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Infinity Kappa 120.9W

12" Selectable Smart Impedance Kappa Series Car Subwoofer

4.3

(9 reviews)

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Infinity subwoofers have always distinguished themselves clearly from the competition. The Infinity SSI Kappa series subwoofers are no exception and fight on a playing field all their own. Right away the coated glass-fiber cone shows off an air of sophistication and style while offering incredible rigidity that minimizes distortion.

Once you get past the cultured exterior, the interior components uphold Infinities affinity for advanced technology. This Kappa sub utilizes a triple voice coil system which gives it the incredible ability to offer selectable impedance. Selectable Smart Impedance (SSI) technology allows this sub to run at 2 Ohms or 4 Ohms with the flick of a switch. This allows you to extract the most from your subwoofer amplifier in any situation. If you decide to add a subwoofer down the line, SSI makes it easy to reconfigure your entire system without buying different subwoofers or amplifiers.

The SSI Kappa subwoofers handle a remarkable amount of power and sound incredible in sealed or ported enclosures. If you want great sounding bass with unheard of wiring versatility, Infinity Kappa subs are technologically advanced enough to handle it.

General Features:
  • 12" SSI Kappa Series 2 Ohm or 4 Ohm Subwoofer
  • Power Handling:
    • Peak: 1400 watts
    • RMS: 350 watts
  • Impedance: Selectable 2 or 4 ohms
  • Coated glass-fiber woofer cone
  • Thick rubber surround
  • Selectable Smart Impedance (SSI) lets you set the subwoofers impedance with the flip of a switch
  • Cast aluminum basket with voice coil vents
  • Triple voice coil technology
  • 2" Voice coil diameter
  • Rubber boot surrounds the magnet structure
  • Frequency response: 23-400 Hz
  • Sensitivity: 91 dB
  • Authorized Internet Dealer
  • 1-year Manufacturer's warranty
Package Includes:
  • 120.9w SSI Subwoofer
  • Foam Mounting Gasket
  • 3mm Hex Wrench
  • Owner's Manual
  • Technical Data Sheet

Read more about the 120.9W at our blog.

Product History:
Infinity Kappa 120.9W thumbnail
(newest, current model)
Infinity Kappa 122.7w thumbnail
(previous model, replaced by Infinity Kappa 120.9W)
Subwoofer Specifications
Subwoofer SeriesKappa
Subwoofer Size12"
Peak Power Handling1400 watts
RMS Power Handling350 watts
Voice Coil(s)Single
Impedance (Per Voice Coil)2 or 4 ohms
Voice Coil DiameterN/A
Frequency Response23 - 400 Hz
Sensitivity91 dB
Xmax (millimeters)17.50 mm
Subwoofer DesignRound / Circle
Main Cone ColorGold
Woofer CompositionCoated Glass Fiber
Woofer SurroundRubber
Magnet StructureN/A
Subwoofer GrilleNo
Re-Cone Kit AvailableNo
Recommended Enclosure Specifications
Recommended Enclosure TypePorted / Vented
Sealed
Minimum Sealed Box Volume1.00 cubic feet
Maximum Sealed Box Volume1.00 cubic feet
Minimum Ported Box Volume2.00 cubic feet
Maximum Ported Box Volume2.00 cubic feet
Top-Mount Depth6-5/16"
Cutout Diameter11-3/16"
Shallow Mount InstallationNo
Warranty and Return Policy
Return Policy Standard Return Policy
Parts Warranty Duration1 year
Labor Warranty Duration1 year
Warranty ProviderManufacturer
Customer Review Summary for Infinity Kappa 120.9W
Average Customer Rating is 4.3 out of 5 stars:
4.3
based on 9 Reviews
Share your thoughts with others:
Rating Distribution:
5 star:
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56%
4 star:
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33%
3 star:
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0%
2 star:
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11%
1 star:
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0%
what's this?
Average Attributes Rating:
Durability
4.4
Value
4.4
Features
4.9
Design
4.9
Usability
4.9
what's this?
Quick Comparison:
Most Helpful Customer Reviews:
November 24, 2011 Couldn't be happier
Review by
Jacob from San Antonio, TX
Overall
Durability
Value
Features
Design
Usability
I have owned this subwoofer for 4 months and I couldn't have been happier. I can't say anything negative about this subwoofer. There are many great thing about this subwoofer.

