FineTune
FineTune, a macOS menu bar app to control volume for each app
...It fills a gap in macOS audio control by providing more advanced routing and audio shaping capabilities than the default system controls, making it useful for power users, audio professionals, and anyone needing precise management of their sound environment. Through a clean, minimal interface accessible from the menu bar, FineTune lets users isolate and balance application volumes, assign specific outputs (like headphones versus speakers), and tweak equalization to enhance or tailor audio based on content or personal preference. Its integration into the OS workflow means that these adjustments persist across sessions and respect the user’s choices without requiring constant interaction with deeper system settings.