JJazzLab 5.2.1 (April 13, 2026)

JJazzLab Dark JJazzLab Dark JJazzLab Spain Demo    

New features 5.2.1

  • “Freeze bug” fixed
    Not a new feature, but the fix was the opportunity to improve JJazzLab internal design for better stability.

  • Define a restart bar when playback is in loop mode
    Useful for simple practice songs for which you dont want to bother creating a song structure.

  • User interface improvements
    In lead sheet editor, song structure editor, mix console.

  • Adjust FluidSynth audio driver [linux]
    This should help solve linux-specific audio configuration issues.

  • New MIDI remote commands : play selection, toggle loop mode, change style variation
    For example this lets you command a style variation change while playing in arranger-mode.

  • Many bugs fixes as usual

🠊 check out the 5.2.1 RELEASE NOTES for the complete list of changes with screenshots.

Download

If you run into any installation issues, see the detailed installation instructions in the online documentation.

Windows

Download and run: JJazzLab-5.2.1-Win64-Setup.exe

If you get a Windows security popup when running the installer, this is normal: the installer was not “code-signed” with a developer certificate.

Why? This would cost me about $100/year. JJazzLab is 100% free with no ads, I just can’t.

JJazzLab is NOT malware! You can verify the download using the SHA256 checksum key available here.

So to run the installer, just choose Run anyway in the security popup.

Mac

You must first install FluidSynth yourself (version >= 2.2.0, I recommend via homebrew).

Then download and install:

Consult the installation instructions for MacOS for more details.

If MacOs prevents you from opening the .pkg file for security reason, this is normal: the .pkg file was not “notarized” via the Apple process.

Why? Notarization would require me to pay $100/year to Apple and to buy a MacBook. JJazzLab is 100% free with no ads, I just can’t.

JJazzLab is NOT malware! You can verify the download using the SHA-256 checksum available here.

To open the .pkg file anyway, go to Systems settings/Privacy & Security, scroll-down to the Open anyway button, as explained in this Apple online doc.

Linux Ubuntu/Debian family (x64)

Download the .deb file and install it as shown below.

jjazzlab_5.2.1-1_amd64.deb

sudo apt-get install ./jjazzlab_5.2.1-1_amd64.deb    # this will also download and install fluidsynth (>=2.2.0) if required

If FluidSynth makes some “crackling” noise, make sure your Linux is optimized for audio applications.

Linux OpenSUSE family (x64)

Download the .rpm file and install it as shown below.

jjazzlab-5.2.1-0.x86_64.rpm

sudo zypper install ./jjazzlab-5.2.1-0.x86_64.rpm      # this will also download and install fluidsynth (>=2.2.0) if required

If FluidSynth makes some “crackling” noise, make sure your Linux is optimized for audio applications.

Linux others (x64)

You must first install FluidSynth (>=2.2.0) yourself.

Then download and extract the tar.xz file as shown below.

JJazzLab-5.2.1-linux-x64.tar.xz

tar -xf JJazzLab-5.2.1-linux-x64.tar.xz

Run file bin/jjazzlab to start JJazzLab.

If FluidSynth makes some “crackling” noise, make sure your Linux is optimized for audio applications.

Consult the INSTALLATION INSTRUCTIONS ON LINUX if required -distribution on the many Linux distros is not always easy…

Older versions

Older versions from 4.0.2 can be found in the JJazzLab releases page on GitHub (see Assets).

Free and open-source software

Contribute to the code on GitHub.

If you’re not a developer, you still can help:

Acknowledgements

Let us be grateful to the people and projects that are or were a part of JJazzLab, or those who had contributed to it in some way.