1. It works well in a compact box.

I have it in a 1.0cu ft sealed Sonic sub box stuffed with polyfill. Unlike many car subwoofers, this one is actually optimized to work in reasonably small sealed boxes (1 to 1.5 cu ft). WinISD recommends 1.2cu ft when running in 4ohm mode and 1.7 cu ft in 2 ohm mode. I run it in 2ohm mode, in effectively a 1.25cu ft box (due to polyfill), with resulting qtc of about 0.76, which is almost perfect.

2. Good sensitivity and power handling.

Don't worry if you have a modest amplifier. This subwoofer can still get very loud when running off a 250watt RMS power, much louder than is actually necessary IMO. However, should you want to play it a little too loud, I don't see why you could power it with 500w amplifier. Harman Kardon is being obviously modest with subs power rating. The xmax figure alone suggests that this Kappa should take up to around 500watts while still operating in its "SQ" range.

3. The cone looks great.

4. Low Inductance. Most subwoofers have such high inductance that their manufacturers do not even report it. This sub has Le of around 1.18mH which is considered much better than average. Low inductance is generally good for transient response and blending with the front stage.

4. Great sound.

Let's finally get to the core of the review. This subwoofer plays very cleanly and transparently. What I hear is a very clean, robust bass with a good texture. It's good for practically any music genre. Midbass output is higher and cleaner than that of an average car sub, which makes blending with the fronts much easier. Don't be afraid to bump your crossover frequency a little higher. (I have mine at 70Hz, up from 60Hz with previous sub). I could go on to continue building a list of things that this subwoofer does correctly, however, I think it would be much easier to say that it does nothing wrong IMO.

