The Dolby USB adapter that comes packaged with the GameCom 777 headset features two Dolby algorithms: Dolby Pro Logic II and Dolby Headphone. All audio comes into the adapter as 2 channel stereo via USB from the computer. That audio is then passed off to Dolby Pro Logic II. Dolby Pro Logic II takes the Left and Right channel content and using the directional cues that occur naturally in stereo creates a five-channel surround output representing the left, right, center, left surround and right surround channels. This information is then passed off to Dolby Headphone which emulates the 5 channels over a standard 2 channel stereo headset.