Neumann.Berlin KH 810 - Page 33

KH 810/870 | 31
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 L
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 K = 100 dB
Setting of switch
SUBWOOFER GAIN | OUTPUT
LEVEL K = 114 dB
-12 dB 88 dB SPL 102 dB SPL
-10 dB 90 dB SPL 104 dB SPL
-8 dB 92 dB SPL 106 dB SPL
-6 dB 94 dB SPL 108 dB SPL
-4 dB 96 dB SPL 110 dB SPL
-2 dB 98 dB SPL 112 dB SPL
0 dB 100 dB SPL 114 dB SPL
+2 dB 102 dB SPL 116 dB SPL
The default setting is SUBWOOFER GAIN | INPUT GAIN L = “0 dB” and SUBWOOFER GAIN | OUTPUT
LEVEL K = “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 L and the switch SUBWOOFER GAIN |
OUTPUT LEVEL K, you can compensate for level dierences due to acoustical loading (see page 10)
and due to dierent 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810/870:
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 L
0 0 0 0
SettingSUBWOOFER GAIN |
OUTPUT LEVEL K
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
dierent for the same subwoofer type installed in dierent locations in the same room. Moving the
cabinet small distances, 50 cm (20”), can dramatically change the response therefore resulting in
dierent 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.
EN