Patent ID: 8867750

Claim:
A surround sound virtualization method for producing output signals for reproduction by a pair of physical speakers at physical locations relative to a listener, where none of the physical locations is a location in a set of rear source locations, said method including the steps of: (a) in response to input audio signals indicative of sound from the rear source locations, generating surround signals useful for driving the speakers at the physical locations to emit sound that the listener perceives as emitting from said rear source locations, including by performing dynamic range compression on the input audio signals; and (b) generating the output signals in response to the surround signals and at least one other input audio signal, each said other input audio signal indicative of sound from a respective front source location, such that the output signals are useful for driving the speakers at the physical locations to emit sound that the listener perceives as emitting from the rear source locations and from each said front source location, wherein step (a) includes a step of generating the surround signals including by performing decorrelation on the input audio signals, wherein the dynamic range compression is performed by nonlinear amplification of the input audio signals so as to improve audibility of the sound from the rear source locations relative to the sound from each said front location during reproduction of the output signals by the speakers at the physical locations, and wherein at least one of the dynamic range compression or the decorrelation is performed so as to provide improved localization of the sound from the rear source locations, relative to sound from at least one said front source location, during reproduction of the output signals by the speakers at the physical locations.