Patent ID: 7536021

Claim:
An apparatus including a programmable processor or a semi-custom or full-custom dedicated processor, or one or more programmable logic devices, said apparatus for creating, utilizing a pair of oppositely opposed headphones, the sensation of a sound source being spatially distant from the area between said pair of headphones, said apparatus comprising: (a) a set of audio input terminals configured to accept a set of audio inputs representing audio signals each being projected from an idealized sound source located at a respective spatial location relative to an idealized listener, the set of audio inputs including at least a left audio input and a right audio input; (b) a first mixing matrix means interconnected to said audio terminals and one or more feedback inputs and configured to output a first predetermined combination of said audio inputs and said one or more feedback inputs as intermediate output signals and to output a sum of said audio inputs; (c) a filter system including: (i) one or more filters to filter said intermediate output signals and to output filtered intermediate output signals to account for the direct response of a room, and; (ii) one or more filters for feedback response filtering said sum and to output said feedback inputs to account for a non-directional approximation to the reverberant response of the room, wherein said feedback inputs are non-directional such that the filtered intermediate output signals include filtered direct response signals and filtered reverberant signals that also account for the direct response, wherein said feedback inputs are non-directional; and (d) a second matrix mixing means combining said filtered intermediate output signals to produce left and right channel stereo outputs.