Equalizer APO - 3D SoundFx is a powerful audio processing app for Windows that brings precision equalization, immersive spatial audio, measured headphone correction, dynamic processing, and unified volume control together in one streamlined experience. Whether you're listening to music, gaming, watching movies, or fine-tuning your headphones, Equalizer APO - 3D SoundFx gives you the Swiss army tools to shape your listening experience the way you want.