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Polk Audio DXi651

6-1/2" 2-way car speakers — also fit 6-3/4" openings

65 Reviews | 1 question - 3 answers

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Item #: 107DXI651

In Stock

Was: $99.99

Sale: -$25.00

Installation gear for most cars

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Our take on the Polk Audio DXi651

Go ahead, circle the parking lot till your favorite song is over. Polk Audio's DXi Series speakers will make you want to hit "repeat" so you can hear it all over again. Polk uses a high-tech approach and ideal materials to give your tunes an exciting new edge.

Polk Audio DXi651

Enjoy your music even more

Go ahead, circle the parking lot till your favorite song is over. Polk Audio's DXi Series speakers will make you want to hit "repeat" so you can hear it all over again. Polk uses a high-tech approach and ideal materials to give your tunes an exciting new edge.

Precision woofers showcase your music

The DXi651 speakers feature 6-1/2" polymer composite cones that are lightweight and stiff, so they can create a big sound with minimal distortion. Polk analyzes their drivers in motion to ensure that cone movement is even and precise. Polk also uses laser imaging to craft woofer cones that are perfectly balanced to resist distortion-causing resonances.

Aluminum dome tweeters broadcast detailed sound

Each 3/4" aluminum dome tweeter brings out the high-frequency highlights in your music, so you'll hear every detail of your most enthralling musical moments. From an intensely quiet acoustic pluck to the most exhilarating electric solo, it'll be a very entertaining ride.

Crisp clear sound. Plenty enough for bass for me. Easy install. Very sturdy construction.

Walt, Janesville WI

Featured Video:

What's in the Box:

  • Two 2-way speakers
  • 2 Grilles
  • Eight 1" Self-tapping screws
  • Eight 3/8" Self-tapping screws
  • 8 Speed clips
  • 2 Spacer/Adapter brackets
  • 2 Foam rubber gaskets
  • Owner's Manual (English/ Spanish/ French/ German/ Italian/ Portuguese)
  • Online product registration information

Product Highlights:

  • 6-1/2" 2-way car speakers (pair)
  • supplied adapter rings allow for fit into 6-3/4" locations
  • polymer composite woofer with butyl rubber surround
  • 3/4" aluminum dome tweeter
  • power range: 6-60 watts RMS (180 watts peak power)
  • frequency response: 35-22,000 Hz
  • sensitivity: 92 dB
  • top-mount depth: 2"
  • warranty: 1 year
  • Our 60-day money-back guarantee

Polk Audio DXi651 Reviews

Average Customer Review:

65 Reviews

Polk Audio DXi651

Written by: Walt from Janesville WI on May 1, 2016

2006 Chevrolet Colorado
Crutchfield Customer Review (What's this?)

Crisp clear sound. Plenty enough for bass for me. Easy install. Very sturdy construction.

Pros: Great sound. Well made.

Cons: none

Polk Audio DXi651

Written by: Doug from richmond, VA on March 5, 2016

Crutchfield Customer Review (What's this?)

The best speakers for the price. Crutchfield service is excellent.




Written by: Sean D from Plano, TX on February 27, 2016

2006 Saturn ION 3
Crutchfield Customer Review (What's this?)

If you're shopping within the same price range - I easily give these 5 stars. Probably 4 stars if you're comparing against higher end stuff. These speakers sound fantastic in my car - on par, if not better, than some components I've had. They actually have a shocking amount of bass (I have a sub, but turned it off briefly to see how these sounded), and overall just sound really smooth. My only gripe is highs can hiss a bit, but you can partly take care of that with EQ.

Pros: Very clear Rich mids Good highs

Cons: Highs can hiss a bit Significantly less sensitivity vs the speakers they replaced

Touareg Dynaudio Replacement

Written by: Jay99 from Fairbanks AK on January 12, 2016

2007 Toyota Tundra
Crutchfield Customer Review (What's this?)

Excellent replacement for my intermittent rear woofer issues in a 2009 VW Touareg. Originals were on a odd riveted plastic subframe. Once removed, the 951's matched the mounting pattern perfectly ! Wire jumpers from the factory plug receptacle to the speaker and install the assembly with a bead of silicone and new rivets. Cleared the error codes and saved $182 over the cost of the OEM originals.

Pros: Better sound for way less money !

Cons: Not the easiest install with the factory rivets but the second one took less than 20 minutes.

great speaker

Written by: mt R from Hudson, NC on December 6, 2015

Crutchfield Customer Review (What's this?)

work great, sound great. Good instructions



Great Sound!

