugins under JACK driver mode now keeps the patchbays connections
  • Update modgui code for latest mod-ui, supports control outputs now
  • Lots and lots of bug fixes.

There will still be 1 more beta release before going for a release candidate, so expect more cool stuff soon!

Special Notes

  • Carla as plugin is still not available under Windows, to be done for the next beta.


To download Carla binaries or source code, jump into 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 into the Carla's Github project page for those.

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