Spectra is a system-wide equalizer for macOS. It sits between every app and your speakers or headphones, so one setting covers music, video, calls and games, with no virtual audio driver and nothing added to your Sound settings.
What separates it from other Mac EQs is measurement. Spectra plays pink noise through your speakers, listens through your iPhone over Continuity, and fits correction filters to what your room is actually doing. There is no measurement microphone to buy. A speaker measurement takes about 90 seconds and every output keeps its own calibration, Bluetooth included. For headphones it applies professional target curves in one click, with a full parametric layer on top.
Free tier, with a free account and no credit card: a 10-band system-wide graphic EQ. Base is $59 one time and adds the room measurement and correction, the headphone calibration library, a 5-band parametric layer, the spectrum analyzer, and the effects (Dynamic EQ, Sub Bass Extension, Prism:X Stage). Pro is $11.99/month, $99/year, or $179 one time, and adds unlimited parametric bands, calibration controls, bass management, a sweep trouble finder, deep effect settings, and saved presets.
Honest limitations: it requires macOS 26.2 or later. There is no per-app EQ, because the audio tap is device-scoped. There is no AutoEq file importer yet; the headphone library is curated instead. External audio interfaces are the least-tested path.
The system-audio layer is open source under MIT as CoreAudioTapKit on GitHub. Made by Spectra Audio. Notarized and signed. Not on the Mac App Store, because the system audio path needs entitlements the store does not grant.
Spectra Audio 
