Watch a first-look video

Kicker 40CSS684

6"x8" component speaker system

Item #: 2064CSS684

In Stock

52 Reviews



Installation gear for most cars

Your price: $129.99 Earn up to 130 Rewards points

Add to Cart

+ Add to wishlist + Email me alerts for this product

View all associated offers

Does it fit my car?

Select your car

Find what fits your car

Kicker 40CSS684

It's time for an upgrade

Upgrading the old factory speakers in your car will give you a huge bump in sound quality, and Kicker designed CS Series speakers to get your sound system rockin' without breaking the bank. You'll enjoy your music even more when you hear all the details that your muddy-sounding factory speakers couldn't begin to reproduce.  

Bring on the treble and the bass

Kicker's 40CSS684 component speaker set provides low-end from a tough 6"x8" polypropylene woofer, with a polyester foam surround that will stay strong for years to come. The separate 3/4" titanium dome tweeter takes care of the vocal and instrumental details that'll really bring your music to life. The outboard crossover network allows you to pick from three different tweeter level settings so you'll get balanced sound wherever you're sitting.

Installation note: You'll need a pair of our universal backstraps to install the tweeters in the factory locations.

Product Highlights:

  • component speaker system includes 2 woofers, 2 tweeters, and 2 crossovers
  • 6"x8" polypropylene woofers with polyester foam surrounds
  • 3/4" titanium dome tweeters
  • external crossover network with 3 tweeter levels (0, +3, +6 dB)
  • power range: 2-75 watts RMS (225 watts peak power)
  • frequency response: 40-21,000 Hz
  • sensitivity: 90 dB
  • top-mount depth: 2-5/16"
  • warranty: 1 year
  • Our 60-day money-back guarantee

Why install component speakers?

A component speaker system gives you the best possible performance from your car audio system. A system consists of separate woofers, tweeters, and crossovers, each designed to cover one specific range of frequencies. As separate components, the woofer can move freely to deliver more powerful performance, while the tweeter can be custom-mounted in a better spot up closer to your ears, revealing a whole new world of detail. Separate crossovers are far superior to the simple filters wired into full-range speakers, so the components work together for smoother, more focused sound.

Kicker 40CSS684 Reviews

Average Customer Review:

52 reviews
Review this product
Great Gear Giveaway

Submit a review and then enter to win a $350 rewards card


Review this product:

Thanks for taking the time to share your experiences about this product. Please be sure to focus your comments on the product itself. Read our Review Guidelines for more information.

Your email won't be visible. Please use the email address that is associated with your order.
(e.g., JohnD) Your review will be signed using the display name and location
(e.g., Charlottesville, VA)

Click on a star to rate the overall product on a scale of 1-5
1500 characters left
  Attach a YouTube Review
Crutchfield Video Review Guidelines
  • Only submit videos that you made or are authorized to use.
  • Do not submit videos that contain music, video or visuals that are copyrighted and belong to someone else.
  • Please see our Review Guidelines for more information.
500 characters left
500 characters left

Top Notch

Written By Blacker, Montana on Tuesday, September 29, 2015

Crutchfield Customer Review (What's this?)

Great overall response with these speakers. The woofers provide good punch for simple door speakers and while the tweeters aren't the most dynamic I've ever heard, they do compliment the woofers well. With my Clarion 7.1 EQ and 4 channel Kicker amp, these fit in perfectly. My biggest complaint is the bands of audio are not separated between the woofer and tweeter enough to meet my desires. That only really shows up when listening to music like dubstep style stuff that will have loose bass with vocals over top. The vocals become badly distorted by the sheer amount of bass coming out of the woofer. The reason why I'm not taking out a star for that is a) If you want a huge amount of punch, get a sub, we all know that, and 2) I have the low end frequencies turned way up on my EQ because I listen mostly to hard rock/heavy metal, so I have the system tuned to that style of music, not dubstep or the kind of music that would product that problem. It wouldn't be an issue at all if the frequencies were better separated amongst the woofer and tweeter, but this is a small thing in the scheme of things. These speakers put out great bass and mids for hard rock and heavy metal.