Written by: PatrickJ from Oregon on October 16, 2015

Found these used locally, but wanted to say that that these were a vast improvement over stock, and noticeably better than the Kenwood they replaced. Although not in the 'boomy' subwoofer category, with my Nakamichi 25w rms per channel h/u, the bass is full & tight. Mid and upper ranges are clear without being too bright. These qualities would no doubt be more pronounced with more power, but VERY enjoyable as is. Mozart / Merle Haggard / Metallica - all are vastly improved with the DXI651's! Only issue on the install into the front doors of my 2001 Nissan Frontier Crewcab, was that the mounting screw head diameter was too large for the recessed area (pocket) on the speaker flange. Had to bend the two metal corners on each of the mounting holes away to allow sufficient room for the screw to seat. Also, the four screw holes drilled into the plastic Nissan speaker ring are not all drilled perpendicular to the mounting surface, and may not exactly line up with holes on the Polk (or other) units. Rotated speaker to get best fit, but still may be issue. Overall, very happy with purchase!

Pros: Tight bass response, build quality, full mids, smooth highs.

Cons: Stock mounting screw fitment to Nissan speaker ring; wish I could have bought from Crutchfield for the lower price of used pair

Great Speakers

Written by: Justin from Florida on September 25, 2015

2008 Chevrolet Tahoe
Crutchfield Customer Review (What's this?)

These worked very well with my stock stereo in my 2008 Tahoe. Used in the front doors.




Written by: Jeff w from Pennsylvania on July 11, 2015

2014 Volkswagen Jetta
Crutchfield Customer Review (What's this?)

Great sounding speaker, a nice upgrade from factory speakers. Price was very good, easy install



Nice speaker

Written by: Brad from Georgia on April 6, 2015

2001 Nissan Pathfinder
Crutchfield Customer Review (What's this?)

I like these speakers, replaced the factory ones in my Nissan Pathfinder. Replacement was easy and they sound great

Pros: Excellent little speaker for the price, good high frequency clarity

Cons: Very little bass response... these should only be used as mid/high Bass needs to come from a different driver!

Polk Audio DXi651

Written by: AKaudio from Arizona on March 23, 2015

2004 Subaru Forester
Crutchfield Customer Review (What's this?)

Bought the Polk Audio DXi651 for a 2004 subaru Forester X. Had good set of Polks in my 96 legacy. These are not so good. The spec indicates response to 35Hz on the low end. I measured the free air resonance frequency fs = 118Hz. I couldn't post the measurement data of impedance vs frequency. Put them in any kind of enclosure and expect this to raise somewhat although the compliance is pretty stiff so the door panel compliance is probably negligible. This explains the complaints of no bass. In contrast I measured fs = 83 Hz for the original subaru speakers. Also the noticed an erratic impedance of the crossover/tweeter at the higher frequencies. They have a little more on the high end then the original subaru speakers but by the time they go in the factory door panels it is not much of a benefit. The loss of bass is inexcusable in a 5.5" driver. The main problem is that the 35 Hz spec is misleading. Its a second order system with 40/db decade from fs. The spec should say -20DB@35 Hz.

Pros: Fit with brackets and wiring provided

Cons: Bass response

Good replacement for factory speakers.

Written by: MHall from Abbeville, SC on February 25, 2015

2007 GMC Sierra
Crutchfield Customer Review (What's this?)

Quality speaker for the price. Replaced factory speakers and these sound better.

Pros: Easy installation. Quality product

Cons: Bass not as strong as expected but still better that factory speakers.

Meh...not impressed

Written by: IVI Guy from Oregon on February 14, 2015

2012 Subaru Impreza
Crutchfield Customer Review (What's this?)

I bought 2-pairs on sale for my 2012 Impreza, a set for the front and a set for the rear. Last year I replaced the factory head unit with a Pioneer FH-X720BT, not high end but decent enough for the money. First I installed the rears then fired up a few songs to make a comparison to the factory speakers. I started by shifting center balance all the way to the rear, then all the way to the front, and back and forth. Honestly, I think the factory speakers sounded better even though they are clearly an inferior quality product. The mids and highs on these Polk speakers simply aren't as clear as I was expecting. Despite being less than impressed I went ahead and replaced the front speakers in the hope that I could dial things in later. I was able to make them sound a bit better though still not quite as good as the factory junk that came with the car. The stereo is kind of a budget model so maybe my expectations were a little too high. Installation was easy and straightforward and these speakers fit more flush in the front doors of my Impreza than the rear. If you happen to have the same car know that you will have to reroute the speaker cables through the inside of both front doors and I highly recommend securing them with tie straps to the wiring harness close to where it enters the door so they don't interfere with window operation. In the end I am neither impressed nor disappointed. I do plan on installing a subwoofer later this year, maybe that will help

Pros: Nice build quality, built-in crossovers.

