OSS 3D 2.3b7 - Real-time enhancements of sound in OS X. (Shareware): "
OSS 3D utilizes state of art DSP technology allowing addition of bass spatialization, 3D surround and various other real-time enhancements of the sound played through your system.
OSS 3D greatly improves audio quality in movies and music throughout all of the OS X applications. It provides non-destructive spatial expansions similar to Spatializer or QSound, with additional functionality of Speaker Resonance Correction, Virtual Subwoofer, Automatic Gain Control, Brainwave synthesis, High Frequency Restoration, Center channel control, and more. Also included a studio quality N-band equalizer with built-in peak limiter.
MacUpdate - Universal Binary - http://www.macupdate.com/macintel.php