Pros: Top notch bass and mids for a door speaker, can handle a heavy load, very well worth the price.

Cons: Highs could be much more crisp, frequencies could be separated by the crossover better to maximize the sound, not the cleanest sound I've ever heard.


Written By wQQdsman, Iowa on Monday, September 28, 2015

Crutchfield Customer Review (What's this?)

Not impressed...I got these based on a recommendation by Crutchfield. At that time, I had my product advisor recommend a complete system, 6 speakers and a head unit. He went with a Kenwood head unit "that I am very pleased with" and six kicker speakers. I mentioned at the get go sound quality was a must. He recommended three pairs of kicker speakers. This component set for the front, a different set for the rear doors and a third different set for the 3rd row. I said and I kicker must have come a long way to be mentioned in the realm of quality sound...I should have listened to my gut my advisor said they are very highly rated and his defense the 2nd row and third row seem to be just fine. But this component sounds like a tin can in the tweeters and the speaker distorts with anything near 3/4 volume from the Kenwood that only pushes 22 per channel?. I have the kenwood set to 5" as it should be..its even worse on any other speaker setting via the headunit. I have pulled the level on the crossover all the way down....middle...and up to top. At top it is miserable,,,at mid level the speaker disappears and all you hear is the over tinny sound of the tweeter and at low the speaker all but disappears and your left with all tin can....If your looking for pure sound quality then I would not recommend this setup. I will most likely give these away to one of the kids at work and purchase something of higher quality.

Pros: I honestly don't have a pro to mention other than price.

Cons: Back to get what you pay for....entry level components. Over tinny for my liking and the sound is not in my realm of quality.

Great for '01 Miata

Written By Dave G, Illinois on Saturday, September 26, 2015

Crutchfield Customer Review (What's this?)

Purchased these Kicker speakers with JVC KW-R10BT head unit to replace factory (non-Bose) system in 2001 Miata (Base non-LS). Installation was easy -- Door panels have opening for tweeter that fit perfectly using a universal bracket along with a couple small screws. Main driver also fit very well with only very minor trimming of OEM protective back cover. Crossover was mounted inside door cavity by drilling a single hole above main speaker and using a small nut & bolt plus heavy duty Velcro. (NOTE: Be careful not to position crossover in path of sliding hinge rail!)

Sound quality of this system is outstanding, with plenty of low end and crisp highs - perfect for music I listen to (Classic rock, jazz, acoustic, country, pop). Speakers seem quite efficient -- Volume output is VERY loud using only the stock 22 watt amplifier of the JVC HU! Had purchased outboard amplifier to install, but found it unnecessary.

Pros: Easy installation, excellent sound quality, appear designed to last.

Cons: None to report.

Sound great

Written By BDR, Texas on Wednesday, September 23, 2015

Crutchfield Customer Review (What's this?)

Installed in 2005 F-150 which came with the "Audiophile" sound system, amazing the difference these speakers make in comparison to what the factory considers an upgraded system. Easy install, the tweeters have a threaded ring/nut to hold them on, so as long as the hole is the right size they attach nicely; no backstrap or other installation device needed. No complaints so far.

Huge improvement over stock.

Written By daniel, Oregon on Wednesday, July 15, 2015

Crutchfield Customer Review (What's this?)

Much more crisp sound than stock. Love that these are matched components and the equalizers are adjustable to fine tune the sound. I set them on +3db (middle selector), which worked great. I had to do a little custom work to mount the tweeters in the factory locations, on my 2012 Ford Super Duty but it worked great, as did mounting the equalizers, and everything looks stock. These sound great, even with a stock deck. I would highly recommend this balanced set.

Pros: Great sound and relatively easy to install the packaged kit. Much more clarity and crispness than stock components. Good bang for the buck.

Cons: Shipping box was missing one of the harness adapters for the speakers: no big deal, I just used my own connectors and called it good.

