Neumann.Berlin KH 805, Operating Manual

Page: 28 / 33

KH 805 |
27
Acoustical
output level
Depending on the setting of the potentiometer SUBWOOFER GAIN | INPUT GAIN
L
and the switch
SUBWOOFER GAIN | OUTPUT LEVEL
K
— and referred to an input signal level of 0 dBu — the following
acoustical output levels can be obtained:
Setting of potentiometer
SUBWOOFER GAIN |
INPUT GAIN
J
Acoustic output level [dB SPL] of the subwoofer at 1 m
when input signal level is 0 dBu
Setting of switch SUBWOOFER GAIN | OUTPUT LEVEL
H
94 dB 100 dB 108 dB 114 dB
-
12 dB 82 dB SPL 88 dB SPL 96 dB SPL 102 dB SPL
-
10 dB 84 dB SPL 90 dB SPL 98 dB SPL 104 dB SPL
-
8 dB 86 dB SPL 92 dB SPL 100 dB SPL 106 dB SPL
-
6 dB 88 dB SPL 94 dB SPL 102 dB SPL 108 dB SPL
- 4 dB 90 dB SPL 96 dB SPL 104 dB SPL 110 dB SPL
- 2 dB 92 dB SPL 98 dB SPL 106 dB SPL 112 dB SPL
0 dB 94 dB SPL 100 dB SPL 108 dB SPL 114 dB SPL
+ 2 dB 96 dB SPL 102 dB SPL 110 dB SPL 116 dB SPL
The default setting is SUBWOOFER GAIN | INPUT GAIN
J
= “0 dB” and SUBWOOFER GAIN | OUTPUT
LEVEL
H
= “100 dB SPL at 1 m”, which corresponds to a sound pressure level of 100 dB SPL mea-
sured at a distance of 1 m, when the input signal has a level of 0 dBu .
Using the potentiometer SUBWOOFER GAIN | INPUT GAIN
J
and the switch SUBWOOFER GAIN |
OUTPUT LEVEL
H
, you can compensate for level differences due to acoustical loading (see page 9)
and due to different distances of the subwoofers and loudspeakers from the listening position .
Examples of how to calculate sound pressure levels as a function of the input signal levels and input
and output levels of the KH 805:
Absolute voltage level of
input signal
0 dBu
(0 .775 V)
+4 dBu
(1 .23 V)
+6 dBu
(1 .55 V)
+16 dBu
(4 .89 V)
Setting SUBWOOFER GAIN |
INPUT GAIN
J
0 0 0 0
Setting SUBWOOFER GAIN |
OUTPUT LEVEL
H
100 100 100 100
Measured output level in dB
SPL at 1 m
100 104 106 116
Acoustical
response
Neumann subwoofers are designed to have a flat pass band magnitude response in anechoic condi-
tions when all the acoustical controls are set to 0 dB . When a subwoofer is installed into a listening
environment the response changes and thus should be corrected back to a flat response . It is there-
fore expected that the acoustical controls will need adjustment to improve the in-situ response of the
subwoofer . The acoustical controls’ settings depend on the subwoofer’s location and will probably be
different for the same subwoofer type installed in different locations in the same room . Moving the
cabinet small distances, 50 cm (20"), can dramatically change the response therefore resulting in dif-
ferent acoustical control settings .
Graphs of acoustical measurements conducted in anechoic conditions at a distance 1 m can be found
at the end of this operating manual . Color versions of these graphs can be found on the corresponding
product pages at www .neumann .com .