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Polk Audio MM1240
Mobile Monitor Series 12" subwoofer
Our take on the Polk Audio MM1240 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 MM1240 12" 4-ohm 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 solidly without distorting.
This sub is certified for marine use, and Polk includes corrosion-resistant stainless steel mounting hardware.
Priced per speaker
I've had this speaker for over a year now and it is by far the best speaker I have ever owned. I stuffed it behind the seat of my 97 crew cab powerstroke in a sealed box matched up with a polk amp and it packs a big punch without giving up any space in the cab. A+++
What's in the Box:
- One 12" Single 4-ohm voice coil subwoofer
- Foam gasket
- 8 Mounting screws
- 8 Speed-clips
- Owner's Manual
- Product Registration Information sheet
- 12" 4-ohm subwoofer
- 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
- peak power handling: 800 watts
- frequency response: 22-200 Hz
- sensitivity: 92 dB
- top-mount depth: 4-11/16"
- sealed box volume: 0.88 cubic feet
- ported box volume: 1.58 cubic feet
- warranty: 1 year
- Our 60-day money-back guarantee
Polk Audio MM1240 Reviews
Average Customer Review(s):
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Features and Specs
|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||No|
92 dB at 1 watt
|Frequency Response||22 - 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.
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?
Quite possibly the best shallow sub out there for the value and 425 watts rms 22hz freq. Response and 92 dB sensitivity [ Bill Feb 22, 2017 ]
I have a pair of MM1540's in a sealed enclosure powered by a Soundstream 1000 watt monoblock amplifier. They really need more power than that. They also aren't as quick responding as I had hoped. I used to have 4 of the original 10" Mobile Monitors. I am hoping that these 12's will give me the low end that I want with a quicker response than the 15's. The 15's will be used with my home theater setup and get an amplifier pushing at least 2000 watts. [ Frank Dec 04, 2016 ]
2 questions already asked
It would prob be too big you might want to go with the 8" version of this sub or go with one in each saddlebag [ Scott Feb 17, 2017 ]