Great crisp sound

Written By Alex, Michigan on Monday, July 13, 2015

Crutchfield Customer Review (What's this?)

Installed these in the door panels to upgrade some old 2 way speakers I had moved over from an old car. The improvements are amazing they can take all the power I want to throw at them and are able to produce full base while projecting a great clear sound. I use my car as a stereo whenever I am working in the garage and I have never had a system that was so well balanced from even 100 ft. from the car.

Pros: Amazing high and mid sounds projection, Switch in the crossover to save from rewiring in order to change tweeter volume, easy install

Cons: Just make sure to balance your EQ after install.

Not bad

Written By Anonymous, Pennsylvania on Monday, June 01, 2015

Crutchfield Customer Review (What's this?)

Definitely an upgrade from factory in my 2009 F150 SuperCrew. Just having tweeters near my ears and not the floor helps. Tweeters are very "bright", almost tinny. But maybe I just need to get used to them.

Pros: Easy drop-in install. Clean look.

Cons: Tweeters sound very "bright". No tweeter attenuation. Switch on crossover is apparently for volume, and is 0, +3 or +6 db.

Great Speakers

Written By r12a13b, Hubert, NC on Wednesday, May 20, 2015

Crutchfield Customer Review (What's this?)

The speakers sound great.

Cons: The provided instructions for my application were less than satisfactory. In fact, the instructions were not even for component speakers. In addition, the removal of the door panel could have been much easier with a couple of more or better pictures.


Written By Alan, North Carolina on Tuesday, May 12, 2015

Crutchfield Customer Review (What's this?)

Excellent speakers and a wonderful upgrade from factory. '06 F250 the tweeters won't flush mount in the A pillar with the way Ford built the dash, so I surface mounted them towards the top over the dash. Sound great!! The 6x8s fit right into the same location.

Great sound

Written By Mandy, Michigan on Monday, May 04, 2015

Crutchfield Customer Review (What's this?)

Great sound!


Written By Cfloo, Blue Rapids Kansas on Sunday, April 26, 2015

Crutchfield Customer Review (What's this?)

Phenomenal sound and even better performance. Kicker has always been my go to brand but being on a tight budget this time had me worried. Needless to say, my worries are over.

Pros: Budget friendly and quality performance sound. Super easy installation and a terrific fit.

Cons: None to date

Kicker 40CSS684

Written By Anonymous, Broken Arrow, Ok on Thursday, April 16, 2015

Crutchfield Customer Review (What's this?)

I'm very happy with these speakers. They sound great, easy install, and great price. Plan on hooking these up to an amp for an even better sound.

Pros: Easy install, great sound, at a great price!

Cons: None


Written By Toolman, Salt Lake, Utah. on Sunday, April 05, 2015

Crutchfield Customer Review (What's this?)

1st off I've owned Kicker products before and was very satisfied. This time the hardest part of the install was figuring how to get door part panel off. Took about 10 minutes and everything was self explainitory. Kicker and Crutchfield, you rock! Thanks.

Pros: Easy and 100% better over factory.

Cons: None

Great speakers

Written By Patrick, California on Sunday, March 22, 2015

Crutchfield Customer Review (What's this?)

These are really great speakers. Fit perfectly in my F350. Installed a set in the front and a set in the back. cut a hole for the tweeters in the back about 4" above the regular speakers. The front tweeters I used the adapter and installed them on the tp front of the door panel. The sound is very clear and crisp. You will probably find that you will set your crossovers to 0 depending on where you install your tweeters because there is plenty of highs. Great sound. I can hear instruments in the songs that I did not hear with the stock speakers. If I were to by them again I would probably get baffles just to protect them from the elements. At least the ones that mount in the doors. I will be buying these again for my jeep.

Pros: Great fit. Great sound. Crossovers work great.

Cons: None

Perfect for what I needed

Written By Kevin L, Virginia on Friday, March 13, 2015

The speakers are very good but I really appreciate the advice from the Crutchfield consultant. I also had Crutchfield install the speakers. Very professional advice and they walked me through how and where the speakers would be installed in my 2010 F150. The original speakers sounded very muffled. I love my truck and I love music so these Kickers brought both of my worlds together.

