Higher latency with standalone app compared to VST3 plugin - bug or expected behavior?


So far I was using MIDI GUITAR 3 as a VST3 plugin within Ableton Live to control other VST3 synthesizers. Today I tested the standalone app and used it as MIDI input in Ableton Live. Surprisingly this leads to a higher latency than running it as a VST3 plugin. Both when playing in realtime and when comparing the recorded audio output of the third party VST3 synthesizer. Is this expected behavior? Or should the standalone app used as MIDI input in the DAW result in lower latency?

Signal path 1: Guitar → RME Babyface Pro FS → MIDI GUITAR 3 → Ableton Live → U-He Zebra (VST3)
Signal path 2: Guitar → RME Babyface Pro FS → Ableton Live → MIDI GUITAR 3 (VST3) → U-He Zebra (VST3)

The signal path via the standalone app had a 6 ms higher latency. All good like that or is this a bug that should be reported?

Equipment involved:
MacBook Pro, 13 inch, 2019
2,4 GHz Quad-Core Intel Core i5
macOS 13.5.2
Ableton Live 12.0.1
RME Babyface Pro FS

Thank you for reporting!

So, in both paths you sent the signal into Live(?). That is not really standalone. Path 1 send into Live via virtual MIDI, which could cause the 6ms.

The fastest path would be this:

Standalone path: Guitar → RME Babyface Pro FS → MIDI GUITAR 3 APP (U-He Zebra hosted inside MG3)

Thank you for clarifying this! I tried the standalone app to be able to select “All MIDI in” as a source in Ableton Live and use MIDI GUITAR 3 together with my other MIDI controllers as one unified MIDI stream. But this is not “standalone” use indeed and the additional latency for virtual MIDI makes sense. I’ll stick to the VST3 plugin then.