Cons: Average sound.

Polk Audio DXi651

Written by: Anonymous from New Jersey on February 1, 2015

Crutchfield Customer Review (What's this?)

For the most part an improvement over the oem garbage from GM, with the exception of bass.

Pros: Good service. Quick ship. Speakers have nice highs and mids.

Cons: Would have wanted more bass

Big improvement over stock

Written by: Anonymous from Muncie, Indiana on January 18, 2015

2013 Subaru Outback
Crutchfield Customer Review (What's this?)

I was having some trouble with a window and took the opportunity to upgrade the front speakers in my wife's 2013 Subaru Outback. The Polks are a big improvement in overall sound. As expected, they are weak in the low frequency range. I plan to add a small under seat sub to fill in the lows a little. My only regret is not doing the rears also.

Pros: nice clear sound

Cons: weak bass

Polk Audio DXi651

Written by: buck from ogdensburg ny on January 17, 2015

2008 Chevrolet Silverado
Crutchfield Customer Review (What's this?)

I put these in my 2008 Chevy Silverado ext cab and they sound great with factory radio.



Installed in 2009 Subaru Impreza GT

Written by: J from Bristol, VA on January 9, 2015

2009 Subaru Impreza WRX
Crutchfield Customer Review (What's this?)

Very good speakers, especially for the price. Not too bright and has good bass response. Good choice

Pros: Good quality and sound. Easy to install

Cons: none

Excellent speakers; easy to install

Written by: GreggS from Georgia on January 4, 2015

2003 Subaru Forester
Crutchfield Customer Review (What's this?)

The DXi651's are excellent speakers for the price. The included mounting adapter made it possible to use the original mounting holes instead of having to re-drill. Considering I was installing the speakers in an 11 year old car that is not as water-tight as when new, the fact that the speakers are "marine certified" is a bonus. The sound quality is very good.

Pros: Flexible installation options with included mounting adaptor; marine certified; excellent value


Great sound

Written by: Anonymous from Morgan City, LA on January 2, 2015

2007 Chevrolet Silverado (New Body Style
Crutchfield Customer Review (What's this?)

These speakers sound great and have a great design. Only issue I had was no speaker wires in the box. Bought two pairs and love them.

Pros: Sound clarity

Cons: No speaker wires

Polk DXi651

Written by: Anonymous from Greenville SC on December 21, 2014

2008 Saturn Outlook
Crutchfield Customer Review (What's this?)

Im very happy with these speakers, especially for the price. Installed in Saturn Outlook.



Polk Audio DXi651

Written by: one2sho from Barrigada, Guam on December 13, 2014

I give these speakers 5 stars.. It fit right in with no problems.. The speaker wire harness made the install a breeze.. The sound is great, I used some Boom Mat speaker baffles & I got to say; Awesome..

Pros: Great Fit & Finish.. Super clear sound.. Polk Audio reputation...


Polk Audio DXi651

Written by: Anonymous from 26719 on December 7, 2014

Crutchfield Customer Review (What's this?)

2 thumbs up

Pros: Great fit into my silverado. Sound quality is awesome

Cons: None

Polk Audio DXi651

Written by: Luke from Florida on November 25, 2014

2008 Chevrolet Silverado
Crutchfield Customer Review (What's this?)

The speaker sound great for the value. I will say that that are a lot of bang for your buck.



polk speakers

Written by: zeccarias from 32960 on November 15, 2014

Crutchfield Customer Review (What's this?)

Didn't really notice a difference from the factory speakers. Just the sound was a little more twangy.

Pros: Speakers did come with brackets

Cons: The frame seems cheep and flexes. Tweeters sound twangy

great speakers

Written by: tom from Denver, CO on November 10, 2014

2014 Subaru XV Crosstrek
Crutchfield Customer Review (What's this?)

I can't find anything about these speakers that I don't like. They do exactly what they're supposed to do, and they do it well. I've seen reviews talking about weak bass response, but those reviews were clearly left before the buyer gave the speakers a few weeks to break in. Once they break in, they will give you just as good of bass response as you can expect out of a 6.5" speaker, and maybe even a little better. I got these on sale, which made it even easier to be satisfied. Remember: every ear is different, so you need to find the speaker for you. These are slightly more bright than the Kickers I had in my last car, but more warm than the Infinity speakers I had before those, which is perfect.

