Windows Default APOs

With Windows the audio driver does not provide digital audio system effects. All digital signal processing for creating system effects is provided by real-time in-process COM objects called system effects audio processing objects (APOs).

Windows provides an Enhancements tab with the Sound applet on the Control Panel for configuring these system effects. The APOs provided by default with Windows are shown in the following list.

Bass Boost

Bass Management

Enhanced Sound for Laptop Computers

Loudness Equalization DSP

Low Frequency Protection

Room Correction

Speaker Fill

Speaker Phantoming

Virtual Surround

Virtualized Surround Sound over Headphones