Peter Verbeek - 2026-04-13

This is how the developer of Equalizer APO has implemented the Audio Processing Object. Commands in the config.txt are processed by the APO of Equalizer APO. I'm not sure if there's another way so unfortunately what you describe is it. But it does make it possible that other interfaces like my Peace equalizer one work. Also, for most VST2 plugins this method work fine, well accept for the UI showing what's going. So commenting on your list:

  1. For most plugins the backend is working. The plugin (UI) settings are all in a textual command given to the APO. However, any change in any command and the plugin in the APO is created again causing a sound delay and/or distortion. So yet another issue. When a plugin is 'large" then this delay/distortion can be awful (while dialing a rotary knob on the plugin for instance).
  2. For most plugins it does work. Users do use plugins to their satisfaction.
  3. If the UI reflects the sound, for instance showing the audio stream, then you're right. Also, you're right about what the user thinks: 1 plugin while there's 2 (the UI and the DSP).
  4. That's indeed a concern.
  5. Unfortunately there's another issue: The Windows Audio Service having very limit access to our computer causing a VST plugin in any APO like Equalizer APO not able to check its license. There are some workarounds for this which may or may not work for plugins.

As main supporter of Equalizer APO I try my hardest to explain how all things work. Especially on VST plugins of which the plugins and their developers aren't usually the issue. My goal is that a user isn't blaming the plugin developer but try the info and workarounds I'm giving to either get the plugin going or to try another one. Most Peace equalizer users don't even need and use plugins in the first place as this interface has so much features. How Equalizer APO is set up it's good practice to not using VST plugins. But have said that, it might be that the developer is making the APO more efficient in the future.