CXA1842S Datasheet, PDF (6/8 Pages) Sony Corporation – 3-Mode Surround and Vocal Cancellation

CXA1842S
Description of Functions
(1) Simulated Stereo
The sum of the L and R signals is input to the Simulated Stereo* (hereafter S.S) block, and a simulated
stereo signal is generated.
(2) Surround A (matrix surround)
The difference of the L and R signals is raised in level by the VCA (maximum 18 dB (typ.)), and is added
to the raw signal.
(3) Surround B
The difference of the L and R signals is raised in level by the VCA (maximum 18 dB (typ.)), is input to the
S.S block, and is then added to the raw signal.
(4) Pass
The L and R signals are output without modification.
(5) Vocal Cancellation
The difference of the L and R signals is input to the S.S block after first passing through the AGC circuit,
and is then output to L and R. In contrast with conventional products, the vocal cancel signal (L-R signal)
is raised in level by the VCA (max. 12 dB typ.), and low frequency part is enhanced, to prevent reduction in
the acoustic pressure level when vocal cancellation is ON.
* Simulated Stereo circuit:
Phases in the audio band are divided into two separate orthogonal channels and treated as L+R and L-R
signals, and are added and subtracted to produce simulated L and R signals. All-pass network.
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