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5. CROSSOVER SETTINGS
5.1 ADJUSTMENT OF LOWPASS FILTER
To drive the active subwoofer system, the integrated electronic crossover always operates
in lowpass mode. The RN110A features a variable lowpass filter from 80Hz to 200Hz.
You can set an appropriate lowpass crossover frequency.
For this purpose, open the input gain control – the knob should point to "noon" – so you can
hear the subwoofer playing. Ideally, the low-pass cut-off frequency should be set between
80 to 200 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 lowend heavy!
5.2 ADJUSTMENT OF INPUT SENSITIVITY
To reach a maximum noise-free dynamic headroom from each individual head unit/active
subwoofer combination, it is important to set the respective input gain controls correctly. The
input level settings determine the actual signal-to-noise ratio, and they are also responsible
for obtaining the maximum distortion-free SPL (sound pressure level) from your specific
setup.
Turn-on your head-unit and set the volume control to approximately 3/4 of full volume,
while playing a dynamic track from a CD. Slowly increase the GAIN adjustment control of
the input of the RN110A.
Turn up the GAIN control knob until you can just about hear distorted bass sounds.
5.3 ADJUSTMENT OF PHASE SWITCH
The phase function of your RODEK RN110A can be set with the corresponding knob. The
phase-shift control enables you to match the acoustical phase relations of subwoofer and
the speaker system playing in the front doors, either a component or a coaxial system.
The target is that both speaker systems, normally separated by aprox. 3m of distance are
playing acoustically "in-phase" at the driver's seat location. A good match of the acoustical
phase between subwoofer and the system in the front doors will give you the impression of
bass sounds coming from a place in front of you.
The second advantage is, that the upper bass region - i.e. where the sound waves radiated
by the subwoofer and the kickbass or front door mounted component system is crossing
over – will sound considerably more precise and tight. This phase adjustment
can only be determined by ear, there is no rule of thumb to find a good match, and you will
definitely need somebody to help you. To judge the effect of the phase-shift adjustment,
you must sit in the driver's seat, and somebody must adjust the phase shift control until the
sound reproduction in the bass region is best.
5.4 BASS BOOST CONTROL
With the BASS BOOST control potentiometer you can add more output in the 60Hz region.
Please note, that this is a matter of taste. If you are not sure, leave this potentiometer fully
closed, i.e. rotated counter-clockwise.