Pros: solid build quality, not too warm, not too bright sound.

Cons: I wish speaker companies would start selling grills separately and charging a few bucks less for the speakers... I've NEVER used grills that come with coaxial or component speakers for my car because I use my factory locations, like everybody else.

Good Speakers Overall

Written by: JP from Vermont on November 3, 2014

2008 Chevrolet Silverado
Crutchfield Customer Review (What's this?)

Put these in a Chevy Silverado to replace all of the 4 factory door speakers. I expected a bit more of an increase in punch and sound quality over the stock speakers, but overall they are a good sounding speaker and have improved the audio in my truck.

Pros: Easy to install, good sound overall

Cons: distortion at high volumes, not crystal clear sound, not a lot of bass punch

2014 Mazda 3

Written by: Hector from Villa Park, IL on October 22, 2014

2014 Mazda 3
Crutchfield Customer Review (What's this?)

Installed these in my 2014 Mazda 3 sedan, base model. Front door speakers. OEM speakers weren't worn or old, but they definitely lacked in clarity and depth. I installed these and there is an immediate difference. Clean, crisp sound with better bass response and no distortion. At this point, it makes the rear OEM speaker's sound lacking. May have to purchase another set in the future. With all this in mind, none of the adapters included work. Had to custom mount it to the OEM units, destroying the OEM speakers, which really wasn't a loss. I understood the risk with installing these in such a new car.

Pros: Great sound even with the OEM headunit powering these.

Cons: None.

Disappointed Bass just cut out on one

Written by: Bill S from Richmond VA on October 12, 2014

Bass just cut out on one. Of course this happened after warranty expired. But now I need to replace both since they come in pairs.

Pros: The other 3 sound good

Cons: Left rear only the tweeter works

Polk Audio DXi651

Written by: Anonymous from Belcourt N.D. on October 1, 2014

2011 Chevrolet Silverado 2500/3500
Crutchfield Customer Review (What's this?)

easy install and the perfect base



Great pick for 6.5 inch speakers

Written by: Cruisediesel from Park City, UT on August 25, 2014

Crutchfield Customer Review (What's this?)

Excellent choice for 6.5's. They sound great and for my purposes being marine ready was an added bonus. I installed these in my 84' BJ42 Toyota Land Cruiser. The car is off for months at a time so I wanted durability as well as great sound.

Pros: Quality sound and price

Cons: Non so far

Can't ask for better

Written by: Rudy from San Antonio, TX on August 19, 2014

2004 Chevrolet Colorado
Crutchfield Customer Review (What's this?)

Wow, These speakers have rich bass, good mids, and clear highs. Perfect for my regular cab truck. I am very happy with them. After a few days of jammin they really came to life. They play everything from the Grateful Dead(Classic Folk/Rock/Jams) to Tipper(Glitch/Dub) with no issues. Don't delude yourself into thinking these will set off car alarms and you will be happy. I wonder what they will sound like amplified with a sub behind, but thats down the road, and I couldn't be happier as they are. Ordering from Crutchfield was a new experience for me, but these speakers came with the adapter harness to hook up to the stock cables (free) and instructions on installation. I must admit I am now a DXi and Crutchfield customer for the forseeable future :)



Polk audio

Written by: Michael from Walworth WI on August 10, 2014

1998 Ford Ranger
Crutchfield Customer Review (What's this?)

Love the Polk audio, they hold up to my amp and sound great. I have blown many speakers and these seem to hold up very well. Would definitely buy more Polk audio speakers in the future. Had them installed in a Jeep grand cherokee and now in a 98 Ranger with a 12" sub. Very nice sound.

Pros: Easy to install, Sound is great. They hold up to my amps power.

Cons: None

Polk Audio DXi651

Written by: buz from SF, CA on July 24, 2014

2007 Toyota Tacoma
Crutchfield Customer Review (What's this?)

Very good speakers for the price.

Pros: Price performance, perfect for stock head unit

Cons: The tweeter extends out too much


Written by: Anonymous from Dover, NH on July 7, 2014

2003 Volkswagen Passat
Crutchfield Customer Review (What's this?)

just installed these in my car and they sound amazing, the base is very powerful and they just sound great all over

Pros: powerful base

Cons: none

Great car speaker !!!

