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Infinity Kappa 680.9cs

5"x7"/6"x8" component speaker system

Item #: 1086809CS

11 Reviews

This item is no longer available.

Original Price: $299.99

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Infinity built their Kappa Series speakers with improved technology and high-end materials to provide you with outstanding sound reproduction. The Kappa 680.9cs component speaker system features 5"x7"/6"x8" woofers with responsive woven glass-fiber cones that won't flex during a hard workout. The Plus One design offers a larger surface area for improved low-frequency output and efficiency, while longer voice coils add a little more punch to the bass. Large magnets keep the woofers running cooler by placing more steel close to the voice coils to act as a heat sink.

Textile dome tweeters
Infinity uses the same textile dome tweeters found in many of their popular home speakers with this Kappa system, so you'll hear the music the way it was recorded with minimal coloration or distortion. The tweeters handle down to 2,500 Hz, almost an octave below the tweeters in many systems, so you'll hear more definition and detail, no matter where you sit. Infinity includes mounting hardware to install the tweeters in custom or factory openings.

Premium crossover networks
The computer-optimized outboard crossover networks employ audiophile-grade components to separate highs and lows, so that the woofer and tweeter work together perfectly. You can attenuate tweeter response by 6 dB to get the perfect sonic balance if you've mounted the tweeters in a less-than-ideal factory location.

Pre-wired crossovers eliminate a time-consuming step in your installation, and terminals at the end of the crossover wires screw directly to the Kappa woofers and tweeters, leaving no chance for incorrect wiring.

Important Note: Grilles are not included — factory grilles are appropriate for most installations. These Infinity Kappa speakers use a low impedance design to pull more power safely from your car stereo or amplifier. This design is compatible with virtually all factory and aftermarket stereos.

Important Note: You should use an outboard amplifier to power these speakers.

Product Highlights:

  • 5"x7"/6"x8" component speaker system includes woofers, tweeters, and crossovers
  • True Four Ohm Impedance technology: speaker's 2-ohm impedance combines with speaker wire impedance for a 4-ohm load
  • Plus One® woven-glass-fiber woofer cone with hi-roll rubber surround
  • 1" ultra-high frequency textile dome tweeter with I-Mount™ and Starfish™ for multiple mounting options
  • 2-way external crossover network with tweeter level adjustment
  • direct-connect crossover dongle
  • power range: 2-90 watts RMS (270 watts peak power)
  • frequency response: 40-35,000 Hz
  • sensitivity: 93 dB
  • woofer top-mount depth: 2-1/2"
  • warranty: 3 years
  • 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.

Infinity Kappa 680.9cs Reviews

Average Customer Review:

11 Reviews

Great speakers.

Written by: Mike M. from Independence IA on July 10, 2012

These speakers are great, Although i feel i must point out one major flaws the tweeters have. Each tweeter has two terminals, now i dont know about you but that sounds incredibly convenient besides the fact the screws take an Allen wrench the size of a toothpick. After a hour of constant turning on one tweeter i finally got it opened and put the wires into it only to have to re screw them in again. The 2nd tweeter i couldn't even get opened, in the end the wires slipped out of the first tweeter so i ended up just jamming the wires into the tweeter and tapping them in place. In the end it took me about 2 hours just to get the tweeters finished.

Pros: Great sound Very loud Beats out any kicker speaker ive owned in the past

Cons: Tweeter terminals Didnt come with wires I will probably be deaf in a few years

Pretty good sound

Written by: kalyson from sacramento, ca on June 8, 2012

Crutchfield Customer Review (What's this?)

These speakers sound pretty good for the price. The tweeters have a surprisingly low impedance. They are a bit harsh for our ears, but some people might really like lots of treble. We have a Ford F150 XLT 2012 and the tweeter locations are in the windshield pillars. This does not work well at all with these speakers since it will blast lots of treble right into your face. Plus, the tweeters are too far from the other speakers. (Bad Ford!) If we had to do it over again, we'd place the tweeters lower near the other speakers in the door. As it was, we dropped the setting on the tweeters down by 6db (this is an option it has) but that still was not enough. Still too harsh. and unbalanced. Then we installed resistors inline with the tweeters to reduce the input to them -- that seemed to work pretty well. The speakers overall have a pretty good sound, especially for the price. Not sure I'd go with them again, but we are reasonably happy with them now. Note that installation of these tweeters in the original factory location was rather difficult since they are a lot bigger. The holes had to be drilled out and modified for them to fit.

Pros: Reasonably good sound, not too expensive

Cons: Tweeters a bit harsh and difficult to install on our vehicle.

Absolutely The Best

Written by: Joe Davis from Northwest Indiana on April 30, 2012

I have had 2 sets in different cars. These speakers are amazing. There are none better. The clarity is outstanding.

Pros: Amazing clarity

Cons: Not the cheapest but it still was a worth while investment.

Go for these!

