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Adjustments
Adjustments after replacing PCB03, Main PCB
Read out the adjustment position of the old potentiometers, R301 & R312, and
set the new potentiometers to the same position.
Adjustments of bass/treble levels
Each loudspeaker is individually adjusted from production to ensure optimal stereo
perspective. When replacing a speaker unit or PCB03, Main PCB, bass/treble levels
have to be adjusted. On the back of the new speaker unit will be printed a rated
value for the sensitivity of the particular unit. The rated value is stated in dB and
have to be converted to a mechanical position of the two potentiometers by using
table 1 and fig.1.
After replacing a speaker unit
- Adjust treble level by means of (R301) and the bass level by means of (R312).
These two potentiometer are accessible via the two holes in the socket well, see
fig. 1.
- Adjusts according to the drawing and table 1. Only the potentiometer of the
replaced unit have to be adjusted.
WARNING: Do under no circumstances adjust the level of a unit that has not been
replaced!
Table 1
‘‘Clock position’’
(The new position
of the
potentiometer)
Bass deviation ±dB
Treble deviation ±dB
0830
+3.1
+3.9
0900
+2.7
+3.3
1000
+1.8
+2.2
1100
+0.9
+1.1
1200
0.0
0.0
0100
-0.9
-1.1
0200
-1.8
-2.2
0300
-2.7
-3.3
0330
-3.1
-3.9
Fig.1
LINE
L
R
1
2
POWER
LINK
W
T
12
3
1
2
11
10
9
3.1 Adjustments
Summary of Contents for Beolab 4000 MKII 6642
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