Neumann.Berlin KH 805, Руководство по эксплуатации

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KH 805 |
17
X
Check the frequency response at the listening position using your acoustical measurement
system:
• In case of acoustical loading in the low frequency range at the listening position, turn
the potentiometer LOW CUT
9
to the left . This reduces the output level of the subwoofer
towards lower frequencies .
• Use the parametric equalizer
0
to compensate for further nonlinearities in the frequency
response below 120 Hz caused by room modes and/or reflections .
X
Measure the subwoofer’s sound pressure level at the listening position .
X
Adjust the sound pressure level of the subwoofer so that the level of the frequency response
of the subwoofer below 80 Hz corresponds to the level of the frequency response of the
loudspeakers above 80 Hz .
• To do so, use the potentiometer SUBWOOFER GAIN | INPUT GAIN
J
and the switch
S UBWOOFER GAIN | OUTPUT LEVEL
H
. Make sure that the input signal is not too high .
X
Set the phase using the left switch SUBWOOFER PHASE
L
. Values from - 180 º to - 315 º can
be obtained by setting the right switch SUBWOOFER PHASE
M
to “–180 º ” and by adding the
set value of the left switch SUBWOOFER PHASE
L
.
Example : To obtain a phase shift of –270 º , set the right switch SUBWOOFER PHASE
M
to
“–180 º ” and the left switch SUBWOOFER PHASE
L
to “–90 º ”
X
Set the left switch SUBWOOFER PHASE
L
in combination with the right switch SUBWOOFER
PHASE
M
to values of 0 º , - 45 º , - 90 º , - 135 º , - 180 º , - 225 º , - 270 º , and - 315 º , until you have
found the setting that gives the lowest sound pressure level at the listening position at the
cut-off frequency of 80 Hz (180º phase shift between subwoofer and loudspeaker, maximum
level cancelation) .
X
Set the right switch SUBWOOFER PHASE
M
to the opposite position . The phase shift between
loudspeaker and subwoofer is now 0
º
. Check your subwoofer’s sound pressure level again
and, if necessary, readjust it so that it corresponds to the sound pressure level of the
l oudspeakers .
Your system is now completely acoustically calibrated .
Note that any change of the low cut and parametric EQ influences the crossover
phase . Therefore, the phase and the level need to be recalibrated after changing the
low cut or parametric EQ settings .
Calibration using Neumann test signals
X
Download the Neumann test signals and the instructions for use (PDF file, in English) from
the KH 805 product page at www .neumann .com .
X
Follow the steps described there .
Calibration using music signals and an 80 Hz test signal
X
Adjust the settings for the sound pressure level and the frequency response as described
above .
X
Calibrate the acoustical phase using an 80 Hz test signal . Check the settings of the sound
pressure level and frequency response by means of music signals you are familiar with .
• Connect the left front loudspeaker to the socket OUTPUT | LEFT
D
.
• Set the switch BASS MANAGEMENT
F
to “ACTIVE” .
• Play an 80 Hz test tone from your source into the audio input INPUT | LEFT
C
so that the
subwoofer and left loudspeaker are playing the tone .
• Set the rotary switch SUBWOOFER PHASE
L
in combination with the switch SUBWOOFER
PHASE
M
to values of 0 º ,
-
45 º ,
-
90 º ,
-
135 º ,
-
180 º ,
-
225 º ,
-
270 º , and
-
315 º , until you
have found the setting that gives the lowest sound pressure level at the listening position
at the cut-off frequency of 80 Hz (180
º phase shift between subwoofer and loudspeaker,
maximum level cancelation) .
• Switch off the test signal at the source .
• Set the switch SUBWOOFER PHASE
M
to the opposite position .
The phase shift between loudspeaker and subwoofer is now 0 º .
Calibrating the
subwoofer level
Calibrating the
phase