Samsung DVD-807K, Service Manual, Page: 94 / 165

Circuit Descriptions
Samsung Electronics 7-29
Fig. 7-46 2 Channel down mixing
The switch operations are carried out by AIC17(14053) in case of 2 Channel down mixing
and SUB WOOFER speaker using.
Table 7-47 Down mixing output table
7-7-2(c) Karaoke
Siganl input from the mike enters into the initial phase as it becomes somewhat amplified as well as subjected to
microphone volume control (At that moment, excessive input triggers Mute function-KQ1, KQ2).
The audio signals after passing through the volume control and the echo processed signals of the same audio
data are combined for sending it out.
On the other hand, if mikes have not been inserted, the 5th pin of each of MIC1 and MIC2 and KQ3 base will trig-
ger 'H,' bringing on the mute function on the Karaoke Board.
Hence, it can preserve the quality of the main board as usual.
7-7-3 CD/VCD audio output
The audio of CD and VIDEO-CD bypasses the signals of SIC7(TC9420F) in BIC8,9 and BIC1 A/V decoder and
outputs them to DATA0. Also they are outputted in stereo 2 channel(L/R channel) via D/A conversion and filtering
of AIC1(PCM1720/AK4324).
FRONT L CH. (AIC4 PIN 1 OUTPUT)
FRONT R CH. (AIC5 PIN 1 OUTPUT)
CENTER CH.
-4.5dB
LOW PASS FILTER
L CH
R CH
AIC 17(MC14053)
15 Y
Y1 1
Y0 2
X1 13
14 X
FRONT L CH
SUB WOOFER
FRONT R CH
REAR L CH.
REAR R CH.
AIC17(10,11PIN) A,B
H
DOWN MIXING THE USER USES SUB WOOFER
L
AIC17(PIN 2)
Y0
(PIN2 SUB WOOFER OUTPUT)
OUTPUT
AIC17(PIN 13,1)
X1, Y1
MIXED L/R OUPUT