Ardour is not loading calf studio gear

Installation & Configuration Linux
#1

Hi,

I am kind of new to Ardour and DAWs in general so forgive me if I get something wrong.
I am using Ardour 8.12.0 on Linux Mint and I installed Calf plugins from the software manager and they do display in the plugin selector but when I try to load them they don’t load and it displays an error message like this:

The plugin “Calf Equalizer 12 Band” could not be loaded

See the Log window for more details (maybe)

I found another topic here with the same issue but I couldn’t really figure out how to solve it because I don’t use JACK

Error log: 2025-05-26T16:12:46 [ERROR]: LV2: Failed to instantiate plugin http://calf.sourceforge.net/plugins/Equalizer12Band
When I try to enter that website it also doesn’t work, so I am not sure if this is a problem with Ardour itself. I already tried restarting Ardour, rescanning the plugins and reinstalling them.

Any help is appreciated.

#2

CALF plugins use the GTK2 GUI toolkit. It is no longer possible to use them with Ardour. There are lots of other reasons to not use them.

Please search these forums for more responses and explanations.

#3

Ah I see, thank you for the quick reply!

#4

Meh,

It’s still possible, but not advisable…

Deb package here (should work with Mint):

https://launchpad.net/~kxstudio-debian/+archive/plugins/+files/lv2-gtk-ui-bridge_0.1-1kxstudio1_amd64.deb

#5

Weird, I just saw this topic by accident. I use (and like, and yeah I know about the controversies) the Calf Suite and it’s working just fine right now. Anyone know why it works well for me?
I’m on Ardour 8.12.0 with Calf 0.90 on a recently patched Arch.

Edit: Well, probably because I have the GTK2 packages installed

#6

If you are using an Arch packaged Ardour and an Arch packaged Calf using the same GTK2 version it will work, some other lucky combos may work but most don’t. The LV2 UI hack above makes it work on pretty much all systems.