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4. CROSSOVER SETTINGS
Now you can set an appropriate lowpass crossover fre-
quency. For this purpose, open the input gain control -
the arrow of the knob should point to "noon" - so you can
hear the subwoofer playing. Ideally, the low-pass cut-off
frequency should be set between 50 to 90 Hz - and this
setting has to be entirely determined by ear. Try to find
lowpass crossover frequency setting, that gives you a
"full-bodied" bass reproduction with enough impact in
the upper bass range.
Note: If the lowpass crossover frequency is set too low,
the sound will have a tendency to sound extremely soft
and low-end heavy!
Now you can adjust the subsonic-highpass, if you wish
to squeeze out the most (max-dB) of your subwoofer
system. Turn the highpass frequency control up, to a
point where you can hear that the bass reproduction
starts to get "thinner". The subsonic highpass frequency
should be set to a value between 20 to maximum 50 Hz.
4.2.4 ADJUSTING INPUT SENSITIVITY
To reach a maximum noise-free dynamic headroom from
each individual head unit/amplifier/speaker combinati-
on, it is important to set the respective input gain con-
trols correctly. The input level settings determine the ac-
tual signal-to-noise ratio, and they are also responsible
for obtaining the maximum distortion-free SPL (sound
pressure level) from your specific setup.
4.2.2 BANDPASS FOR KICKBASS
SYSTEMS
If you intend to operate a kickbass loudspeaker system in
the front doors of your vehicle, you must select two cross-
over frequencies at the active crossover of your RODEK
amplifier. The operation mode must be set to bandpass.
The bandpass filter contains a highpass (10 - 400Hz) with
a cascaded lowpass (30 - 400Hz) filter. The lowpass
crossover frequency point is usually set at a frequency
that equals at least twice the value of the highpass
crossover frequency setting. The lowpass filter is mostly
set a little lower, than the highpass crossover frequency
setting of the satellite channel.
Kickbass speaker system, front door mounted,
recommended bandpass frequencies
16 cm Kickbass Speaker System 80 - 110 Hz Highpass
200 - 250 Hz Lowpass
4.2.3 BANDPASS FOR SUBWOOFER
SYSTEMS
To drive a subwoofer system, the integrated electronic
crossover must also operate in bandpass mode. Before
you attempt to adjust the lowpass crossover frequency,
you must first turn the (subsonic)highpass frequency
control counterclockwise to its lowest position at 10 Hz.
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