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Polk Audio MM521

5-1/4" 2-way car speakers

9 Reviews

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Item # 107MM521

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Overview

Our take on the Polk Audio MM521

Polk Audio continues its tradition of making brilliant-sounding speakers in stylishly designed packages — their Mobile Monitor (MM) Series speakers look great and sound even better. Each speaker utilizes an extra-strong, extra-small neodymium magnet that saves space and weight, allowing these speakers to fit into more places in more vehicles while still delivering a full sound with lots of kick. Their lightweight carbon composite frames provide strong, flex-free support for the speakers' motor assemblies.

Polk Audio continues its tradition of making brilliant-sounding speakers in stylishly designed packages — their Mobile Monitor (MM) Series speakers look great and sound even better. Each speaker utilizes an extra-strong, extra-small neodymium magnet that saves space and weight, allowing these speakers to fit into more places in more vehicles while still delivering a full sound with lots of kick. Their lightweight carbon composite frames provide strong, flex-free support for the speakers' motor assemblies.

The Polk MM521 5-1/4" speakers feature honeycomb-textured woven glass fiber composite woofer cones that respond very quickly for a clean, crisp, and powerful sound. Large voice coils — over an inch in diameter — give the speaker high power-handling capability and extended reliability.

1" silk dome tweeters add a sweet high end that blends perfectly with the low notes so your music stays in harmonic balance, from the electric bass all the way on up to the cymbals. Swivel mounts on the tweeters allow you to aim the high notes to produce a superior soundstage in your car.

Important Note: These Polk speakers use a low-impedance design to pull more power safely from your car stereo or amplifier. This design is compatible with virtually all factory and aftermarket stereos.

Priced per pair

Couldn't be happier. Product installed easily, sound awesome and look even better.

Anonymous, Indiana

What's in the Box:

  • Two 2-way 5.25" speakers
  • 2 Grilles
  • 2 Passive crossovers
  • 8 Hex-head screws
  • 4 Phillips-head screws
  • 8 Speed clips
  • Owner's Manual
  • Product Registration information sheet

Product Highlights:

  • 5-1/4" 2-way speakers (pair)
  • woven honeycomb glass fiber composite woofer cone with butyl rubber surround
  • 1" silk composite dome tweeter with swivel mount
  • certified for marine use
  • 2.7-ohm impedance for extra power (compatible with virtually all factory or aftermarket car stereos)
  • power range: 15-90 watts RMS (200 watts peak power)
  • frequency response: 50-25,000 Hz
  • sensitivity: 92 dB @ 2.83 V
  • top-mount depth: 2-3/8"
  • warranty: 1 year
  • Our 60-day money-back guarantee
Reviews

Polk Audio MM521 Reviews

Average Customer Review(s):

(9 Reviews)
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Details

Hands-on research

Features and Specs

General
Speaker Size 5 1/4
Design 2-way
Tweeter Design 1" Dome
Tweeter Composition Silk/polymer composite
Woofer Composition Glass Fiber Composite
Woofer Surround Butyl Rubber
Parts Warranty 1 Year
Labor Warranty 1 Year
Specifications
Sensitivity (1W at 1 meter) 92
Sensitivity at 2.83 volts N/A
Frequency Response 50 - 25k Hz
Minimum RMS Wattage 15
Maximum RMS Wattage 90
Peak Power Handling (Watts) 200
Impedance (Ohms) 3
Top-mount Depth (Inches) 2 1/2
Bottom-mount Depth (Inches) N/A
Cutout Diameter or Length (inches) 4 11/16

Product Research

Features

Dynamic Balance: Dynamic Balance is a proprietary Polk Audio technology using laser imaging to determine what combination of speaker materials create the least amount of resonance. Eliminating resonance in speakers results in a wide, smooth response and low distortion.

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.

Woofer Cones: Woven glass composite cones feature tremendous stiffness-to-mass ratio. Lower mass means faster transients and finer detail.

Butyl Rubber Surrounds: For a smoother response and improved durability, the woofers use butyl rubber surrounds. The airtight rubber surrounds stand up to moisture, sunlight and extreme temperatures while allowing long excursion linear motion and years of reliable use.

Silk/Polymer Composite Swivel Tweeters: The 1" liquid-cooled, silk/polymer composite tweeters provide clear, detailed highs. The 15-degree swivel tweeter housings deliver direct, detailed imaging; instantly adjustable through the grille.

Neodymium Magnets: The speaker's neodymium magnets offer exceptional strength to performance ratio and is extremely lightweight.

Large Diameter Voice Coils: Large diameter, 30mm voice coils increase the speaker's reliability and power handling capacity.

Carbon Composite Basket: The speaker's carbon composite basket is lightweight and will not flex during music audio peaks.

Crossover: The speaker comes supplied with two separate 2-way crossovers; one for each speaker. Each crossover input 36" lead is terminated with tinned wire, and the two 20" output leads (one for the woofer and one for the tweeter) are terminated with female quick-slides. The positive woofer lead has a 0.250" female quick-slide and the negative woofer lead has a 0.187" female quick-slide. The positive tweeter lead has a 0.187" female quick-slide and the negative tweeter lead has a 0.110" female quick-slide. These quick-slides connect directly to the woofer and tweeter terminals on each speaker. The separate 2-way crossover network sends the appropriate frequencies to each driver for cleaner sound and better imaging. Dimensions: width = 3.515", height = 1.015", depth = 2.645"

Mounting: The speaker itself has 4 mounting holes for a standard 5-1/4" application.

Grilles: Strong ABS plastic grilles are included. These computer optimized grilles feature a spoke-wheel design.

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.

Our Product Research Team

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