Pros: Very radiant sound with crisp highs. Much better than what I had for sure. Good price with the install.

Cons: None so far.


Written By Anonymous, Washington on Friday, March 13, 2015

Crutchfield Customer Review (What's this?)

nice speakers

great purchase!

Written By Lloyd, waldorf md on Monday, March 09, 2015

Crutchfield Customer Review (What's this?)

Sounds great and very easy to install

Pros: Fit perfectly in my car with no modifications at all.

Cons: None

kicker speakers

Written By Anonymous, st. charles , Ill. on Monday, December 22, 2014

Crutchfield Customer Review (What's this?)

Innstalled 40CSS684. In my 011 F350 and happy with the outcome. Cost and performance what I expected. Sounds much better than the stock speakers. Also running thru my HTC. Harmon kardin iPhone. And stock am/fm CD player.

Upgrade from stock for sure

Written By irepride32, California on Friday, November 07, 2014

Crutchfield Customer Review (What's this?)

Definite clarity upgrade from stocks, I was expecting a little more bump out of them but I thing not having an aftermarket amp is why im slightly disappointed. Either way the dirty clipping sound that was coming out of the stocks on my 2010 F-150 XLT is gone.

Pros: Very clean sound, blows the stock speakers outta the water.

Cons: Was hoping for heavier mids but may be due to the crappy stock AMP. I plan on putting an after market AMP in and that may change my mind.


Written By DAN K, SPOKANE, WA. on Monday, October 27, 2014

Crutchfield Customer Review (What's this?)

overall great sound, perfect for running off deck power

Pros: exact fit for vehicle

Cons: need to reinstall once you figure out setting on crossover

Good choice

Written By Popal9800, Staten island on Sunday, October 05, 2014

Crutchfield Customer Review (What's this?)

Easy install. Nice sound. Recomend for price level upgrade.

Great sound for $$$

Written By jj, Alabama on Wednesday, September 17, 2014

Crutchfield Customer Review (What's this?)

I always wanted a set of separated speakers like this... but never thought I could afford it, but not now! Lol... I love kickers and was thrilled to get this set... and the did not dissapoint... they fit perfect into my 2007 F150 IN MINUTES... and has lots of extra decorations of you want to install them on out side of speaker hole in door and show them off... they look great, sound great and easy to buy...

Pros: Price for sound is amazing...ease of install... extra parts supporting variation of install

Cons: I did wonder what the switch on cross over should be set at... probably known buy pro, but I ma a weekend warrior so, some reading material to help a little would have been nice... but not needed..

Kicker 40CSS684

Written By MikefromMass, MA on Tuesday, September 02, 2014

Crutchfield Customer Review (What's this?)

Powered off Kenwood Excelon head unit. High pass crossed-over at 80hz as part of a 4 speaker+sub/amp system. Sounds great. Had full range sound to it before sub install and they didnt hold up all that well and clipped quite badly. Definitely recommend a HU with built-in crossover capability. May try a small amp for these (front seats) to fix imaging problem (rear-biased soundstage) due to older Mustang speaker position. Plenty of volume otherwise.

Pros: Price, Ford fit, crossover module size is manageable when hiding it during install, plenty of wiring

Cons: Poor low end (clips pretty early)

Kicker 40CSS684

Written By BrentN, McPherson,Ks on Monday, August 25, 2014

Crutchfield Customer Review (What's this?)

Sounds good, better than the old factory stuff, had to improvise a little on the tweeters, but woofers went right in.

Pros: better sound

Cons: none

Kicker 6x8

Written By Jared, Hollister, CA on Monday, August 18, 2014

Crutchfield Customer Review (What's this?)

Sounds great, and easy install in my 2006 Ford F-150. the tweeters were a bit large but i managed to us a dremel to make them fit nice and snug in the door, also looks great. Crossover was a bit hard to find a location for, but thats my vehicle problem, the crossover is fairly small in size.

