Matrix (sound recording)

In sound recording, a matrix can refer to a disc in the early stages of processing a record for mass production; see mastering and pressing process discussion at gramophone record. Matrix can also refer to the encoding of several channels of audio into fewer channels to be decoded back into several channels later.

Contents 1 SQ Matrix ("Surround Quadraphonic", "Stereo Quadraphonic", CBS SQ) 2 QS Matrix ("Quadraphonic Stereo", QS) 3 Ambisonics UHJ coding matrix 4 Dolby Surround Matrix 5 Dolby Pro Logic Matrix 6 Dolby Pro Logic II Matrix 7 See also

SQ Matrix ("Surround Quadraphonic", "Stereo Quadraphonic", CBS SQ)

Encoding Matrix	Left Front	Right Front	Left Back	Right Back
Left Total	1.0	0.0	j0.7	k0.7
Right Total	0.0	1.0	k0.7	j0.7

j = + 90° phase-shift , k = - 90° phase-shift

QS Matrix ("Quadraphonic Stereo", QS)

Encoding Matrix	Left Front	Right Front	Left Back	Right Back
Left Total	0.92	0.38	j0.92	j0.38
Right Total	0.38	0.92	k0.38	k0.92

j = + 90° phase-shift , k = - 90° phase-shift

Ambisonics UHJ coding matrix

Encoding Matrix	W (pressure signal)	X (front-back information)	Y (left-right information)
Left Total	0.470 + k0.171	0.093 + j0.255	+0.328
Right Total	0.470 + j0.171	0.093 + k0.255	-0.328

j = + 90° phase-shift , k = - 90° phase-shift

Dolby Surround Matrix

Encoding Matrix	Left	Right	Center	Surround
Left Total	1.000	0.000	0.707	j0.707
Right Total	0.000	1.000	0.707	k0.707

j = + 90° phase-shift , k = - 90° phase-shift

Dolby Pro Logic Matrix

The encoding matix is the same as for Dolby Surround; only the Pro Logic decoder differs.

Encoding Matrix	Left	Right	Center	Surround
Left Total	1.000	0.000	0.707	j0.707
Right Total	0.000	1.000	0.707	k0.707

j = + 90° phase-shift , k = - 90° phase-shift ///00

Dolby Pro Logic II Matrix

Encoding Matrix	Left	Right	Center	Rear Left	Rear Right
Left Total	1.000	0.000	0.707	j0.8165	j0.5774
Right Total	0.000	1.000	0.707	k0.5774	k0.8165

j = + 90° phase-shift , k = - 90° phase-shift

See also

• Ambisonics
• Quadraphonic
• Surround sound