Patent ID: 7558393

Claim:
A system for producing an output sound field that is representative of an input sound field, comprising: a microphone array for receiving the input sound field and producing therefrom a microphone signal (“P in ”) representative of the input sound field wherein P in comprises B-format channels, an FL (front left) channel, and an FR (front right) channel; an encoder for producing an encoded signal (“S.sub.out”) from P.sub.in using a transformation matrix S, such that S.sub.out=*P.sub.in wherein S out comprises an ITU-compatible six channel signal; a decoder for producing a decoded signal (“P out ”) from S out wherein P out comprises B-format channels, an FL channel, and an FR channel; and a plurality of speakers for producing the output sound field from P out , wherein S is the matrix comprising the quantities: s (L, FL) s (L, FR) S (L, W) s (L, X) s (L, Y) s (L, ) s (R, FL) s (R, FR) s (R, W) s (R, X) s (R, Y) s (R, Z) s (C, FL) s (C, FR) s (C, W) s (C, X) s (C, Y) s (C, Z) s (SC, FL) s (SC, FR) s (SC, W) s (SC, X) s (SC, Y) s (SC, Z) s (SL, FL) s (SL, FR) s (SL, W) s (SL, X) s (SL, Y) s (SL, Z) s (SR, FL) s (SF, FR) s (SR, W) s (SR, X) s (SR, Y) s (SR, Z) wherein: L represents a left speaker channel for an ITU-compatible six channel signal; R represents a right speaker channel for an ITU-compatible six channel signal; C represents a center speaker channel for an ITU-compatible six channel signal; SC represents a surround center speaker channel for an ITU-compatible six channel signal; SL represents a surround left speaker channel for an ITU-compatible six channel signal; SR represents a surround right speaker channel for an ITU-compatible six channel signal; FL represents the front left speaker channel; FR represents the front right speaker channel; W represents a B-format channel; X represents a B-format channel; Y represents a B-format channel; Z represents a B-format channel; and wherein s(α,β) represents a transformation quantity relating the respective α and β channels.