Pros: easy install, great sound, great price

Kicker Speakers

Written By Jonathan, Frostburg, MD 21532 on Sunday, August 10, 2014

Crutchfield Customer Review (What's this?)

I absolutely love my Kicker speakers for my Miata MX-5. They fit perfectly, sound amazing and were easy to install.

KIicker 6x8 Yellow Series

Written By Gavin T., monroeville, NJ on Monday, August 04, 2014

Crutchfield Customer Review (What's this?)

Great base with clear crisp sound from the tweeters.

Pros: Great sound for a reasonable price

Cons: None

Great speakers

Written By Marisa, Summerville,SC on Wednesday, July 30, 2014

Crutchfield Customer Review (What's this?)

Great component speaker set, the sound is amazing and clear. It was a little too advanced for me to put in myself, so I let the professionals do it. Honestly, worth every penny for these speakers.

Pros: Loud, clear, quality


Written By Mike, Lacey, Washington on Thursday, June 26, 2014

Crutchfield Customer Review (What's this?)

Speakers are great for the price.


Written By MikeV, Babylon NY on Thursday, June 26, 2014

Crutchfield Customer Review (What's this?)

Added these kickers in my Ford Ranger sounds amazing.

Pros: Adding tweeter higher up to ear leavel bings music to life

Cons: None

Kickers F&R

Written By FullThrottleCottle, Sanford Fl on Thursday, June 26, 2014

Crutchfield Customer Review (What's this?)

Replace the front and rear factory speakers and my 1990 9F word 350 super cab. Added the kickers with a separate tweet with the splitter in the front factory size front and rear sounds great cannot wait to get in dash GPS, amp and bass. Everything was shipped as promised installation was a breeze as promised.

Pros: Crutchfield suggested this speaker set, said it would sound great and it does. One of the few things that I've stayed in budget on repairing my truck.

Cons: none

Great Product

Written By Robin, Georgia on Tuesday, June 10, 2014

Crutchfield Customer Review (What's this?)

Great product, easy to install. Much needed improvement over factory speakers.

Pros: everything

Cons: nothing

Kicker 40CSS684

Written By Anonymous, Chesapeake, VA on Wednesday, June 04, 2014

Crutchfield Customer Review (What's this?)

Installed Kicker speaker system in my 2007 Mazda Miata. Overall, installing the speakers in the doors is not overly difficult, in spite of less than optimal directions. Crossover installed nicely. Tweeter installation proved the most difficult as the stock tweeters are built into the stock tweeter mount. I called tech support, but they didn't have a viable install alternative. I ended up using the existing mount and traced out the Kicker tweeter. Using a circular core bit, I cut out the hole for the Kicker tweeter which allowed for the tweeter to be mounted perfectly. Recommend installing speaker baffles. Speaker system sound is very good with the top down.

Pros: Solid sound system. As always, tech support is great.

Cons: Installation instructions for the tweeter could be improved.

NC MX-5 Miata

Written By Scott, Alexandria, VA on Friday, May 30, 2014

Crutchfield Customer Review (What's this?)

Installed these in the doors of a 2012 MX-5. The woofers fit well. I mounted the tweeters to the door where the factory tweeter grill is located (the factory tweeter is mounted to the plastic door trim) using heavy duty dual sided tape paired with a sheet metal screw in the Kicker mounting bracket. Lined the doors with light weight Dynamat (not sure how much that did). They sound good. They've burned in well, and the factory head unit powers them fine. I get much better response when I'm running my iPhone through the aux at full volume output. I imagine with an aftermarket amp they would only sound better.

They have made it possible for me to crank music at full range with the top down and have it not sound like a phonograph in a tunnel like the factory speakers did.

I'm knocking a star because I had to get a second set sent to me; one of the woofers was distorted at low volume levels. The second set resolved the issue, and the install finished up fine over two weekends between sets. The folks at Crutchfield came through with their over-the-phone install support. As always, thanks guys.

