Polk Audio GNX104-4 - Manual (Page 7)

LOW FREQUENCY CUT-OFF FOR MID-RANGE SPEAKERS
IN SYSTEMS WITH SUBWOOFERS
Now that you have a subwoofer in your system, you may want to decrease the amount of bass
going to your mid-range speakers. This will get you better mid-range sound and increase the power
handling. There are two ways to roll off the bass before it gets to your mid-range speakers. One way is
to use a “bass blocker,” a capacitor placed in series with the speaker input. Bass blockers are installed
in series, one end connected with the positive lead from your amplifier and the other end connected
to the positive lead of each of your speakers. Bass blocker capacitors (200 microfarad @ 100volts,
non-polarized) are available at any RadioShack or parts supply house. The other route is to use
an electronic crossover device that allows filtering below 100Hz or so. Find these devices at your
authorized Polk Audio dealer.
TECHNICAL ASSISTANCE OR SERVICE “NO SOUND?”
If, after following these hookup and installation directions, you experience difficulty, please
double-check all wire connections.
Make certain your electronic equipment is operating correctly by hooking up another speaker to the
speaker output. For example, if you are not getting sound from the left channel speaker, connect the
right channel speaker to the left output. If you still get no sound from that side, the problem is in your
amp or source electronics. Should you isolate the problem to the speaker, contact the authorized Polk
Audio dealer where you bought your speakers. Authorized Polk Audio dealers are the best source for
advice and assistance.
Polk Audio’s Customer Service Department is available from 9am–6pm, EST, Monday through Friday,
at 800-377-7655 (US & Can only, outside the US call 410-358-3600). Please do not hesitate to call us if
you have questions about your speaker system.
You will find additional information, informative articles, manual updates and cool
stuff to buy that has “Polk Audio” all over it by visiting www.polkaudio.com.
7 For more info and accessories, visit www.polkaudio.com
BREAK IT IN.
GNX Subwoofers will achieve even greater performance once they are thoroughly broken-in.
To break in your new GNX Subs, play 20 to 30 hours of music at moderate levels.
GET MORE INFORMATION ONLINE AT POLK UNIVERSITY:
http://www.polkaudio.com/car/faqad/index.php
AMPLIFIER POWER REQUIREMENTS FOR GNX SUBWOOFERS
Your Subwoofers will work well with a variety of electronic components. As little as 50 watts per channel
will deliver adequate listening levels in most cars. If you have a noisy car or intend to play your system
at loud listening levels, more power is necessary to achieve the best performance. More power is always
better. Consult your Polk Audio dealer for specific recommendations.
OPTIMAL CROSSOVER SETTING
We recommend using an active crossover with a 12 to 18dB per octave low pass filter slope, and
setting it to an initial setting of 80 to 90Hz as a good starting point. This is an optimal crossover
setting on most vehicles.
INVERTING PHASE
Depending on the placement of your subwoofer enclosure and associated components, it may be
necessary to invert the phase of one or another of your system’s connections in order to gain better
subwoofer/mid-range blending. Inverting the phase simply means switching the positive connections
with the negative connections at the amplifier. If you choose to do this, invert the phase of only one
set of speakers (either your mains, or your subs, never both).
SAFE LIMITS OF OPERATION
Your Polk GNX Subwoofers are made with the highest quality materials for years of trouble-free
performance. However, damage to loudspeakers can occur when an amplifier, regardless of its
wattage, is made to play at higher listening levels than its power can clearly produce (usually
beyond the “1 to 2 o’clock” position on the volume control). This results in very high levels of
audible distortion, originating in the amplifier, which adds a harsh, gritty sound to the music.
Contrary to popular belief, a speaker is more likely to be damaged by trying to get too much
volume from a low-powered amp than from a high-powered one. Hear distortion? Turn it down.
Contact Polk Customer Service 800-377-7655 (9am–6pm, EST, Monday through Friday).
6 Contact Polk Customer Service: 800-377-7655 [email protected]
Radio/Amp Speaker
Bass blocker
or capacitor
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