Dolby Laboratories CP65 - Manual (Page 56)

Action Indication Step
No.
5-34
B-Chain Alignment Procedures
e. Surround Equalization Alignment (Cat. No. 441)
3
5
4
Dolby
n-sync surr gain
Q
on
present
signal
gnd
gain
bass
Q
mid freq
cut
treble
tp
bass
Q
freq mid
cut
treble
gain mag/dig
opt gain
off
auto freq
cut
tp
present
signal
Subwoofer
Left Surround
Right Surround
Cat. No.
441
Dolby
n-sync surr gain
Q
on
present
signal
gnd
gain
bass
Q
mid freq
cut
treble
tp
bass
Q
freq mid
cut
treble
gain mag/dig opt gain
off
auto freq
cut
tp
present
signal
Subwoofer
Left Surround
Right Surround
Cat. No.
441
Dolby
n-sync surr gain
Q
on
present signal
gnd
gain
bass
Q
mid freq
cut
treble
tp
bass
Q
freq mid
cut
treble
gain mag/dig
opt gain
off
auto freq
cut
tp
present signal
Subwoofer
Left Surround
Right Surround
Cat. No.
441
.05 .1 .2 .4 .8 1.6 3.15 6.3 12.5 kHz
dB
–10
+5
0
–5
+10
NOTE
.05 .1 .2 .4 .8 1.6 3.15 6.3 12.5 kHz
dB
–10
+5
0
–5
+10
B-Chain Alignment Procedures
Notes
5-35
e. Surround Equalization Alignment (Cat. No. 441)
Adjust the Left Surround bass control on the Cat. No. 441 card for as flat as possible
low frequency response on the RTA. Use caution when adjusting the bass control; many
surround loudspeaker systems are deficient in their low frequency response. Attempts to
boost the output of such system beyond their capabilities simply wastes amplifier power
and can result in distortion and possibly damage to the surround loudspeakers.
Turn the Cut control fully counterclockwise and note the position of the notch produced
by the equalizer.
Adjust the Left Surround treble control to its mid point, so that it provides neither cut
nor boost.
Adjust the mid frequency controls as follows: Turn the Cut control fully clockwise (CW).
Set the Q and freq controls to their mid positions.
Note the position of the center of the highest frequency peak in the 350 Hz to 3 kHz region
on the analyzer screen.