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Polk Audio db5251
5-1/4" component speaker system
Our take on the Polk Audio db5251 by Crutchfield's Leigh Schoettinger
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's versatile db5251 component speaker system features 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 1" silk/polymer dome tweeters use powerful Neodymium magnets to deliver precise high-frequency reproduction, enveloping you in bright musical detail. You can surface- or flush-mount the tweeters with the included swivel-mount cups. Just aim the tweeters so they broadcast toward your ears, creating a powerful stereo image.
External crossovers direct the right frequencies to the tweeters and woofers to maximize their performance, and their housings let you hide all wiring for a clean, professional look. These speakers feature stainless steel mounting hardware, plus muscular ABS grilles that will add a stylish touch to your car's interior. And Polk certifies their db Series speakers for marine applications, so they're a great choice for your boat, motorcycle, or ATV.
Installation note: You'll need a pair of our universal backstraps to install the tweeters in the factory locations.
Priced per system
i may have gotton wrong speakers
Scott, Katy, TX
What's in the Box:
- 2 Woofers
- 2 Grilles
- 2 Tweeters (each tweeter has attached 38" speaker leads)
- 2 Flush-mount cups
- 2 Metal flush-mount clamps
- 2 Surface-mount cups
- 2 Crossovers
- Four 39" lengths of speaker wire (each length of wire has female quick-slides on one end and tinned wire on the other end)
- 16 Self-tapping screws
- 10 Speed clips
- Owner's Manual (Eng/Span/Fren/Ger/Ita/Port)
- Online registration sheet
- component speaker system includes two 5-1/4" woofers, 2 tweeters, and 2 crossovers
- Dynamic Balance polymer/mica composite woofers with butyl rubber surrounds
- Kapton voice coils
- 1" liquid-cooled silk/polymer composite dome tweeters
- flush- and surface-mount swivel cups
- Neodymium tweeter magnets
- electronic tweeter protection circuits
- 2-way external crossover network (12 dB/octave, 4,000 Hz high- and low-pass)
- marine-certified for use in boats, convertibles, motorcycles, and ATVs
- ABS wheel-design grilles
- stainless steel mounting hardware
- power range: 10-100 watts RMS (250 watts peak power)
- frequency response: 53-23,000 Hz
- sensitivity: 93 dB
- top-mount depth: 2-5/16"
- warranty: 1 year
- Our 60-day money-back guarantee
Polk Audio db5251 Reviews
Average Customer Review(s):
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Features and Specs
|Speaker Size||5 1/4|
|Tweeter Design||1" Dome|
|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||53 - 23k Hz|
|Minimum RMS Wattage||10|
|Maximum RMS Wattage||100|
|Peak Power Handling (Watts)||250|
|Top-mount Depth (Inches)||2 5/16|
|Bottom-mount Depth (Inches)||N/A|
|Cutout Diameter or Length (inches)||4 3/4|
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 Formers: The low-mass 2-Layer 1" Kapton Voice Coil formers are lightweight for high sound output. Kapton's high melting temperature ensures high power handling and excellent reliability.Pole Plate Heat Sinks: The pole plate heat sinks promote better heat dissipation for superior power handling and reliability.
Silk/Polymer Composite Tweeters: The 1" liquid-cooled, silk/polymer composite tweeters provide clear, detailed highs.
Mounting: The supplied mounting cups allow you to surface- or flush-mount the tweeters. The tweeters swivel in the flush-mount housings, allowing you to adjust them for optimum imaging.
Tweeter Mounting Dimensions:
|Surface Mount||Flush Mount|
|Depth||0.825" (screw depth)||0.938"|
2-Way Crossovers: Each Butterworth outboard crossover features a 12dB/octave, 4000Hz high-pass network for the tweeter and a 12dB/octave, 4000Hz low-pass network for the woofer.
Tweeter Attenuation Switch: You can adjust the output of the tweeter to match a level appropriate to your vehicle or your system. On the end of crossover (opposite the terminals), the tweeter attenuation switch can be set to 0dB, -3dB, or +3dB.
Electronic Tweeter Protection Circuits: Each crossover has a built-in protection circuit that guards the tweeter against accidental damage from high power.
Crossover Connections: The crossover inputs and outputs are screw terminals. The crossover housing is vented, giving you a choice of hidden wire channels for easier, more professional-looking installs.
Mounting: There are two mounting holes in the base of each crossover.
Crossover Dimensions: L=5.029", W=3.072", H=1.075"
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.
Product reviews from the Crutchfield Labs
by Ken Nail, J.R. Stoffel
Learn about the features that make Polk Audio's db series car speakers a popular choice for improved sound.
Why did you buy this?
