D-61508-98-C

ELECTRIC

MITSUBISHI

( /22)

THE ELECTRIC VOLUME of BUILD-IN NON FADER VOLUME with TONE CONTROL

MITSUBISHI SOUND PROCESSOR ICs

M61508FP

LOUDNESS

FILTER

(Gv=0dB)

2 LOUDNESS GAIN SETTING

Lower Figure is Structure of Loudness Circuit.

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VOLUME 1

LOUDNESS VOLUME

R

R

R

R

VOUT

VIN

V1

V2

Output Volutage (VOUT) of Setting Structure of Upper Figure

It is noted as Volume1Output Volutage = V1, Loudness Filter Output Voltage = V2,

VOUT and Gv (Boost quantity) is given at the lower formula

Gv = 20 log

ex.) VIN = 1Vrms/60Hz,Volume1= - 30dB,

Output Volutage and Boost Quantity of 60Hz of Loudness Volume = -20dB setting

From : Volume1,Loudness Volume attenuation quantity

Become : V1 = 31.6mVrms

V2 = 100mVrms

If the subsitudes the equation for the upper formula,

the following equation is given :

(V1 + V2)

VIN

- (Volume 1 attenuation quantity) (dB)

VOUT = V1 + V2 (Vrms)

VOUT = 31.6m + 100m

In the item,the Loudness Gain Setting example is shown, when Volume1 fixation and

doing the Loudness Volume variably. Please refer to Plan.

Gv = 20 log

(31.6m + 100m)

1

- (-30dB)

= 12.4dB is obtained.

=131.6mVrms

Frequency (Hz)

Gv

Volume 1= -30dB

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