Matrix decoder
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Matrix decoder is an audio technology where a finite number of discrete audio channels (e.g. 2) are decoded into a larger number of channels on play back (e.g. 5). The channels are generally, but not always, arranged for decoding by an encoder, and decoded for playback by a decoder.
The notation for matrix encoding consists of the number of discrete audio channels separated by a colon from the number of decoded channels. For example, two discrete channels decoded to four-channels would be notated:
2:4
Five discrete channels decoded to six channels would be notated:
5:6
Many matrix encoders take advantage of the Haas effect, as well as audio cues inherent in the source channels.
The various encoding matrixes are described below.
Contents |
[edit] SQ Matrix (2:4, "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 = + 90º phase-shift , k = - 90º phase-shift
[edit] QS Matrix (2:4, "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 = + 90º phase-shift , k = - 90º phase-shift
[edit] Ambisonics UHJ coding matrix (2:3)
| 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 = + 90º phase-shift , k = - 90º phase-shift
[edit] Dolby Surround Surround Matrix (2:4)
| 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 = + 90º phase-shift , k = - 90º phase-shift
[edit] Dolby Pro Logic Matrix (2:4)
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 = + 90º phase-shift , k = - 90º phase-shift
[edit] Dolby Pro Logic II Matrix (2:5)
| 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 = + 90º phase-shift , k = - 90º phase-shift