I LOVE these speakers in my previous vehicle. Buying them again!! [ Cliff Aug 29, 2016 ]
I am not a fanboy of any particular brand. I have used Polk before, and I am budget minded. I needed to replace the crumby speakers on my pontoon, and these fit the bill. The RMS was what I wanted, and it is marine rated. Eventually I will add a mono block with a sub, and a 4 channel amp to power these speakers. Until then, these should do the trick. Thank you, Crutchfield for making things a breeze! Tim in customer service was helpful, keep up the good work, man! Tim's Bio: http://www.crutchfield.com/Support/Bio.aspx?bio=136 [ Shane Jul 05, 2016 ]
Best choice for the money. [ D Jun 25, 2016 ]
Cause these speakers rock :) [ Doug Jun 11, 2016 ]
I have Polk in all my other cars their awesome Just buy them you're going to love them once you're in your car [ johnathan May 29, 2016 ]
Awesome sound, components, etc. [ SCOTT Apr 03, 2016 ]
Great price. I'm a fan of Polk home audio and their car audio blew me away. This is a great component system at a very fair price. If you get these get a sub. They don't truly shine until they shed off a the little low end onto a sub. Highly recommended. [ Messman Motorcy Mar 12, 2016 ]
Good Reviews, recommended by Conrad from Crutchfield. This is known as best budget component system. [ Dan Feb 29, 2016 ]
Good RMS [ R.TERESKO Feb 22, 2016 ]
Brand, and Price [ G E Feb 18, 2016 ]
These speakers are marine grade and will be going into a Jeep. Plus I wanted a component speaker. [ Ed Feb 07, 2016 ]
Our family likes polk car speakers. [ Kelly Feb 07, 2016 ]
I used polk speakers before, sale price and product features attracted me. [ Quamrul Jan 29, 2016 ]
good reviews, know brand. [ Sherri Jan 19, 2016 ]
On sale , great frequentcy response!!! [ Donald Jan 15, 2016 ]
Outstanding experience with Polk Audio speakers! [ ERIC Dec 21, 2015 ]
Expected Polk quality sound and construction [ James Dec 15, 2015 ]
Recommended fit to my vehicle and the reviews were great. I had Polk 6x9's in the past and they were superb so I think these should be even better. [ G Dec 07, 2015 ]
8 questions already asked
Hey Josh, I'm sorry to say I never bought an Alpine KTP-445U power pack. But, on the other hand db5251 sound great no matter what your using. I've used Rockford Fosgate and j.l.audio. worked great. Never had a problem. Good Luck, Eric S. [ Eric Jul 06, 2016 ]
I would get a amp with the same RMS so it's really clear at high volume. [ KERTTON Jul 06, 2016 ]
I don't know off hand, but you should find it under product specifications [ Roy Jul 02, 2016 ]
4 ohm, they are very good [ JAVIER Jul 01, 2016 ]
4 ohm [ Daniel Jul 01, 2016 ]
Per the online manual, the nominal impedance is 4 ohms [ Eric Jul 01, 2016 ]
Im currently using the Sound Ordinance M-4050, I works well but I didn't expect it to be so big! I should've spent the $50 extra to get the kenwood or maybe an alpine. Usually any big brand with 50 watts RMS and up for each channel should be good. Check your impedance values and make sure that they match up or else you could fry and amp. I think most should be matched already. [ David May 26, 2016 ]
Any 4 channel amp should be fine. I used a low power 4 channel, 2 channels bridged for my bazooka bass tube in the trunk (i had no where else to put it). I had a very small Z3 so much power was not necessary. Speakers sounded fine with only the head unit power also [ MIKE R May 26, 2016 ]
The power of a system is measured in watts for both amplifier output and speaker power handling. Keeping a good balance between these numbers will give you the best results. I recommend having your speaker's power handling equal to, or slightly over, the RMS/continuous power output of your amplifier. I honestly didn't power them with an amp. They sound really good when properly tuned on a decent head unit. [ John May 26, 2016 ]
The speakers come packaged with both surface & flush mount bracket options for the tweeters. You will find this information (as well as the mounting dimensions for each) by clicking the "Details" tab on the speaker's main webpage and scrolling down below the "Features & Specs" table. I hope that helps! My Bio: http://www.crutchfield.com/Support/Bio.aspx?bio=5 [ Ryan Jan 08, 2016 ] Staff
For 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. [ Krissy Jan 06, 2016 ] Staff
4 speakers total [ FRANKLIN E Dec 25, 2015 ]
Four; two low/mid range speakers and two tweeters/high range speakers, one each for left and right, with a crossover for each pair [ Robert Dec 23, 2015 ]
2 tweeters and 2 speakers [ BANCROFT Dec 22, 2015 ]
You will receive a total of (4) speakers, (2) tweeters and (2) 6 1/2 or 6 3/4) including the two component devices to drive both the front left, and front right or depending on where you install your speakers. I bought two sets of these for the front and rear of the vehicle. I also recommend installing a good Amp to allow for optimal sound, These speakers are designed for power. [ SCOTT Dec 22, 2015 ]
This component speaker system includes two 5-1/4" woofers, 2 tweeters, and 2 crossovers. So there would be 4 speakers total, 2 woofers, 2 tweeters. The two external crossovers direct the right frequencies to the tweeters and woofers to maximize their performance. [ Kenny Dec 22, 2015 ] Staff
I do not know I installed them in an 2008 Corolla. [ GEORGE Apr 06, 2015 ]
I had these speakers installed in my '03 mitsubishi lancer & they are way better then stock speakers in my opinion. A must buy in my book. [ Jackson Jun 17, 2014 ]