8-inch dual voice coil mobile audio/marine subwoofer
Designed to Perform
Introducing the new MM840 high performance 8-inch subwoofer. Great for big bass without taking up much space. As a result of 3 years of Polk research and development, the new MM systems have been designed to offer unparalleled sound quality with exceptional fit to meet virtually any application. Borrowing technology from our flagship SR Series, the MM Series offers exceptional value for the price. Through the use of high-tech carbon composite baskets, powerful neodymium motor structures using oversized voice coils, and state-of-the-art woven glass composite cones, we offer high-end audio performance normally found only in the most expensive loudspeaker systems.
With 250 Watts continuous/500 Watts peak power handling, the MM840 is recommended for small sealed (.35 cubic foot) enclosures.
New 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 (51mm) and polyamide former withstands the most rigorous use while maintaining extremely low distortion for bass punch and output.
Heavy duty input terminals accommodate speaker wire up to 8 AWG or twisted pairs of 12 AWG.
Advanced carbon composite basket based on the spokes of a wheel is lightweight, will not flex during peaks and looks great! Don’t be afraid to show off the back of your woofer.
Klippel optimized components 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.
Available matching grille complement the wheel spoke design.
Single voice coil configuration (MM840) also available.
All Polk products are made using the best materials and the most advanced manufacturing techniques. They pass the industry’s most exhaustive quality tests, including drop testing, extreme signal response and UV & salt exposure testing. Polk loudspeakers are built to perform for a lifetime.
|Type||Dynamic Balance poly composite woofer|
|Total Frequency Response||26-200Hz|
|Nominal Impedance||Dual 4 ohms|
|Driver Diameter||1 1/2" (3.81cm)|
Thiele / Small Parameters
|Resonant Frequency||43 Hz|
|SD||35.65 sq in/230 sq cm|
|VAS||.55 cu ft/15.8 L|
|Cut-Out Diameter||7 1/8" (18.10cm)|
|Driver Mounting Depth|
|Top Mount||4 1/8" (10.48cm)|
|Bottom Mount||4 11/16" (11.91cm)|
|Unit of Measure||each|
|Speaker Warranty||1 year parts and labor (original purchaser)|
Specifications, dimensions and features subject to change without notice. For more information call us at 1-800-377-7655 (USA and Canada). Outside of North America call +1 (410) 358-3600.
1 reviews with an average of 5Write your own review
by M C R Evans, April 8, 2009127 out of 188 people found this review helpful.
Small size (8 inches) doesn't dominate all the space in the rear of my Bronco. Polk web site also had plenty of plans to build any size/type of enclosure you desire. Speaker/Box combination covers a wide audio range up to 1,000hz (used my signal generator). Matches well to the PA400.1 monoblock amplifier (mounted right on the side of the box that I built [MM2084]). I recommend this path to anyone handy with basic carpentry (to build the box) and wiring skills. And if you have a friend to do this for you . . .
Only been using it for 3 weeks (the one in the Bronco) and 1 week (the one in the house). Haven't experienced any downside thus far.
I was looking for a smaller subwoofer with a wider range. The polk site included plans for subwoofer boxes. I opted for a ported box with a wide range (MM2084) and got the response desired. Connected the speaker to a PA400.1 which mounted right on the side of the subwoofer box I built. Response is perfect without overbearing boominess I hear from other passing cars and trucks. I made the mistake of connecting the completed speaker/box to my home entertainment system prior to installing it in my truck. It was so much better than that other subwoofer that I had to go out and buy another speaker and build another box for in house use. Thus I actually have two of these speakers!! Adds a lot to the overall listening experience of CD's & DVD's!!!
MM840 DVC Media
MM840 DVC Literature
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