Written by: RayD from Jacksonville, FL on July 28, 2011

2004 Mazda Tribute
Crutchfield Customer Review (What's this?)

Installed into a Mazda Tribute (same as the Ford Escape) front door panels. The website says they won't fit, but with a single ply of Dynamat behind them, I have a ¼ inch clearance! Let me say these are well worth the money! I'm only pushing these with 20 clean watts and they sound like they have 50 going to them! The tweeters put the sound stage right in your face! Great components. The crossover is a little bulky and is a showpiece by itself. Mine is in the door and I could stand for something smaller, but it works. The woofer is strong, solid and sounds GREAT! I first went with the 50.9cs- don't waste your time if you're looking for any sort of bottom end. Nice mid sound, but NO bottom at all. Go for these and they will not disappoint!



Infinity Kappa 680.9cs

Written by: Tim G from willowbrook il on March 2, 2011

1996 Dodge Caravan
Crutchfield Customer Review (What's this?)

First set i ordered came with a blown tweeter.Just installed the second set,so far so good.Customer servive is always outstanding sent out another set in 2 days with a prepaid return for UPS.Speakers sound awesome make sure to use a good amplifier to gets the most out of them.



Giant tweeter

Written by: Wesley from Texas on January 14, 2010

I have a 2001 4-dr f-150 and initially purchased the current model infinity kappa 5x7 coax speakers for front doors. Then decided to move those to the back to install these kappa 5x7 components for the front. Once I received the kappa 5x7 components I noticed the tweeters were almost as big as hockey pucks (I'm exagerating, but they really are bigger than I expected). Also the kappa tweeters are painted silver and don't look good. I know I know, I am commenting on the looks of high quality speakers, but I didn't want it to look bad. So I returned the kappas for these reference 6830s. After spray painting the Reference silver plactic tweeter mounts black it looks much nicer. The reference 5x7s sound less full than the kappas that used to be in the front but are now in the back. The highs sound fine but the mid bass is thin and doesn't hit as firmly compared to the kappas.

I like the 2-ohm (actually about 2.4 ohms as tested by my multimeter, probably to prevent rendering stock head units unusable) feature of both the kappas and references. The lack of mid bass is not that big of a deal but is a little disappointment, my kappa coax 5x7's mounted in the rear doors and my 10" kicker solobaric make up for it but I'd rather it come from the front for a more well rounded sound. If you can handle the price difference and the more extreme looking kappa tweeter then I would opt for these kappas, but the look of the kappa tweeters was too much for me.



Exceptional Speakers for the price

Written by: Stephen from Salt Lake City, UT on November 12, 2009

I was working for a car audio dept. at the time I purchased these speakers. I was really amazed with the Infinity Ref speakers they sold so I decided to step up and purchase these Kappa speakers for my car. I was powering them with an Alpine V12 mrv-f345 at the time. Which produced 100W x 4 @ 4 ohms. and as you can see, these speakers run off 2 ohms. So you can do the math and see that I was sending them 200 Watts a piece. Those speakers could really take the power and they sounded AMAZING.
I have a new car now and would really love to put those speakers back on, however I'm going to have to go with a different brand because I don't want to send 200 W to these speakers again. It doesn't sound like a smart choice.
I would definitely recommend these speakers if you don't have a very powerful amp since they run off 2 ohms. These speakers provide such a crisp clear sound. I swear Infinity has the best tweeters in the industry for the price. If you do get these speakers make sure to also get a sub seeing that they're not know for providing those low end sounds. If you have no interest in getting a sub, go for Alpine speakers.
Hope this helps.



Simply Amazing!!!

Written by: Nathan from TC, MN on October 19, 2009

I bought these for my Mustang and powered them with an Alpine F300, and wow do they sound amazing. Don't go cheap and get the References, these sound so much better. I have them set at -6dB on the crossover, which sounds absolutely perfect to me.



Excellent Speakers

Written by: John from Snohomish, Wa on May 27, 2009

2009 Mazda 6
Crutchfield Customer Review (What's this?)

These speakers replaced the factory installed Bose car door speakers (with the micro magnets) in my new Mazda 6. I achieved a large improvement in sound quality. But, I have to second what a lot of reviewers have been saying. The tweaters initially sound a touch shrill. But that seems to go away after a while of use. The base is good, but a subwoofer is recomended if you want impresive base. But my overall opinion is that these are excellent speakers.



Great Sound

Written by: Josh from Morganton on February 10, 2009

These are really a good set of speakers. I've got 2 pair in my truck and they are amazing. Except for there bass handling little weak for some 6X8s but thats what the 1200 watt subwoofer is for anyway



Amazing sound

Written by: Richard from Portland, OR on June 10, 2008

1991 Lincoln Town Car
Crutchfield Customer Review (What's this?)

The moment I got these speakers in the mail I had them installed. I hooked them up to a Rockford Fosgate Power series 4 channel amp, and the clarity of the sound is astonishing. I couldn't be happier than I am now with my Infinity Kappa's. Crutchfield is a great place to purchase your audio gear from.



