faust2juce -double creates buggy VST

[adrienbourgeois]

How to reproduce:

1. Create dummy plugin simple_gain.dsp:

declare name "simple_gain";
import("stdfaust.lib");

process = *(ba.db2linear(-1));

2. Convert to juce project running:

faust2juce -double simple_gain.dsp

3. Open projuce, go to settings and select "VST3" as plugin formats
4. Open Xcode (macOS)
5. Compile (compilation succeeds)
6. Load the VST into any DAW (I'm using Ableton Live)
7. Load the plugin on a track playing some sound
8. In real time, things are working fine
9. Bounce: the bounce will be full of distortion
10. After that the plugin is in a broken state and needs to be removed from the session

If I take the exact same steps without passing the -double option, things are working fine.

Note that I'm on a Macbook pro M3.

Any help on this would be appreciated! Cheers

[sletz]

• how do you activate Bounce in Ableton Live?
• have you tried with other DAWs ?

[adrienbourgeois]

how do you activate Bounce in Ableton Live?

A bounce is simply an export of the session. The key part is that during a bounce the DAW switches from real time to offline and, from what I understand, sends bigger blocks to the VST.

have you tried with other DAWs ?

A friend of mine tried on Cubase and experienced the same issue.

I forgot to mention:

Faust version: 2.83.1
I have also pushed the process file here in case that's useful: https://github.com/adrienbourgeois/JuseSimpleGainPlugin/blob/main/FaustPluginProcessor.cpp

[sletz]

Can you possibly test https://github.com/grame-cncm/faust/tree/juce-export-fix branch ? (I've raised double/float adaptation buffers to 16384 frames)

[sletz]

@adrienbourgeois does juce-export-fix fix the problem ?

[adrienbourgeois]

Hi @sletz , sorry I was off grid for the whole of last week. I’ll eagerly try your branch tomorrow and will keep you posted. Thank you so much for looking into this.

[adrienbourgeois]

hi @sletz , unfortunately it didn't work. Here is what I did:

• pulled juce-export-fix branch
• successfully built the project running: make & sudo make install
• replaced the faust binary from the .dmg 2.83.1 I had installed prior with the one I built
• Rebuilt my simple_gain VST with the steps mentioned above but using the faust2juce I had just built: /Users/adrienbourgeois/code/faust/tools/faust2appls/faust2juce -double simple_gain.dsp
• then followed same steps from step 3 mentioned in my first message

And I am still facing the issue :(

update:
Actually sudo make install copied the binaries into /usr/local/bin so I can confirm I am definitely using binaries built from juce-export-fix branch:

adrienbourgeois@mac simple_gain % type faust
faust is /usr/local/bin/faust
adrienbourgeois@mac simple_gain % ll /usr/local/bin/faust
-rwxr-xr-x@ 1 root  wheel  5306968 12 Mar 15:54 /usr/local/bin/faust
adrienbourgeois@mac simple_gain % type faust2juce
faust2juce is /usr/local/bin/faust2juce
adrienbourgeois@mac simple_gain % ll /usr/local/bin/faust2juce
-rwxr-xr-x@ 1 root  wheel  10627 12 Mar 15:46 /usr/local/bin/faust2juce

and can confirmed the fix is not working.

[sletz]

Does it happens also with other export format than VST3 ?

[adrienbourgeois]

I have tried to compile into an AUv2 and the issue is NOT happening, which is great! However I would still need to compile to a VST as my plugin will need to support all DAWs and not all of them support AU.

VSTv2 would work for me but unfortunately the compilation fails when trying to build a VSTv2 because I don't have the VSTv2 SDK installed on my machine and the VSTv2 SDK is nowhere to be found on the internet since it was deprecated by Steinberg. I'd love to be proven wrong on this one.

After a quick search on the internet I found this issue iPlug2/iPlug2#388 where someone faced the same build errors when trying to compile a VSTv2:

The "missing" files are part of the VST2 SDK which is not available any longer. Steinberg deprecated it last year and if you do not have a license from Steinberg you are not allowed to build any VST2 plugin.

In summary:

• Issue is not happening on AUv2
• A fix for VST3 would still be very much appreciated.