What are "Harrison XT plugins and ACE plugin GUIs" and do i want to install them?

The installation routine offers me to decide "Install Harrison XT plugins and ACE plugin GUIs? [Y/n]: "

But I miss information that I can base my decision on.

They might be interesting plugins, but it’s not clear to me if they come for free, or if i can just install them, but then still have to buy a license at Harrison for them.

I checked a few threads here but don’t find clear information - the manual says nothing at all about this - just “follow the prompts”.

Appreciate a hint - and I think it would be helpful if the installation script would be more clear about that.

The XT Plugins are unlicensed demo plugins from Harrison. They are excellent stable plug-ins and worth a try. The demo version fully works, but has a nag in the GUI to register. They do not disable or blast noise into the signal.

The ACE plugin GUI’s are GUI’s for the included fully functioning, non-demo ACE plug-ins. No reason to not install them.

You Get something like :

instead of a basic LV2 GUI:


I forget, is it possible to install the ACE UI without the Harrison demos?

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No, not currently.
Then again apart from requiring ~40 MB additional disk space there is no downside, and you can open and play sessions that use those those plugins.

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Am I correct in assuming the Harrison plugins are proprietary while the ACE GUIs are free software? I’ve never installed the GUIs for this assumption anyway.

The Harrison GUIs for the ACE plugins are closed source.


Aha that explains it. I will continue to live without them then.

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While I’m generally fine to pay for good, also closed source software, we have no shortage on open source plugins and having a choice and have enough information to decide is great :wink:

The ACE-plugin GUIs use the same proprietary toolkit as the XT plugins.

LV2 plugins have a strict separation between DSP and GUI. It is possible to add a GUI without even modifying the original DSP (pretty awesome). So a 3rd party can provide a custom GUI to any LV2 plugin.

For various reasons the ACE (Ardour community effects) plugins have no official custom GUI, and we asked 3rd parties to provide one instead. Ben at Harrison was the only one who volunteered to take up that task, and provide freeware UIs for ACE-EQ, ACE-Compressor and ACE-Delay.


I’ll only pay if it’s free software.