M61508FP

REJ03F0203-0201 Rev.2.01 Mar 31, 2008

Page 21 of 24

2. Loudness Gain Setting

Lower Figure is Structure of Loudness Circuit.

+

–

+

–

+

–

10

VOLUME 1

LOUDNESS VOLUME

LOUDNESS

FILTER

(Gv = 0 dB)

VIN

V1

V2

R

R

R

R

VOUT

Output Voltage (VOUT) of Setting Structure of Upper Figure

It is noted as Volume 1 Output Voltage = V1, Loudness Filter Output Voltage = V2, VOUT and Gv (Boost quantity) is

given at the lower formula

VOUT = V1 + V2 (Vrms)

VOUT = 31.6 m + 100 m

= 131.6 mVrms

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

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

From: Volume1, Loudness Volume attenuation quantity

Become: V1 = 31.6 mVrms

V2 = 100 mVrms

If the sub situdes the equation for the upper formula,

the following equation is given,

Gv = 20 log

– (–30 dB)

(31.6 m + 100 m)

1

=12.4 dB is obtained

Gv

(V1 + V2)

VIN

– (Volume 1 attenuation quantity) (dB)

Gv = 20 log

Volume 1 = –30 dB

Frequency (Hz)

In the item, the Loudness Gain Setting example is shown, when Volume 1 fixation and doing the Loudness Volume

variably. Please refer to Plan.