Pros: Better than factory speakers Relatively easy install Crossover adjustable frequency response

Cons: Flawed initial woofer

Kicker 40CSS684

Written By Charlie, Texas on Tuesday, March 18, 2014

Crutchfield Customer Review (What's this?)

Bought these to put in my son's 2006 Ford F150 FX4. The mids fit perfectly. All I had to do to fit the tweeters was to trim the bottom of the factory tweeter hole by 1/6th on an inch. I placed the crossovers inside the armrests. Perfect hiding place for them and easy access if you ever need to get to them. Work great with a 10' sub under the back seat.

Pros: -Great Value for the Money

Cons: -None


Written By nigknog, great bend ks on Saturday, March 15, 2014

Crutchfield Customer Review (What's this?)

great sound

awesome speakers

Written By brian, toledo oh on Saturday, February 22, 2014

Crutchfield Customer Review (What's this?)

Bought to replace stock speakers in a '12 F150 and they sound amazing. Even running off the stock head unit they sound so much better than stock.

Pros: easy to install. May options for tweeter mounting

Cons: none

Kicker 40CSS684

Written By Anonymous, Chester, MD on Wednesday, February 19, 2014

Crutchfield Customer Review (What's this?)

Very good quality

Pros: Goes well with subs

Kicker 40CSS684

Written By Anonymous, Hillsborough, NC on Monday, February 10, 2014

Crutchfield Customer Review (What's this?)

Easy install Fantastic sound

Kicker 40CSS684

Written By Anonymous, Savannah, GA on Saturday, January 04, 2014

Crutchfield Customer Review (What's this?)

Just what my Ford F 150 needed. The sound is great and it was a easy installation!

easy installation and great sound

Written By allen, Rockmart Ga on Thursday, January 02, 2014

Crutchfield Customer Review (What's this?)

these speakers sound way better in my f250 than i expected. I would recommend these speakers

Good Overall

Written By ac, Bakersfield, Ca on Thursday, December 05, 2013

Crutchfield Customer Review (What's this?)

Installed these speakers in my F-250. Sound much better than the original speakers. Had to drill a hole for the tweeters but the extra sound was worth the extra work. Sound good at low to moderate volumes, at high volumes the bass is distorted, will have to put in a sub in the near future so I can decrease the bass to the speakers.

Pros: Easy install, great highs

Cons: Finding a good spot for the eternal box where it will not rattle can be a bit of a challenge

so far so good

Written By Anonymous, Goose Creek, SC on Sunday, November 10, 2013

Crutchfield Customer Review (What's this?)

I have the Kicker 40CSS684 and the Kicker 40CSS654 in my car. I cant hear the difference between them so this review stands for both.

Pros: Easy to install. The wires from the crossover to the speakers have different connections so there is no way to mix them up. They put out a surprising amount of bass for their size. I still will put in subs anyway because im sure heavy bass through these will decrease their life. I listen to metal, rock, country, rap and electronic or dubstep and these speakers perform flawlessly in my opinion.

Cons: The tweeters are a little loud even on the +0 setting on the crossover. There is no need for the other settings. Buy other crimp connections to connect to the input wire, the ones they give are useless. Needed to adjust the higher frequencies down in my equalizer because they were too high. That may just be my specific application though.

Awesome Product!

Written By Pete K, Tampa Bay, FL on Wednesday, November 06, 2013

Crutchfield Customer Review (What's this?)

I replaced my JVC speakers in my 95 GT Mustang with this product. For unbelievable sound, take the time to run new speaker wire to your amplifier or head unit instead of using the factory wiring harness. These speakers are very crisp with the proper accessories!

Pros: Ease of installation; crisp sound

Cons: None noted!

2013 Mustang GT 4 Speaker setup

Written By OLD DUDE, Odessa TEXAS on Monday, August 26, 2013

Crutchfield Customer Review (What's this?)

