OP-X Pro II compatibility

What’s the status of Cantabile with regard to supporting the latest OP-X Pro II (1.2) ? It seems you can change patches within the OP-X Pro II GUI, but selecting patches via the Cantabile patch dropdown seems to result in a low frequency click/buzz. I notice there’s a Trello page alluding to some problems here. It would be interesting to know what the limitations are, and what the prospects are for full support at some time.


Hi Neil,

I’ve just had a look at this and there seems to be a couple of issues:

  1. The plugin doesn’t seem to always save it’s state correctly (in particular if no notes have been played the state seems to be saved in a corrupted state). This is the main problem that needs to be resolved but is outside my control.
  2. Because Cantabile saves a default “empty” state immediately after loading the plugin (and before any notes have been played) switching to any other pseudo-preset causes this corrupted empty preset to be loaded and the noises you describe. I think this is a direct side-effect of 1.
  3. There’s some unintuitive behaviour between Cantabile’s Pseudo Presets and OPX’s own bank/preset management where reloading a preset from the host overwrites the currently selected preset in OPX’s bank.

I’ve emailed Sonic Projects about all this to see if we can come up with at least a fix for 1 and 2 and maybe some better behaviour for 3.


Wow, that sounds pretty bad - presumably these or similar problems are happening with that plugin on other hosts too.

Thanks for your investigation work on this. Definitely going to stick with the previous plugin version on my live Cantabile machines!


Yeah, I’m in discussion with Sonic Projects about it. Hopefully we can at least get the first problem fixed (points 1 and 2) - that would make the plugin usable. The second problem (point 3) is just confusing but shouldn’t prevent use of the plugin.

Thanks for looking into this. Please reply to this thread (or some public place) with any updates. I am also very interested in this because I like that plugin’s sound but am very frustrated with its patch management and compatibility issues.

I’m experiencing the same behavior with the OP-X Pro II plugin, with both current and previous releases of the plugin. It’s one of my favourites, as well, so I hope these issues can be resolved.

Quick update - I’ve heard back from Sonic Projects they’ve reproduced the problem and are looking into it…


Here’s the latest from Sonic Projects:

I added a new special versions section in the login area when you scroll down where I added the Cantabile Edition and made a note about it in the introductory hints section. So OP-X PRO-II licensees can get the Cantabile Edition by logging in.

As said I haven’t have any time for intense long time tests yet, so for now it’s “as is”.
I hope this helps for now :slight_smile:

I’ve tested it quickly myself and it seems to basically work.


Fantastic, thanks Brad - I shall do some testing.


Thanks Brad and Sonic Projects! Looking forward to testing it out

I’ve just spent an hour or so playing with OP-X Pro II (x64 Cantabile Edition) in Cantabile 3171, and it works great - the problems from before all seem to have gone. Sounds magnificent, hasn’t crashed or had any other instability, and selecting patches via Cantabile pseudo-presets works great too.

Thanks for getting this sorted for us Brad!! :relaxed:


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Glad this is getting sorted out. Just recently got hooked on this vsti. A great sounding synth plug!!

I’m wondering if I’m doing something wrong. I’m still having issues around saving and loading patches. I downloaded the special Cantabile version of OP-X Pro II. Here’s my steps; maybe someone can tell me where my user error is occurring!

I added the plugin to a Cantabile rack, opened the plugin’s GUI, loaded a patch made it sure it sounded right, and saved the Rack. (I also have tried re-saving the patch from the plugin’s GUI at this point, but didn’t help either.) As long as I stay on the current song, everything is fine. (I think it’s also fine during the life of the current Cantabile session.)

But once I close Cantabile and load the song and rack containing that plugin, I would expect it to load the saved patch, or at least all of the parameter settings that make up the patch. But it always loads with the first patch in the default presets bank (“Matrix Softstrings II”) Ironically, the name of the patch that I saved DOES display in the patch name window, but the sound produced by the plugin is definitely the factory default, not my saved patch.

Has anyone else seen this behavior, or am I doing something wrong?


I am having the same behavior here on version 3172 using the cantabile version of op-x pro 2. The patch name is still in the window of the plugin gui but the patch number defaults to the first entry when reloaded. It is the same for loading op-x directly into a song as when it is put in a rack, it doesn’t store it and restore it. No unpleasant buzzing when switching though, that is gone.

Hi @Roland_Robertson and @dave_dore

I’ve just tried this here and can’t reproduce the problem. There is some weirdness around the way OPX handles the plugin’s saved state in that it always reloads the song on the the first patch int he standard library. I’ve raised this with SonicProjects and they’re aware of it, but it should affect reloading songs.

Can you guys try this with the simplest possible setup and see if we can isolate this down to something else perhaps? Try this:

  1. New Set Let (Set List Preloading off)
  2. New Song
  3. Insert the plugin
  4. Choose a different OPX preset
  5. Save the song
  6. Close Cantabile and reload

If that works, try the same steps again but this time putting the plugin in a new rack. Let me know.

OK I tried the procedure,

new set list, new song, loaded op-x

change preset op-x, save and close

reopened and here is how it looks

now it sounds the first patch (Matrix Softstrings II) but shows the name of the patch (X-Panded Mod Pad) i saved in the first slot of the plugin gui …

Thanks Dave. That is the same thing I see, but you’re illustrated step-by-step description is much better than my wordy paragraphs!

Hi Guys,

That looks exactly like what I see (and is what I tried to explain above about the weird preset management), but I definitely get the right sound. Are you sure you’re running the x64 Cantabile build that Sonic Project made?


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Hi Brad,

Yes I’m pretty sure

I redid all steps numerous times. The 1st preset sound comes up every time no matter what other preset i store the song with. Running win7 x64. Any thing else I can do to help troubleshoot?

Edit: I was testing this out on my online machine. When I set it up on my music machine it does work! I will test on my laptop as well. Not sure why it has problems on the online machine, will investigate further.

Any chance you’ve got both versions on the plugin on your plugin path?