Written by: J.Oz from West Chester, PA on June 19, 2014

2002 Nissan Sentra
Crutchfield Customer Review (What's this?)

Two words...Loud and Clear. Great instructions from Crutchfield, as always...

Pros: - High Sensitivity made the Polk's a great match for the Kenwood 22w/ch head unit - Punchy bass for a small speaker - Solid high performance at the high end

Cons: None to speak of...

Solid speakers

Written by: BA from Michigan on June 9, 2014

2013 Chevrolet Volt
Crutchfield Customer Review (What's this?)

I bought these to upgrade from factory sound in a Chevy Volt (w/o Bose). Overall I am pleased. You won't be mistaken for having a powered subwoofer, but sound is full and well balanced. Bass is only moderately, but still noticeably, better than stock. This is based on running off the factory HU. An amplifier would probably be even better. Service from Crutchfield was excellent as advertised.

Pros: Clear crisp sound Decent bass Easy install

Cons: Needs lots of power for full potential

2011 Suburban Door Speaker Replacement

Written by: Esteban from Chambersburg on June 1, 2014

2011 Chevrolet Suburban
Crutchfield Customer Review (What's this?)

Expected better but to be fair the stock deck leaves a lot to be desired. Slight difference in bass, but still lacks depth in overall sound. I wish I had the money to invest in a better deck to run my amp and subs but it shall wait. I am very picky when it comes to quality sound so hopefully these will sound better hooked to an amp.

Pros: Fit perfect with the supplied materials, easy to install and connect.

Cons: Wish they had better sound quality with the stock deck alone.

Polk speakers

Written by: Kevin N from Rochester,NY on May 17, 2014

Crutchfield Customer Review (What's this?)

Excellent speakers. Easy to install. Huge improvement over the stock speakers. I would recommend these speakers.

Pros: sound great. easy to install

Cons: none

Polk Audio DXi651

Written by: W. H. from Richmond, VA on May 11, 2014

2014 Jeep Wrangler Unlimited The sales man suggested these to me (bought in store), so I went with them. The highs are nice, compared to the stock cone speakers. But the low's on the other hand could use some work. They are ok at a low volume, but when trying to turn them up a little.... They sound like someone is thumping a 5 gallon bucket. Granted these are in the over head sound bar, the factory speakers did not do this. So, back to the drawing board for me.

Pros: Nice highs

Cons: The bass is non-existent.


Written by: Krewella from St. George, Utah on May 7, 2014

1992 Honda Civic
Crutchfield Customer Review (What's this?)

This speaker set has been amazing since installation, easy installation, clear, simple fit, the tabs break off easy for ring installs, and the best part is the sound.

Pros: Easy install, great sound, clarity, well-designed, waterproof, tight sound seal to door panel and deck panel, durable, directable tweeter sound, price.

Cons: Considering that I will get a sub and amp for that sub, this con doesn't really matter for me, but the low-end bass is lacking a little, pumped up through the new head-unit and it sounds good and clear, but it's not ground-shaking, mirror bouncing, and teeth rattling.... But it will be.....

Great Speakers

Written by: Lil'Yeshua from Pageland SC on April 27, 2014

2009 Nissan Versa
Crutchfield Customer Review (What's this?)

For my new stereo install project,I was looking for speakers that could handle low frequencies and the Polk's have a frequency range of 35-20000 hz. In my case,these Polk's eliminate my need to run 8" woofers in my front kick panels. I've bought the Polk Audio DB651's before to use in my mini SUV s sound system for mid bass fill along with a pair of 12" subwoofers. The DB651's are still functioning perfectly as I have the frequency cutoffs set right using my Blaupunkt Bremem MP76 head unit as to not send the lowest frequencies through them. I also use custom mounted A-pillar tweeters I stalled to bring the sound stage up. Whereas the DB651's have bigger magnets,the DXi651's have smaller magnets,having stiffer speaker surrounds to limit woofer excursion. I have yet to install these DXi651's but I think they'll do an admiral job.

Pros: Good sound reproduction quality and sound frequency spread

Cons: None

DIY speakers

Written by: Scott from Phoenix AZ on April 25, 2014

Crutchfield Customer Review (What's this?)

