No, FFmpeg for Audacity does not automatically open when you want to open a large file in Audacity. FFmpeg is a separate program that needs to be installed and configured properly in order for Audacity to use it for handling certain file formats. You may need to manually specify the path to the FFmpeg executable in Audacity's preferences or settings. Additionally, FFmpeg provides command-line tools that can be used independently for various audio and video file operations.
