Infinity KAPPA-90CSX – Top Performer

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If you’re not pleased with the performance of your current car speakers and don’t mind spending some pretty pennies on a new pair of speakers, then the Infinity KAPPA-90CSX is definitely one of the best 6×9 component speakers. These things can really fill a car with their incredible sound quality.


  • Stylish design and rugged construction
  • Produces high-quality, lifelike sound
  • Can easily be fitted into any car model
  • Great power handling and sensitivity


  • You will need an amp for full power potential
  • Pretty steep price tag


The KAPPA-90CSX glass fiber cones are one of the lightest 6×9 speakers on the market, while still maintaining a really stiff and durable frame that boasts greater cone-area than the majority of its competition. The premium materials used to construct this unit don’t just make it a well-built unit, but it also helps deliver incredible audio quality.

These Infinity speakers feature edge-drive, soft textile dome tweeters that help deliver some of the smoothest high frequencies you can ever hear. The equipped large voice coil is what helps maintain low distortion and high reliability when playing music on high volumes by optimizing the thermal power handling.

The KAPPA woofers are equipped with Infinity Plus One technology, which them it to extend the cone to the basket’s edge. This, as a result, allows for more surface area. Generally, the bigger the cone, the more bass you can achieve to make higher frequencies less shrilling.

With 405 watts of peak power and 135 watts of RMS, you no longer have to worry about power handling and the longevity of your speakers. Also, with its high sensitivity of 96 dB, the KAPPA speakers are able to achieve ideal volume with just 5 watts RMS. An overall good alternative for your factory-installed speakers.

Audiophile-grade inductors and capacitors are used to tune the speakers with outboard passive crossovers. This helps get rid of the subpar off-the-shelf type of sound and achieve the best quality possible. The best thing about this system is that it can be upgraded from a 2-way system into a 3-way system with ease – adding Infinity Kappa 20mx midrange speakers.

Just like any product, however, the KAPPA-90CSX suffers from a few cons. They’re a bit more expensive than most speakers within its range. Also, while the overall sound quality is amazing, it doesn’t really deliver the bass you’d expect it to deliver.

Features & Specifications

  • Woofer Size: 6×9″
  • RMS Power: 135 Watt
  • Peak Output: 405 Watt
  • Design: 2-way
  • Frequency Response: 35 – 35000 Hz
  • Nominal Impedance: 2.5 Ohm
  • Sensitivity: 94 dB
  • Connectivity: Wired
  • Detachable Grilles: Yes
  • Top-mount Depth: 3-3/16″
  • Bottom-mount Depth: 3-7/8″

For more 6×9-inch car speakers you might like, click here.

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Last update on 2024-07-24 / Affiliate links / *Image Disclaimer: We use images/data from Amazon Product Advertising API solely on products that link to Amazon. On products with the "Price at Crutchfield" button, we use images/data from as per the partnership deal.

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