Bought these speakers based on recommendation from Crutchfield rep and customer reviews. I was skeptical I just got Sold speakers. Not the best simple upgrade 6.5 speakers with some bass. It was explained to me that I would loose some bass over stock, because they are paper. These sound great in the rear seat. Produce more bass than Rockford fosgate so components I have in front. Actually going to buy the Dix components and eBay the rock fords.

Pros: Great clarity. Fair price.

Cons: None found.

They sound great

Written by: Disco bob from Thornton co on April 20, 2014

Not much to say here, great speaker looks like materials will last. Wish I had an amp running them but they still sound great from deck power.

Pros: Wonderful, crisp and sound awesome for the size:)

Cons: Once again this is cosmetic and 80% won't even use the grills...Square grills, under tight quarters this can be tough to get them straight on rear decks, the mount hole ends up so close to the window it is very hard to get a hole drilled and a screw mounted.

Not very good

Written by: Lance7489 from Lancaster, NY on April 17, 2014

Crutchfield Customer Review (What's this?)

Very disappointed in these. The factory speakers in my 2013 Impala sounded much better. Very poor bass. I know you're not going to get much out of 6.5" speakers but these are not good. The 6.5" kickers I bought for my wife's Malibu were alot better. The cones on these are very stiff & just don't move enough air to generate satisfactory bass.

Pros: Good highs & midrange.

Cons: Again, poor bass response !!!!!!!

Great in my 06 avalanche

Written by: Brian k from Okc on April 6, 2014

Great clear crisp sound

Pros: Fit factory insert Great bass and clarity plus used a 180 watt alpine pre amp

Cons: None

not what i was expecting

Written by: matt from nc on March 23, 2014

Crutchfield Customer Review (What's this?)

I own a silverado and I wasn't expecting a lot I just wanted a little bit better then stock and little more bass and I know I wouldn't get a lot of bass cause its just a door speaker with no amp but I wouldn't really say it was much better then stock and the bass is pretty muddy and never clean in some bass heavy songs I pretty much need to turn the bass to a -6 because it sounds so bad and I keep the bass at 0

Pros: fixed my busted speakers not really a pro but kind of

Cons: not any better then stock

Polk Audio DXi651

Written by: Blue nissan from Maryland on February 23, 2014

2004 Nissan Maxima
Crutchfield Customer Review (What's this?)

Great sounding speaker

Pros: Nice high and lows

Cons: Should have added speaker wire

Great Fit & Great Sound

Written by: Joe from Hudson, NH on January 11, 2014

Crutchfield Customer Review (What's this?)

I purchased these Polk DXi651 to replace the speakers in the rear deck of my 2002 Honda Civic EX sedan. They fit perfectly in the rear shelf without any adapter brackets. I did have to drill 3 new holes but that wasn't difficult. This model of the Polk speakers was not recommended by the customer service reps at Crutchfield. The recommended speaker size by Crutchfield was 5 1/4" but I wanted to give these 6 1/2" a try anyway as I wanted a speaker that would provide a little more bass. These speakers have a great balanced sound and they do provide a decent bass response for my over 50 ears. I wasn't looking for the deep bass of a sub woofer just a well balanced sound and these speakers did not disappoint. This was my first purchase from Crutchfield and I am very satisfied -- they provided all the necessary accessories for the install at no extra charge and the installation instructions were very helpful.

Pros: Great balanced sound. Perfect fit in the rear shelf of a 2002 Civic

Cons: None

Quite the Upgrade

Written by: MusicMan from Orefield,PA on January 11, 2014

1999 Volkswagen Passat
Crutchfield Customer Review (What's this?)

What an upgrade for my daughter's '99 Passat! And at a great price. I popped out the 4 stock door speakers and mounted these with ease. Matched up with a Sony MEX-BT4100P and Sound Ordnance 50W RMS amp these Polks are delivering clean crisp sound and with plenty of bass given their small size and disadvantaged mounting location. Although the bass is fine for this 50 year old, the kids love the boom so we threw in a Sound Ordnance 80W RMS powered sub in the trunk. Finally, kudos to the Crutchfield experience, all the right installation instructions and tools are always thoughtfully included.



polk coaxial

Written by: Anonymous from aiea, hi. on January 9, 2014

2006 Subaru Forester
Crutchfield Customer Review (What's this?)

These are very good speakers. Crisp highs with clean bass. It was a big improvement over factory oem speakers. They are well made and durable. I'm very pleased with thier performance.

Pros: Reasonably priced, well made and aesthetically pleasing.

Cons: None

Polk Audio DXi651 Speakers

Written by: danF from Charlotte, NC on December 20, 2013

Crutchfield Customer Review (What's this?)