It's been awhile since I've installed any audio upgrades to a car. So many choices now. This kit took the guess work out of the whole thing. These are a great way to upgrade with out breaking the bank. I haven't been a bass head in a while. Now I'm just looking for great clear sound. Kicker delivered on this kit. Everything you need you get. Great sound, clear, nice mids, and still good bass. Took a little longer than it use to but it's a new car and I didn't want to scratch it up. Around three hours. Just what I was looking for thanks Crutchfield.

Pros: Every thing you need in one box. They sent wire harnesses to fit my mustang didn't see that coming. Was a huge help. Great sound huge upgrade from factory 4 speaker set up.

Cons: Only one con. Had to trim a little plastic off the mount in the door. Not a huge problem but worth bringing up.

Excellent Speakers

Written By Boo4ya99, Zephyrhills, FL on Thursday, August 08, 2013

Crutchfield Customer Review (What's this?)

I bought these Kickers for the front doors of my 07 F150 FX2. I was able to utilize the factory tweeter holes and the crossover fit perfectly underneath the window switch panel. These speakers perform just as I'd hoped they would!! Money well spent!!

Pros: Loud, crisp highs and clear mid bass

Cons: It can be tough to find a spot to mount the crossover if you happen to have small door space to work with.

Excellent step up from factory

Written By rinos88, Marquette Heights, Illinois on Tuesday, July 23, 2013

Crutchfield Customer Review (What's this?)

I put these in my 2002 Mustang GT to replace the stock speakers. The clarity is amazing. I can hear a level of detail that I have not heard before in a lot of the music that I've listened to for years. I'm also able to turn my head unit up quite a few notches higher than I could with my stock speakers. I have the high pass filter set at 50hz and they handle everything down to that frequency quite well. I'm running them off of my head unit and they sound amazing.

Pros: Great price, perfect fit, awesome clarity and punch. They sound amazing, even without an amp pushing them.

Cons: The instructions on how to change the different tweeter attachments are extremely vague, considering that the ones that come on them seem to have been put on super tight, as if done by a gorilla on steroids. I nearly had to use pliers to change to the flush mount setup.

Decent factory replacements - however, consider the 6 1/2" if you can

Written By TravisG, Meridian, MS on Tuesday, July 16, 2013

Crutchfield Customer Review (What's this?)

I bought these as a factory replacement for an 04 f150. My truck had just the basic sound speakers. But the access is easy to get to IF you're just replacing the factory speakers with a 6x8 woofer. The grill pops off and you can just unscrew them and pop in the new ones without removing the door panel. However, with the component systems you need to take the door panel off of course. There was already a hole for a tweeter in the door panel behind the speaker grille, so i just used it, it was a perfect fit. Probably not ideal mounting location, but I won't have this truck forever so I didnt want to drill holes all in it and route wires and stuff. The crossover was tricky to fit because of how the door panel is made. But I drilled a hole and mounted it in-between the tweeter and woofer locations and it fit fine enough. Since the grille covers that whole area, you can't see the screws I put in. SO for a Ford, this is a good system.......otherwise go get the 6 1/2;s and use an adapter bracket if you have to - because they're more powerful and handle more wattage...... I actually have the Kicker 6 1/2 components in my wife's car, they sound better even though it was a harder install to do. All in all for a single cab pick up, they put out good sound, loud as I can handle anyway and have good highs/mids and okay bass considering I don't have a sub yet. I was actually impressed with it for not having a sub. I put regular Kicker 6x8s in the back doors, easy breezy, took 5 minutes.

Pros: Fits well in Fords and other vehicles with 6x8's - was able to use factory woofer and tweeter holes with no adapters, no drilling. I gave it 4 stars for easy installation.

Cons: Not as powerful as the 61/2 component system Crossover is just kinda big and bulky, without a lot of mounting options. it'd be cool if there was a way to remotely change the db settings on the crossover without having to remove the darn door panel again....or having it mounted externally inside your car. i took the 5th star away for the lack of power handling compared to other sizes of the same product.

