Polk Audio MM10, MM12 Optimal Crossover Setting, Inverting Phase, Safe Limits Of Operation

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Permanent mounting is not only the safest installation, but usually produces the best sound quality. This Custom Enclosure is heavy and has a smooth surface finish, and can slide around in a trunk during aggressive driving or a collision if unsecured. This could result in damage to the enclosure or the car.

Use either the mounting brackets provided, or, if you do not wish to drill into your car body, use a couple of large, well-placed pieces of industrial-strength hook & loop fastener attached to the enclosure and the trunk surface. Polk Audio takes no responsibility for damage done to car structures if this product is not secured.

Once you have found the best location, use the enclosed mounting brackets to secure the subwoofer enclosure to the body of your car. Use the screws included only to attach the bracket to the subwoofer enclosure. Attach the brackets to the bottom of the enclosure only. No screws are provided for car-body mounting purposes due to various types of trunk mate- rials. The installer needs to choose the appropriate screw type and length for the intended trunk-mounting application. The installer must be careful when drilling into the car struc- ture not to damage any important elements (fuel lines, electrical conduits, you know; stuff like that). Polk Audio takes no responsibility for damage done to car structures when securing this product. If you are at all uncertain about the best and safest way to install your subwoofer enclosure, consult your local Polk Audio dealer or professional installer.

Break It In

Your Polk/MOMO Custom Enclosed Subwoofer will achieve even greater performance once it is thoroughly broken-in. To break in your new custom enclosed sub, 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 Polk/MOMO

Custom Enclosed Subwoofers

With one subwoofer we recommend an amplifier with a power rating of at least 200- Watts (x 1 in bridged mode) to sufficiently drive this woofer. 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 90 Hz as a good starting point. This is an optimal crossover setting on most vehicles.

Inverting Phase

Depending on the placement of your custom 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/MOMO Custom Enclosed Subwoofer is 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).

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.

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Bass Blocker

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or Capacitor

Radio

 

Speaker

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4 P O L K / M O M O : C H A M P I O N S H I P P E R F O R M A N C E

 

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N E R ’ S M a N U a L Put It In Your Trunk Bass Master Commands YouWiring Diagrams For Polk/MOMO Custom Enclosed Subwoofers Important Information About Warranty & InstallationOptimal Crossover Setting Inverting PhaseSafe Limits Of Operation MM10 MM12 Polk/MOMO Custom Enclosed Subwoofer SpecificationsMetro Drive Baltimore, Maryland 800