Great sound once i learned the Alpine receiver adjustments. Origninally installed with factory 18w and now with Alpine power pack at 45w.

Pros: Good sound. Reasonable price.

Cons: Had to play with template for door mounting, too long. Bigger diameter / longer holes required for my 2002 Nissan Frontier.

Polk Audio Speakers

Written by: Mike from Mountain Home AR on November 15, 2013

2008 Chevrolet Silverado
Crutchfield Customer Review (What's this?)

Installed them on a 2008 Chevy 2500 HD crew cab on the back doors. High quality speakers and the brackets and wire harness made installation a breeze. The bracket clips did have be modified slightly by grinding off the edges just a little.

Pros: Great product and service from Crunchfield. Also good price...

Cons: None

Quality sound

Written by: Scott from Ocean city, nj on October 30, 2013

2003 Chevrolet Silverado 1500
Crutchfield Customer Review (What's this?)

Quality sound, makes the head unit sound so much better, They replaced cheaper aftermarket speakers

Pros: Great sound Great price for the quality of the speakers Crutch field delivers

Cons: None

Great sound, easy install

Written by: Jeff from Frisco, TX on October 28, 2013

2008 GMC Sierra
Crutchfield Customer Review (What's this?)

installed all 4 speakers in the doors of my 08 Sierra. for some reason, all door speakers went out but from what I have heard, sounds common in the Sierra/Silverado. You can install these yourself, don't take to a shop. Honestly, the hardest part is getting the door panel off. the speakers sound great...I think anything would sound better than stock though! Nice base (better than stock). Supplied mounting brackets and speaker harness worked like a charm. I think total install took a couple of hours.

Pros: great sound, easy install

Cons: none for now

Improvement over OEM

Written by: CC from Birmingham, AL on October 15, 2013

2008 GMC Sierra
Crutchfield Customer Review (What's this?)

I used these Polks to replace my original speakers in my 2008 GMC Sierra crew cab. Definite improvement over stock speakers. For a 6.5 speaker these have really good bass. They do not deliver the mid range sounds as good as I would like, even after adjusting the EQ (stock radio). I may be picky but that is my only reason for 4 stars. I saw these speakers at Best Buy for comparison, got a better deal from Crutchfield. Getting free install equipment saved me about $55 for four speakers, way to go Crutchfield!!

Pros: Full sound, good bass, FREE install equip(speaker bracket and wiring harness needed for my vehicle), plenty of mounting options, easy to install

Cons: Mid range sounds lack a little for my taste

Awesome buy!

Written by: ScottS from Clarksville, NY on September 18, 2013

2008 GMC Sierra
Crutchfield Customer Review (What's this?)

Outstanding sound and very easy install. Will be buying these for the rear doors of my '08 Sierra very soon.



Excellent sounding, plenty of mounting holes

Written by: M_D_B from Parma, OH on August 21, 2013

2010 Subaru Forester
Crutchfield Customer Review (What's this?)

Very simple: these speakers sound great, have better low-end than I expected, and provide lots of mounting holes for various applications. Love 'em.

Pros: Easy to mount, very good low end, tweeters can be tilted towards listener (slightly.)

Cons: None.

Polk Audio DXi651

Written by: PlanetKiller from Aloha, OR on August 20, 2013

2006 Dodge Ram 2500
Crutchfield Customer Review (What's this?)

I installed these in the rear doors of my 2006 Ram2500. Fit nicely but I did need to drill new holes to mount them. Very nice sound. Really surprising when compared side by side with the stock ones, both looks and sound. They hide behind the factory door panels and everything looks stock and clean. I am running the Alpine KTP-445 amp and it really woke them up!

Pros: Good sound, east install w/ a few new holes.

Cons: None really

A crisp speaker

Written by: Mychal from Tampa, Fl on August 18, 2013

2006 Chevrolet Silverado 1500
Crutchfield Customer Review (What's this?)

After hearing many of the 6 1/2 speakers on this site (sony, rockford, infinity, kenwood etc) I can vouch for this polk speaker in saying it sounds pretty good hooked up to just an aftermarket radio. If you really want to hear it come to life then amp it. Overall a good sound for 75 dollars.

Pros: Good mids and decent lows and highs

Cons: Could be a little better highs and lows

Factory Speaker Upgrade

Written by: Steve from Mount Pleasant, WI on August 18, 2013

2008 Chevrolet Silverado
Crutchfield Customer Review (What's this?)

These speakers replaced my stock Bose front door speakers in my 2008 Chevy 2500HD. The quality is superior to the Bose speakers and the sound is more crisp.