Kicker 40CSS684

Written By Chase, Danville Ky on Tuesday, June 25, 2013

Crutchfield Customer Review (What's this?)

I put these in the front doors of my 2004 F150 supercab and they fit great. The rear said they'll fit; I wasn't able to get the whole system in behind the factory grilles. The tweeter is mounted outside and still looks clean. I like great sound (the reason for components in the front and rear doors). I like the way these components sound. They have some good mid level bass but can keep up with high notes as well.

Pros: Lots of range and great sound.

Cons: Didn't fit as well as I had hoped in the rear cab doors; but I'm still satisfied with the end results.


Written By Jason G, Denver CO on Tuesday, June 04, 2013

Crutchfield Customer Review (What's this?)

They are perfect in my case because of their fit in my Ford Fusion. I was able to mount the crossover next to each of the 6x8 for a clean look. Also in a good spot for servicing and adjusting gain since popping off the door panels are easy.

Pros: Sound

Cons: None

"Great Sound"

Written By Mike Y, Hilo, Hawaii on Thursday, May 02, 2013

Crutchfield Customer Review (What's this?)

Simple installation and great sounding results is what I got. Clear and clean.

Pros: Easy installation and great sound

Kicker 40CSS684

Written By Art, Riverbank Ca on Saturday, March 23, 2013

Crutchfield Customer Review (What's this?)

I put these speekers in my wife's vehical, she was very impressed.

Hands-on research

What's in the box?

Download owner's manual

  • Two woofers
  • Two tweeters (each with 35" Wire attached)
  • 2 Crossovers (each with 35" Input wire/ 35" Tweeter output wire/ 35" Woofer output wire attached)
  • 2 Flush mount tweeter rings
  • 2 Short tweeter mounting nuts
  • 2 Long tweeter mounting nuts
  • 2 Back angled tweeter rings
  • 2 Front angled tweeter rings
  • 2 Angled surface mount tweeter housings
  • Twelve 1" Self-tapping screws
  • Two 5/8" Self-tapping screws
  • 8 Speed clips
  • Four 7" Zip-ties
  • 4 Red plastic butt connectors
  • Owner's manual (English/ Spanish/ German/ French)

Product Research


Polypropylene Woofer Cones: The Kicker CS-series speakers feature durable polypropylene woofer cones, resistant to the moisture and temperature extremes found in automotive applications.

Woofer Mounting Applications: While Kicker describes this speaker as a 6x8, it also fits many 5x7 applications. Please check the Crutchfield Vehicle Selector to confirm fit.

Ribbed Polyester Foam Surrounds: The ribbed polyester foam surrounds allow extended cone excursion for additional bass output and higher SPL.

Tweeter Mounting Options: The tweeters come with brackets to allow multiple mounting configurations: flush-mounted, angled flush-mounted (approximately 10°), and angled surface-mounted (approximately 15°).

Tweeter Dimensions:

  Flush Mount Angled Flush Mount Angled Surface Mount
Mounting Height 0.238" 0.563" 1.272"
Depth 0.532" 0.612" 0.554" (screw depth)
Frame Diameter 1.976" 1.976" N/A
Cutout Diameter 1.57" 1.587" N/A
Frame Width N/A N/A 1.688"
Frame Length N/A N/A 1.897"

Crossovers: The component system includes passive 2-way crossover networks for a seamless transition between the woofers and tweeters. The slope is 12dB per octave (both high pass and low pass) and the crossover point is 4000 Hz. A switch on each crossover allows you to set the tweeter output; 0 dB, +3 dB, or +6 dB. The crossovers' input and output wires are attached; the woofer output has quick slide terminals that connect directly to the woofer and the tweeter output has bullet terminals that mate to the terminals on the tweeter wires. The crossovers' dimensions are:

  • Length: 4.595"
  • Width: 2.463"
  • Height: 1.004"

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

Kicker's Yellow Series of amps, speakers and subs gives you the performance you expect from Kicker at a more affordable price. And this year's models are better than ever.

What are the Labs?