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Infinity Reference X REF-4002cfx

4" 2-way speakers

Item #: 108R4002CX

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8 Reviews | Ask Questions


Price Break:-$40.00

Installation gear for most cars

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REF-4002cfx 4Designed for more clarity

Do you want to hear the details you've been missing in your car's sound system? You'll enjoy exceptional clarity from Infinity's Reference X Series REF-4002cfx 4" speakers. Infinity uses textile dome tweeters to give you amazing levels of detail without sounding harsh; each tweeter features a level control switch so you can boost the brightness to your taste.

Larger woofer for more bass

The REF-4002cfx features tough polypropylene woofers and durable hi-roll rubber surrounds that deliver strong performance. Each Plus One+ woofer sports a significantly larger cone than speakers of similar size, adding plenty of punch to the speaker's smooth and accurate highs.

Great for any power supply

You can power these speakers with up to 35 watts of RMS power — they'll work great with an external amplifier, but they're also sensitive enough to be a good match for a factory or aftermarket stereo. Plus, Infinity comes up with a safe way to get a little more power out of your system — these 3-ohm speakers combine with the speaker wire in your car so your car stereo sees actual 4-ohm impedance. Grilles are not included — factory grilles are appropriate for most installations.

Product Highlights:

  • 4" 2-way speakers (pair)
  • Plus One+ Injection-Molded Polypropylene (IMPP) woofer cone with hi-roll rubber surround
  • 1" edge-driven textile dome tweeter
  • True Four Ohm Impedance technology: speaker's 3-ohm impedance combines with speaker wire impedance for a 4-ohm load
  • compatible with virtually all factory or aftermarket car stereos
  • power range: 5-35 watts RMS (105 watts peak power)
  • frequency response: 75-21,000 Hz
  • sensitivity: 92 dB
  • top-mount depth: 1-7/8"
  • warranty: 1 year
  • Our 60-day money-back guarantee

Infinity Reference X REF-4002cfx Reviews

Average Customer Review:

8 Reviews

Infinity Reference X REF-4002cfx

Written by: toocool802 from California on December 9, 2015

1992 Toyota Celica
Crutchfield Customer Review (What's this?)

nice sound well fit



Infinity Reference X REF-4002cfx

Written by: Renny from West Virginia on March 3, 2015

Crutchfield Customer Review (What's this?)

Great sound, perfect fit. Installed in Kubota L5240 with cab. Plug on pigtail connector would have been nice.



Infinity Reference X REF-4002cfx

Written by: Randy W from Chapel Hill, NC on February 4, 2014

Crutchfield Customer Review (What's this?)

Great sound !!

Pros: Excellent sound

Cons: Depth of tweeter was too high for factory speaker grills on 1991 Toyota Celica. I had to sand down inside of grill to fit...

Infinity X REF 4002cfx

Written by: SteveM from Emigrant, MT. on October 17, 2013

Crutchfield Customer Review (What's this?)

I put them on my motorcycle- BMW 1600GT as the stock ones leave a lot to be desired. Really added range and depth to the music, worth the price. While I had to do a little modification ( very simple ) they fit nicely and glad I bought them.



Review for the Infinity Reference X REF-4002cfxx

Written by: Jeff M. Foster from Olympia, WA on August 2, 2013

Crutchfield Customer Review (What's this?)

I have been a great fan of the Infinity Reference series speakers as I have now installed them in all three of our cars. However, the last two purchases I have made of Infinity Reference speakers, I noticed that the company is now owned by Harmon. The speakers still sound great and are of top quality but you can no longer install the speakers without additional purchases. On the Infinity Reference 6030cs component speakers, I was missing a pair of "+" and "-" speaker wires with Infinity's top quality insulated connectors even though the instructions showed 3 pairs of wires. I called your customer service to find that only two pairs of speaker wires were included in the box. On the Infinity Reference X REF-4002cfx speaker purchase, there wasn't any mounting hardware, speaker wires or speaker grills included. (Speaker grills would have made my installation a lot easier.) When you spend this much money on a pair of speakers, everything for the installation should be included. This would have saved me a lot of time. That said, this will probably be my last purchase of Infinity Reference speakers. It's not worth all the aggravation!

Pros: These speakers have great sound and are of top quality.

Cons: The mounting hardware, speaker wires and speaker grills were not included with the purchase. For what I paid for these speakers, these items should have been included. I would not recommend purchasing these speakers even though they sound great!

Infinity Reference X REF-4002cfx

Written by: rex r from Custom Auto. Loveland, Colorado on July 29, 2013

Crutchfield Customer Review (What's this?)

These are great speaker and easy to install we are putting them in a 1934 Ford coupe. while it will be a few months before we preform the final hook up of these we have never been sorry with any product that the Crutchfield team has recommended for our car.

Pros: Great speaker to fit inside a small early Ford coupe.

Cons: Didn't give it a full five stars we have yet to try them out.

speakers and customer service

Written by: larry from jax fla on April 20, 2013

Crutchfield Customer Review (What's this?)

the speakers work great and fit well but the service was the best i have seen in online purchasing thank you crutchfield



Infinity REF-4002cfx speakers

Written by: TomV from Long Grove, IL on July 5, 2012

1986 Porsche 911
Crutchfield Customer Review (What's this?)

Bought to replace pair of blown (not original) speakers. Installation was no problem. Sound is very good. Only gripe is that speakers lack a grill; will have to try to retrofit an old one or find a universal speaker grill.


Cons: No speaker grills, unlike others in the same line.

Hands-on research

What's in the box?

Download owner's manual

  • Two 2-way speakers
  • 2 Adhesive backed foam gaskets
  • 2 Infinity logos
  • Template on box
  • Owner's manual (English/ Danish/ German/ Spanish/ Finnish/ French/ Italian/ Dutch/ Polish/ Portuguese/ Russian/ Swedish/ Turkish/ Chinese)

Product Research


Plus One+ Woofer Cones: Each speaker uses a cone significantly larger than other speakers of the same size. This is accomplished by using a unique basket design and hi-roll surround. The Plus One+ design offers greater bass output and an increase in efficiency.

Hi-roll Rubber Surrounds: The hi-roll rubber surrounds allow the woofers a greater range of movement, resulting in longer X-max and more bass output.

Textile Dome Tweeters: Each speaker uses an edge-driven textile dome tweeter for smooth, accurate highs. A switch on the housing allows you to adjust the tweeter output; choose 0 dB or +3dB, useful if the speakers are mounted low in a door where high frequencies are easily absorbed.

True Four Ohm Impedance Technology: The speaker's 3-ohm impedance combined with the impedance of your speaker wire provides a true 4-ohm load to your connected head unit or amplifier.

Power Handling: Although Infinity rates the 4002cfx speakers at 35 watts RMS (continuous average), they also recommend amplifiers with a power rating from 5 to 50 watts RMS.

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.

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