ELECTRIC

MITSUBISHI

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1 4 )

M65854FP

MITSUBISHI SOUND PROCESSOR ICs

KARAOKE

S E R I E S

DIGITAL ECHO WITH MICROPHONE MIXING CIRCUIT

1 1

(6) Input and output LPF for the digital echo

The input and output LPF for the digital echo are configured as shown.

figure below.

24k

24k

24k

C2:1000pF

C1:4700pF

Input

Output

13

14

15

The accuracy of the internal resistance of the IC is approximately ±30%

Cut-off frequency(fc) is given as follows.

Quality factor (Q) is given by the following equation for long echo.

fc=

1

C1 X C2

Q=

C1

C2

1

3

=

1

2

π X 24k X 4700pF X 1000pF

3.1KHz

0.72

(Figure of 0.7 is recommended)

(5)ALC level diagram

-30

-20

-10

0

+2

10

-50 -40 -30 -20 -10

MICROPHONE AMPLIFIER GAIN SETTIG=47dB

ALC OPERATING VOLTAGE SETTING RANGE

Vo(dBV)

Vi(dBV)

-60

-70

2

π X 24k X