Hands-on research

What's in the box?

Download owner's manual

  • 2 Woofers
  • 2 Crossovers
  • 2 Tweeters
  • 2 Flush-mount cups
  • 2 Threaded flush-mount adapters
  • 2 Plastic locking nuts
  • 2 Surface-mount cups
  • 2 Starfish tweeter mounts
  • Fourteen 5/8" Self-tapping screws
  • Six 3/8" Flat head screws
  • Two 3/8" Bolts
  • 4 Washers
  • 1mm Allen wrench
  • 2 Adhesive backed foam gaskets
  • Instructions
  • Warranty information

Product Research


Plus One Woofer Cones: The Plus One speakers use cones more surface area than other speakers of the same size. This is accomplished by using a new basket design and hi-roll surround. The Plus One design offers greater bass output and a significant increase in efficiency.

Woven Glass Fiber Woofer Cones: This woven-glass-fiber material is very light and extremely stiff, minimizing cone flex. This results in very low distortion and improved clarity. The woofers have set screw input terminals that will accept up to 10 gauge bare wire.

Edge Driven UHF Dome Tweeters: Each speaker has an Edge-driven UHF dome tweeter. The benefit is increased power handling and reduced distortion at high output. This technology also allows for better integration with the mid/woofer. The tweeter wire terminals are set screws, tightened using the included 1mm Allen wrench; they accept bare wire up to 14 gauge.

High-Output Design: The high output 2-ohm voice coil design compensates for the high in-line resistance of small gauge factory wiring and extracts every watt from factory receivers, increasing overall system output and efficiency (relative to 4 ohm speakers). The speaker's 2.0-ohm impedance combined with the impedance of your speaker wire provides a true 4-ohm load to your connected headunit or amplifier. The speakers also benefit from increased power when you upgrade the wire and add aftermarket amplifiers, designed to power a 2-ohm load.

Crossovers: Kappa speakers include computer-optimized, voice-matched crossovers, using audiophile quality air core inductors and polypropylene capacitors. The crossover slope is 18 dB/octave. Each crossover has a tweeter output switch; choose between flat and -6dB.

Crossover Connections: Each crossover has set screw input and output terminals that will accept up to 10 gauge bare wire.

Crossover Dimensions:

  • Length: 4-3/4"
  • Width: 3-1/2"
  • Height: 1-3/8"

Tweeter Mounting: The I-Mount tweeter mounting system and Starfish mounting brackets give you several different ways to mount the tweeters:

  • I-Mount Tweeter Mounting System: The tweeters can be surface or flush mounted with Infinity's innovative I-Mount system:
    • Surface Mount: Surface mounting the tweeters involves screwing the surface-mount cup to the mounting location, then inserting and locking the tweeter into the cup.
    • Flush Mount: Flush mounting is made easy through the use of the threaded flush-mount adapter and plastic locking nut. Once a cutout is made, the flush-mount adapter (with the tweeter installed) is inserted into the hole. The large plastic locking nut is threaded onto the adapter (from behind the mounting surface) to hold the complete assembly securely in place. When flush mounted, the tweeters may be angled for optimum response and imaging.
  • Starfish Mounting Brackets: The Starfish mounting brackets allow the tweeters to be installed in factory locations behind the grilles:
    • Surface Mount (behind grille panel): Once the Starfish bracket is trimmed, it is screwed to the mounting surface behind the grille panel. Then, the tweeter is inserted into the bracket and locked into place.
    • Flush Mount (behind grille panel): Once the Starfish bracket is trimmed, it is dropped into the cutout in the mounting surface behind the grille panel. Then, the tweeter is inserted into the bracket and locked into place.
    • Bottom Mount (to grille panel): Once the Starfish bracket is trimmed, it is secured to the underside of the grille panel. The tweeter must be inserted into the bracket and locked into place before the bracket is mounted.
    • Flush Mount (in-dash location): Once the Starfish bracket is trimmed, it is dropped into the cutout in the dash. Then, the tweeter is inserted into the bracket and locked into place.

Tweeter Mounting Dimensions:

  I-Mount Surface Mount I-Mount Flush Mount Starfish Surface Mount (behind grille panel) Starfish Flush Mount (behind grille panel) Starfish Bottom Mount (to grille panel) Starfish Flush Mount (in-dash location)
Mounting Height 1.316" 0.693" 1.328" 0.624" N/A 0.624"
Depth 0.552" (screw depth) 1.311" 0.552" (screw depth) 0.692" 1.370" 0.692"
Frame Diameter 2.216" 2.855" 2.221" 2.221" 2.221" 2.221"
Cutout Diameter N/A 2.360" N/A 2.221" N/A 2.221"

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

Video: Infinity Kappa car speakers
by Robert Ferency-Viars

Infinity Kappa is Infinity's high-performance line of car speakers. They're designed and built to give you excellent sound, especially in an amplified system. Watch as our experts show you why...

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