Dolby Headphone

Dolby Headphone is a technology developed by Lake Technology (Australia), that later sold marketing rights to Dolby Laboratories, sometimes referred to as Mobile Surround, which creates a virtual surround sound environment in real-time using any set of two channel stereo headphones. It takes as input either a 5.1 or a 7.1 channel signal, a Dolby Pro Logic II encoded 2 channel signal (from which 5 or 7 channels can be derived) or a stereo 2 channel signal. It sends as output a 2 channel stereo signal that includes audio cues intended to place the input channels in a simulated virtual soundstage.

Dolby Headphone is incorporated into the audio decoders packaged with surround headphones including:

Dolby Headphone is supported by various netbooks, including the Lenovo IdeaPad S10-2 and the Acer Aspire One. Asus Xonar soundcards also have Dolby Headphone support, including Asus Xonar models: D1, D2/PM, DX, D2X, DG, HDAV1, ST, STX, Xense and U3. PowerDVD Ultra 9 also supports Dolby Headphone when certain options are set in the "Settings" menu but PowerDVD is not marketed as an official product of Dolby Headphone.

Several Nokia smartphones such as the Nokia N9 officially support Dolby Headphone, and the technology is also supported in the new version of the Nokia Belle Feature Pack 1. The functionality is either pre-installed or is available as an update for the Nokia 603, 700, 701 and 808 Pureview, and is included on many models in the Lumia series including the 810, 820, 920 and 1020.

Head-related transfer functions (HRTFs) are used to generate positional audio cues in the two channel output signal. A finite impulse response (FIR) filter is used to process the audio with lower latency.

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