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Polk Audio db521

5-1/4" 2-way car speakers

87 Reviews | 4 questions - 6 answers

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Polk Audio DB 522




Our take on the Polk Audio db521

Good music becomes great when you hear it through Polk's db Series car speakers. Polk engineers use laser imaging to determine the ideal combination of speaker materials and design to eliminate distortion. The resulting technology produces speakers with smooth frequency response, sharp detail, and the ability to play music at high volumes without strain.

Polk Audio db521

Stylish, durable ABS grilles

Give your music new life

Good music becomes great when you hear it through Polk's db Series car speakers. Polk engineers use laser imaging to determine the ideal combination of speaker materials and design to eliminate distortion. The resulting technology produces speakers with smooth frequency response, sharp detail, and the ability to play music at high volumes without strain.

Durable and dynamic

Polk's db521 speakers feature 5-1/4" woofers made from a polymer/mica composite and durable rubber surrounds that won't fall apart under stress from heat, moisture, or time. Liquid-cooled 3/4" silk/polymer dome tweeters use powerful Neodymium magnets to deliver precise high-frequency reproduction, enveloping you in bright musical detail. And you can even pivot the tweeters, aiming them at your ears for improved stereo imaging. The built-in two-way crossovers keep the high and low frequencies flowing to the proper drivers for seamless, efficient audio.

The stainless steel mounting hardware is built to last, while the muscular ABS grilles will look great in your car's interior. Whether you've got a factory radio or an aftermarket stereo, these efficient speakers will spice up your daily drive.

Priced per pair

Product Highlights:

  • 5-1/4" 2-way cars speakers (pair)
  • marine certified — recommended for fresh water and powersports applications
  • Dynamic Balance polymer/mica composite woofer with butyl rubber surround
  • 3/4" pivoting liquid-cooled silk/polymer composite dome tweeter
  • Neodymium tweeter magnet
  • Kapton voice coil
  • built-in 2-way crossover network
  • ABS wheel-design grilles
  • stainless steel mounting hardware
  • power range: 4-45 watts RMS (135 watts peak power)
  • frequency response: 60-22,000 Hz
  • sensitivity: 93 dB
  • top-mount depth: 2-5/16"
  • warranty: 1 year
  • Our 60-day money-back guarantee

What's in the Box:

  • Two 2-way speakers
  • 2 Grilles
  • 8 Self-tapping screws (length=1")
  • 8 Speed clips
  • Owner's Manual (English/ Spanish/ French/ German/ Italian/ Portuguese)
  • Online registration sheet

Featured Video

excellent sound reproduction. A head unit will power this speakers, but a small amp really makes them come to life. they can handle the power of heart throbbing beats and crystal clear highs. Excellent speakers and excellent sound.

tim, Oklahoma City, OK


Polk Audio db521 Reviews

Average Customer Review(s):

(87 Reviews)
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Hands-on research

Features and Specs

Speaker Size 5 1/4
Design 2-way
Tweeter Design 3/4" Dome
Impedance (Ohms) 4
Tweeter Composition Silk/Polymer composite
Woofer Composition Polymer/Mica composite
Woofer Surround Butyl rubber
Parts Warranty 1 Year
Labor Warranty 1 Year
Sensitivity (1W at 1 meter) 93
Sensitivity at 2.83 volts N/A
Frequency Response 60 - 22k Hz
Minimum RMS Wattage 4
Maximum RMS Wattage 45
Peak Power Handling (Watts) 135
Top-mount Depth (Inches) 2 5/16
Bottom-mount Depth (Inches) N/A
Cutout Diameter or Length (inches) 4 3/4

Product Research


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.

Woofer Cones: Each speaker features a Dynamic Balance polymer/mica composite mineral-filled cone. The cones are stiff and lightweight for big sound and low distortion.

Butyl Rubber Surrounds: For a smoother response and improved durability, the woofers use butyl rubber surrounds.

Kapton Voice Coil Former: The low-mass two-layer 25mm Kapton Voice Coil former is lightweight for high sound output. Kapton's high melting temperature (725°F) ensures high power handling and longer reliability.

Silk/Polymer Composite Tweeters: The 3/4" liquid-cooled, silk/polymer composite tweeters provide clear, detailed highs. The tweeters use neodymium magnets.

Pivoting Tweeter: The tweeter pivots, allowing you to aim it toward your listening position for better imaging.

2-way Crossover Network: The built-in 2-way crossover network sends the appropriate frequencies to each driver for cleaner sound and better imaging.

Flat Spider: The speaker utilizes a flat spider for faster, longer excursion linear motion.

Pole Plate Heat Sink: The speaker's pole plate heat sink promotes better heat dissipation for superior power handling and reliability.

Woven Leads: The speaker features flexible woven leads sewn directly into the spider for greater reliability.

Basket: The speaker is housed in a solid, acoustically inert stamped steel basket finished in rustproof gun metal gray.

Grilles: Strong ABS plastic grilles are included. These computer optimized grilles are based on exclusive MOMO designs.

Marine Certification: Polk speakers are marine certified, making them a good choice for boats in fresh water, convertibles, motorcycles, ATVs, and other applications where the speaker might get wet. Because they have coated steel baskets and the terminals and crossover components are not covered, we do not recommend using them in salt water environments.

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.

Staff Reviews

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Customer Q&A

4 questions already asked

Thanks for your question. On the product page "Accessories" tab you'll see a section for speaker baffles. These will work for you: [ Kenny  Jul 27, 2016 ]  Staff
For additional details on fit or installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on if this will fit and what you will need for an installation in your vehicle. [ Kenny  May 23, 2016 ]  Staff
Sorry I didn't use the grills I mounted the speakers behind panels and thru the grills in the trash. [ KEITH  Feb 06, 2015 ]
Hey Jason, I don't know the exact dimension of the grill, but it is definitely wider than the speaker itself as it shows. I would guess somewhere in the 5-1/2" to 6" range. I had to leave them off when I installed them in my 2003 Jeep Wrangler as they would not fit in the OEM enclosure with the grills installed. If you need exact dimensions, let me know and I'll measure the ones that I put back in the box. Good luck! Tim [ TIMOTHY  Feb 06, 2015 ]
Right at 6 inches. [ Mandy  Feb 06, 2015 ]
Thanks for question Chad. For product recommendation on amp to match your speakers I'd recommend reaching out to an Advisor by phone or chat. They will be able to help you find an amp that will fit your system and your budget. [ Jeff  Dec 11, 2013 ]  Staff

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