Pros: The sound quality is great, especially for the affordable price.

Cons: none

Solid Speakers

Written by: Matt from Tucson, AZ on August 16, 2013

1990 Nissan Hardbody
Crutchfield Customer Review (What's this?)

I love these speakers, they really have that low range I was looking for. However I feel like it does kind of muddle the sound and I am currently running them without any extra amplification so in bass heavy songs they do kind of struggle a bit to still keep the entire sound together. But in all I would totally buy these again and recommend them highly, but I do feel these speakers were meant to be amplified.

Pros: Bass response, sound clarity.

Cons: The bass can overwhelm the speaker making the sound quality suffer noticeably. (could be more of a wattage problem on my end though so I am not entirely blaming the speaker!)

Great replacement speakers

Written by: Schwipr from Milan, IN on August 14, 2013

2007 Chevrolet Silverado (New Body Style
Crutchfield Customer Review (What's this?)

Bought these to replace some blown factory speakers. Installation was easy and the sound quality was much improved. Great range on these. Very good speakers for the price.

Pros: Great sound & value


Good for the price.

Written by: Jimmy from Temple, Tx on July 26, 2013

2013 Chevrolet Silverado 1500
Crutchfield Customer Review (What's this?)

These speakers provide good lows and highs. The midrange isn't particularly stron. But with the Helix PP50 added to the equation, the factory system rocks.

Pros: Booming bass. Crisp highs.

Cons: A little weak in the midranges. But overall, a good speaker.


Written by: revheat from Soulsbyville, CA on July 10, 2013

2005 Chevrolet Silverado 1500
Crutchfield Customer Review (What's this?)


Pros: Cant go wrong with polk

Cons: None

Maxi Mini

Written by: Dick from WA State on July 7, 2013

Crutchfield Customer Review (What's this?)

Great range, nice base response and as these are installed in rear deck the tilting tweets work very well indeed.

Pros: great value

Cons: None

Amazing sound

Written by: AntD from Tucson AZ on July 6, 2013

2009 Toyota Matrix
Crutchfield Customer Review (What's this?)

My new Polk speakers have made a huge difference. They have excellent clarity and just enough thump! Couldn't be happier with my DXi651 speakers.

Pros: Good hi's Good mids Good lows

Cons: None


Hands-on research

What's in the box?

Download the Polk Audio DXi651 manual

  • Two 2-way speakers
  • 2 Grilles
  • Eight 1" Self-tapping screws
  • Eight 3/8" Self-tapping screws
  • 8 Speed clips
  • 2 Spacer/Adapter brackets
  • 2 Foam rubber gaskets
  • Owner's Manual (English/ Spanish/ French/ German/ Italian/ Portuguese)
  • Online product registration information

Product Research


High Efficiency Design: The Polk Audio DXi Series speakers feature a high efficiency design; meaning better sound and more volume using less power.

Dynamic Balance Driver Technology: 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: For a driver to reproduce complex sounds accurately, the cone must move exactly the same distance and manner in both directions. The Klippel distortion analyzer, a device that uses a laser and sophisticated software to do large-scale analysis of drivers in motion, lets Polk optimize the speaker's motor structure, voice coil alignment, and suspension to yield the best possible performance.

Composite Cones: Each speaker features a Dynamic Balance, Bi-Laminate composite, polypropylene cone woofer. These composite cones feature tremendous stiffness-to mass ratio, resulting in faster transients and finer detail.

Rubber Surrounds: For a smoother response and improved durability, the speaker uses rubber surrounds.

Aluminum Dome Tweeters: Each speaker features a 3/4" aluminum dome tweeter for clear, accurate highs. Once the speakers are mounted, the tweeters can be tilted (approximately 25°) for optimum imaging.

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

Product reviews from the Crutchfield Labs

Four popular car speaker lines
by Robert Ferency-Viars

We listen to Alpine Type-S, Polk Audio DXi, Infinity Reference X, and Rockford Fosgate Punch car speakers in the Crutchfield Labs.

What are the Labs?
Q & A

Customer Q&A

1 question already asked

Yes [ Robert  Dec 01, 2015 ]
yes they come as a pair [ JOE  Dec 01, 2015 ]
THe price is for 2 speakers, and they sound great [ Douglas  Dec 01, 2015 ]