VST3 vs VST2 Automation Smoothness


I don’t know if it’s a bug, but the automation is different between vst2 and vst3 plugins. VST2 is smoother to me. VST3 jumps, it look like has less steps.

video here : https://vimeo.com/750630237/4191907010
Above VST2
below VST3

Can some one explain it ?

I’m on OSX C12.

Can you show us the automation curves?
Does this happen also with other plugins?

This might also only be a visual thing inside the fabfilter plugins.
If it happens only with fabfilter plugins, I’d contact them directly.

It did on all VST3 plugins probably. For example StudioEQ and Channel EQ sohmehow jumps too.
I don’t have many plugins to test it.

Question is, if its graphical issue or VST3 automation has lower ressolution (it look like VST3 has lower ressolution)

For example in Ableton live did not happened… its smooth.

Yeah looks like it. Even if it is probably hard to hear a difference, but still.
If it happens for all plugins, I’d add the “issue” tag to the topic.

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I think this is only a graphical “issue”, the result is the same, a simple null test is enough to confirm that.

Some plugins do the same thing, some are in between, and some others are super smooth.
I believe this in an option in the VST3 code to reduce the refreshing interval of the GUI controls when automation is being read, in order to save resources when the plugin window is open.
It’s up to the plugin manufacturer to set it as they wish.

It’s like the hold function when you tweak controls when automation is in Read mode. Most plugins snaps back to the automation value as soon as you release the click, but a few have set a higher value, for example 500 ms.


I don’t know if this topic was just about the “graphical” problem or the actual audio, but anyway, if that concerns audio, this was addressed in another topic, starting from that post.
In any case, the graphical thing is totally unrelated to the audio part, those are two different things.