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Polk Audio MM1240D
Mobile Monitor Series 12" sub with dual 4-ohm voice coils
Our take on the Polk Audio MM1240D by Crutchfield's Gabrielle Thorndyke
Polk Audio's Mobile Monitor Series subwoofers bring out superior performance from lighter materials, so you'll get the impact you want without the extra weight of a conventional system. Advanced engineering and optimized components reproduce your sound with uncompromising accuracy, for low end that is rich and clear.
The MM1240D 12" dual voice coil subwoofer handles up to 425 watts RMS. A copper voice coil and neodymium magnet motor drives the polymer cone with exceptional efficiency. The carbon composite basket features a "wagon wheel" design that resists flexing during heavy excursion, so your sub hits sub hits solidly without distorting. The dual 4-ohm voice coils offer options for wiring a multi-sub system or drawing maximum power from your mono amplifier.
This sub is certified for marine use, and Polk includes corrosion-resistant stainless steel mounting hardware.
Priced per speaker
Great sub for the price. Perfect addition to our boat. Great sound, highly recommed.
Anonymous, Columbus, OH
What's in the Box:
- One 12" Dual 4-ohm voice coil subwoofer
- Foam gasket
- 8 Mounting screws
- 8 Speed-clips
- Owner's Manual
- Product Registration Information sheet
- 12" subwoofer with dual 4-ohm voice coils
- polymer cone with butyl rubber surround
- carbon composite basket
- certified for marine use
- optional matching grille complements the basket design
- power range: 100-425 watts RMS (212 watts RMS per coil)
- peak power handling: 800 watts
- frequency response: 27-200 Hz
- sensitivity: 88 dB
- top-mount depth: 4-11/16"
- sealed box volume: 0.88 cubic feet
- warranty: 1 year
- Our 60-day money-back guarantee
Polk Audio MM1240D Reviews
Average Customer Review(s):
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Features and Specs
|Impedance||2 ohms or 8 ohms|
|Surround Material||Butyl Rubber|
|Ideal Sealed Box Volume (cubic feet)||0.88|
|Ideal Ported Box Volume (cubic feet)||1.58|
|Port diameter (inches)||N/A|
|Port length (inches)||N/A|
|Dual Voice Coil||Yes|
88 dB at 1 watt
|Frequency Response||27 - 200 Hz|
|RMS Power Range (Watts)||100-425|
|Peak Power Handling (Watts)||800|
|Top Mount Depth (inches)||4 11/16|
|Bottom Mount Depth (inches)||5 1/4|
|Cutout Diameter or Length (inches)||11 1/16|
|Parts Warranty||1 Year|
|Labor Warranty||1 Year|
Klippel Optimized: Using a state-of-the-art Klippel Distortion Analyzer, Polk engineers were able to optimize the woofer's motor structure, voice coil alignment and suspension for the best possible performance, even at extreme listening levels.
Polymer Woofer Cone with Butyl Rubber Surrounds: The Polymer Woofer Cones and Butyl Rubber Surrounds will not break down over time and will survive the rigors of harsh automotive environments.
High Temperature Copper Voice Coil (50mm) and Polyamide Former: High Temperature 50mm Copper Voice Coil and Polyamide Former withstand the most rigorous use while maintaining extremely low distortion for bass punch and output.
Dual 4-ohm Voice Coils: This woofer features dual 4-ohm voice coils that offer wiring flexibility. When the voice coils are wired in parallel, the woofer presents a 2-ohm load. When wired in series, the woofer presents an 8-ohm load.
Carbon Composite Basket: The woofer's carbon composite basket is lightweight and will not flex during music audio peaks.
Nickel Plated Heavy Duty Input Terminals: Nickel plated heavy duty input spring-post terminals accommodate speaker wire up to 8 AWG or twisted pairs of 12 AWG.
Preconditioning Period: Mobile Monitor subwoofers will achieve even greater performance once they are thoroughly broken in. To break in your new MM subwoofer, play 20 to 30 hours of music at moderate levels.
Marine Certified Woofer: Polk MM Series speakers are built to withstand exposure to moisture and UV rays, so they work well in boats and cars. They also include stainless mounting hardware for corrosion and rust resistance.
Recommended Sealed Box Volume: Polk recommends mounting this woofer in a sealed enclosure made out of 3/4" MDF with an internal volume of 0.88 cu/ft.
Recommended Ported Box Volume: Polk recommends a ported enclosure made out of 3/4" MDF with an ideal internal volume of 1.58 cu/ft using a slot port measuring 13.5" wide x 1.5" tall x 18.5" deep.
Our Product Research Team
At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.
Why did you buy this?
one of the best in the market [ bruno Feb 06, 2017 ]
It match all of my speakers that are currently in my boat as well as good power handling capabilities [ norman Aug 01, 2016 ]
This is the perfect sub for under rear truck seat installation without having to buy a shallow mount sub. [ Curtis Apr 29, 2016 ]
2 questions already asked
1 answer Can I mount this subwoofer and have the very back of it all the way against the back wall of the enclosure? If not how much of a gap do I need? Also with the sub mounted flat against enclosure with grill attached how far does it stick off the surface of the enclosure? [ Jessie Mar 09, 2017 ]
Ideally you'd want to leave some space between the back of the subwoofer and the enclosure in order to allow airflow to the coils and magnet; even as little as 0.5" of space can be helpful in that regard. The Polk MM1240D also has a mounting height of 0.9" without the grille. However, I'm afraid we don't have any mounting height specs listed when the grille is added. You may want to reach out to Polk directly in order to find that out--you can check their support website (https://www.polkaudio.com/support) or call them at 800-377-7655 for more info. [ Larry Mar 19, 2017 ] Staff
If you made your box 17 in wide and 18 inch long and 5 inch deep , the speaker is 4.5 deep, you would have .8845 cu.ft . displacement . [ STEVEN Mar 03, 2017 ]
Polk actually recommends .88 cu.ft. internal displacement. [ STEVEN Mar 03, 2017 ]
ITs specs are in the owners manual and available online for free [ bruno Mar 01, 2017 ]