VST3 (midi) and JUCE


After a week of compiling rewriting and cursing I came to the conclusion that VST3 (midi side) doesn’t like JUCE at all. eg try midi.clear() which should clear the input midibuffer doesn’t scratch VST3 - it just outputs the input . Try the JUCE Arpeggiator example … VST3 is completely muted… vst2.4 and AU work though


follow up - seems to eliviate problem a bit
1 tick : isSynth
2 make audio outputs or just : AudioProcessor () in constructor
still doesn’t clear input buffer


I’m also having midi problems with VST3 -> MPE VST3 issue


follow up 2nd
after testing a dozen midi processors I give up . VST3 definitely does not obey
midi.swap or midi.clear(). It just mirrors the input in any case .


I am seeing the same thing in the JUCE Plug-in Host. Thanks for clearing this up for me.

So does this mean that there is no way to stop an incoming note_on from being output?


Hi there,
I am having an issue with VST3 also.
I can’t seem to build VST2 plugins anymore there are build errors in xcode.
I battled with a plugin all day trying to troubleshoot.
After reading this thread I tried it as an .au and it works fine.
It seems like the midi juce classes aren’t doing what they should in VST3
I am just using basic stuff like

MidiBuffer processedMidi;
for(MidiBuffer::Iterator i (midiMessages); i.getNextEvent(m, time);)


Soul lang rant #2 , midi VST3 issues

I noticed that recently (03.12.2018), Steinberg updated their VST3 SDK to 3.6.12, introducing some changes that should make MIDI plugins easier to implement.

Interfaces Changes:

  • New Steinberg::Vst::LegacyMIDICCOutEvent: allowing a Plug-in to generate MIDI CC as output event.
  • New Steinberg::Vst::IMidiLearn (Plug-in): allow a Plug-in to get the currently live playing MIDI CC to implement custom MIDI learning.

Did JUCE integrate these new features already or is planning to? Anybody knows how far are we from being able to release VST3 MIDI plugins with the JUCE platform?

I’m not in a hurry, I have a license to release VST2 plugins, but I dread the moment where users will start asking for a VST3 version of my plugins.


Are there any VST3 MIDI plugin available and how do they work in DAW’s?
Is it possible to add MIDI insert plugins into a slot before synth plugins like in Logic with AU MIDI FX plugins? Or is track to track routing required like in Ableton Live?

  • Jussi