Based on what I have heard so far, most Harman Kardon (owner of JBL and Infinity) subwoofers are very good performers, and this subwoofer is a proof of it. I feel like I have been converted. Should I look for a higher end sub in future, once I become rich and famous, I will probably pick up a JBL WGTI from the same company.
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March 26, 2011 smart subs for audiophile taste
Review by
Beau from Nashville
Overall
Durability
Value
Features
Design
Usability
I have 2 of these Kappas, each being driven with a JL Audio 500/1v2 high-damping amplifier. I have the impedance switch set to 4 ohms on each sub for better excursion control. Let me tell you this, these Kappas reproduce every range of bass like a pro... very detailed yet extremely hard hitting. I have them in a sealed, 1 cubic foot per-sub enclosure, and they handle every bit of the amps' power (gains set at two-thirds) using common sense with the volume control/ bass knob. If you want remarkably precise sound that can still rumble the car very well with enough power, these Kappa's will do the job for sure. The impedance switch is very nice. Make sure your enclosure cut-out diameter is large enough... the mounting diameter of these subs are 11 & 1/8 inches across. You can always sand out your box holes with 40-grit sandpaper to make them fit, but it's some work (and vacuuming dust). If you want superb sound, go with these in a sealed box, they would probably work fine in a ported setup also, but the average person with little experience with boxes who likes tight, accurate bass should be very happy with these Kappas in a sealed enclosure.
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November 20, 2010 Just as good as JL w3v3's... and better for a smaller box
Review by
Bo from Nashville, TN
Overall
Durability
Value
Features
Design
Usability
I have 2 of these remarkable subs in my Camaro. I have them set to 4 ohms, and I'm driving each sub with one JL Audio 500/1v2 amplifier... They handle the power very well, I have each JL amp set two-thirds of the way up. The sound quality is brilliant, and the bass is very deep sounding, even for the 1 cubic foot per side enclosure they are in. These sound just as good (and look way better) as the JL w3v3's- I've owned some before. The switchable impedance makes these subs very flexible... I'll probably own mine till I'm 40 yrs old! The only thing to pay attention to is their relatively large cut-out diameter... They won't fit into the same opening size as the Reference 12"s will (too big across)... So make sure your enclosure can accomodate these big boys. They are solid and weigh almost as much as Alpine Type R's, while being more effecient and clearer sounding. 5 stars on these!
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September 23, 2010 awesome subs
Review by
Mextrom from klamath falls
Overall
Durability
Value
Features
Design
Usability
I bought two of these subs six months ago and they have amazing sound quality! They are in a very small truck box underneath the back seat of a 2006 dodge ram. Total air space per sub is .65 cub inches. I was amazed at how low of a frequency they could reproduce in an enclosure that small! Throughout the whole frequency spectrum these subs are amazing no matter what kind of music you listen too. I am very pleased once again by the quality and design of Infinity. These subs are a great deal and you will enjoy the quality of their tonal reproduction from 28hz up!
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June 15, 2010 good lookin nice sound
Review by
alex from orlando, FL
Overall
Durability
Value
Features
Design
Usability
i powered 2- kappa 12" on a kappa one amp. they sound really good and looks great. I guess there's a manufacturer defect - the coil from the frame to the cone cam off. very disappointed in the subs, but sonic is highly recommended. great service, tracking orders, ease of return.
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View All 9 Reviews for Infinity Kappa 120.9W
Subwoofer Grilles
Protect your subwoofer while making your enclosure look great! These subwoofer grilles are the perfect addition to your new subwoofer.
 ProductPriceAdd?
12" Universal Subwoofer Grille12" Universal Subwoofer Grille
Protect your subwoofer with this aluminum grille that is simple to install.
$9.99
Speaker Wire
Choose from our recommended speaker wire to hook up your amplifier to your new subwoofer. The higher quality of speaker wire that it used for this connection, the better your subwoofer will sound.
 ProductPriceAdd?
15 ft. of 12 AWG StreetWires Speaker Wire15 ft. of 12 AWG StreetWires Speaker Wire
This SuperCable from StreetWires is a noise free link between your amplifier and your subwoofer.
$19.99
20 ft. of 12 AWG Kicker Speaker Wire20 ft. of 12 AWG Kicker Speaker Wire
Kicker uses twisted pair technology and hyper-flex cable to provide you with the cleanest sound and a simple installation.
$24.99
50 ft. of 12 AWG Monster 302 XLN+ Speaker Cable50 ft. of 12 AWG Monster 302 XLN+ Speaker Cable
Monsters exclusive SingleHelix® and XLN® construction result in excellent sound reproduction.
$35.00
Sound Dampening Material
Get the most sound out of your new subwoofer with some high quality sound dampening material. It will keep the road noise out and the music inside the car.
 ProductPriceAdd?
Dynamat Rubber RollerDynamat Rubber Roller
Install your Dynamat with ease! This heavy duty rubber roller is designed specifically to install your Dynamat!
$18.99
Dynamat Xtreme Trunk KitDynamat Xtreme Trunk Kit
Get better sounding bass from your new subwoofer with enough Dynamat Extreme for your entire trunk.
$94.99
Enclosure Accessories
These accessories are designed to help you build the custom enclosure that you have always wanted, or add to the box that you already bought. Either way, these products can assist you in achieving better sound, better looks, and more bass!
 ProductPriceAdd?
20 oz. Bag of Poly-Fil20 oz. Bag of Poly-Fil
Polyester fiber fiberfill adds better bass to your system.
$5.99
16 oz. Can of Adhesive Spray16 oz. Can of Adhesive Spray
Spray adhesive used for adhering carpet to subwoofer boxes without bubbles.
$5.99
Spring Post Terminal CupSpring Post Terminal Cup
Makes adding a spring post terminal to an enclosure simple! Banana clip ready!
$2.99
Binding Post Terminal CupBinding Post Terminal Cup
Use this to easily install a binding post terminal to your subwoofer enclosure.
$2.99
Banana Clip TerminalsBanana Clip Terminals
These high grade banana clips allow you to plug into your banana clip ready terminal for a secure connection.
$4.99
System Optimization and Tuning
Use these items to assist in testing and tuning your new car audio system to perfection!
 ProductPriceAdd?
AutoSound 2000 CD-101AutoSound 2000 CD-101
Low frequency test CD
$12.99
AutoSound 2000 CD-102AutoSound 2000 CD-102
High frequency test CD specifically designed for the set-up and evaluation of sound system imaging and placement.
$12.99
AutoSound 2000 CD-103AutoSound 2000 CD-103
Audiophile reference series test disc for evaluation of all audio components.
$12.99
Main Product
 ProductPriceAdd?
Infinity 120.9WInfinity Kappa 120.9W$129.99
Related products
Infinity 120.9W Sub + 50.9cs and 52.9I Speakers + RE Audio XTX500.5 Amp
12" SSI Kappa Series 2 Ohm or 4 Ohm Subwoofer • 5-1/4" Kappa Series 2-way Component Speakers System • 5-1/4" Kappa Series 2-way Speakers • XTX Series 5-Channel Full Range Digital Car Amplifier

For more information on wiring subwoofers, visit our Subwoofer Wiring Guide: Subwoofer Wiring Guide

Product Summary

Manufacturer: Infinity
Model number: 120.9W
UPC: 050667110451
Weight: 22.00 lbs
Internal SKU: 1209w
Internal product ID: 20027

Price Information

$279.95

–$149.96

$129.99

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Customer Testimonial

This company is excellent. Bar-none, I will never buy any electronics anywhere else as long as Sonic carries it!!

- Shane from Tulsa,OK

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