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5 star
53%
4 star
7%
3 star
0%
2 star
27%
1 star
13%



Durability
3.9
Value
3.8
Features
3.9
Design
4.3
Usability
4.4

Customer Reviews

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Waste of money

4 farads? Highly unlikely. I'm using an 1800 watt amp and headlights still dim just as bad if not more. The only thing this is good for is an expensive volt meter. I do not recommend and if I could find the receipt i would return it.

By Mark on September 11, 2012

44 found this helpful


Good deal

Powerful, works and looks great. Easy setup and can handle my amp and subs with ease.

By Joseph on August 10, 2012

44 found this helpful


The best

I got this about a month ago and it looks so good in my car with the dark blue light I couldn't be more happier with it . You could so get this !!

By Brad on April 23, 2014

42 found this helpful


SPL CP-4X

The SPL CP-4X has a nice design, but material seems very fragile. I have this connected with a Precision Power class D with 1,000w rms. My dash lights and headlight still dims when the bass hits. The SPL CP-4X specs states that it can handle 4,000w. I think that this item needs to be reanalyzed for true ratings.

By Kenneth on May 23, 2014

40 found this helpful


spl cp-4x

I got this in yesterday and it works and looks great. Goes great with my 5500 spl gorilla amp and my 2 12" spl gorilla subs perfect combo.

By philly b on February 28, 2012

39 found this helpful


Not much of a difference

I followed the instructions, letter for letter, and it didn't help my dimming headlights at all. I am using it solely on my JL XD600/1 and its hook up with a commercial grade 1/0 AWG ground and 4 AWG supply. I guess its time to upgrade the battery and alternator.

By David on July 30, 2013

40 found this helpful


great compaster

It work real well and it looks great!

By Clinton on December 22, 2011

39 found this helpful


for the squeling noise

it is not the capacitors problem you probably have the audio cable to close to the power supply and or the rms cord try running audio cables on the on the opposite side of those cord and it will greatly help with reducing squeal

By Terrys electrical service on October 30, 2013

37 found this helpful


Great value

Great product no problems at all smooth transaction and quick shipping

By Brad on October 4, 2012

37 found this helpful


Lights still dim very badly

Bought this capacitor thinkig that it would at least somewhat reduce the dimming in my interior and head lights from my 1000 watt rms kicker amp. There was really no difference in the headlight dimming before and after installation, although its supposedly 4 farads. The only really good think about it is that it looks cool.

By Moe on August 5, 2012

37 found this helpful


Great cap for the money!

The first SPL-CP-4X cap I ordered was defective. It would not come up to the battery voltage, and just sat there around 8 volts and beeped and flashed. I sent it back and Sonic troubleshot it and sent me a new one. I have installed the second one and it works great.

Pros:
It's 4 farads for $50 (not too shabby).
My electrical system has no voltage/amp fluctuation even at high volume.
Lights do not dim.
Amp has no strain to sound its best.
Auto shutoff after a few min (no need to advertise to thiefs that you have a system).
Solid construction and good terminals.

Cons:
It's bigger so if you're limited on space, verify the measurements first.
The blue lights are cool, but they are very bright, I put black tape over mine.

By Matthew on July 18, 2012

31 found this helpful


:/

I'm no expert but I think a popping noise coming from the capacitor and a really bad smell coming after the pop is a bad sign, I think this thing just dided on me. :(

By Ralphy on August 26, 2011

33 found this helpful


Great Buy

It's small enough to fit under the seat works well ,nice display , but i would like to see it with a cap over the connections.

By Thomas on September 20, 2013

31 found this helpful


Awesome piece of audio equipment!!

most undoubtedly worth buying. i installed this and am running 1200 rms watts. not only is the frequency response better throughout the bass range but the bass is felt more and more in your ear. also matches my amp!

By basshead on December 1, 2012

28 found this helpful


EEEEEEEEEEEEE :(

The capacitor probably works fine. The lights still dim, but hey I have a stock alternator and battery so the cap isn't expected to totally solve that. I'm here to complain that every time I turn on my stereo it emits this ridiculous squealing noise. It's basically like the noise one of those old TVs makes but times 1,000,000. I've tried adjusting the voltage which is just about the only thing you can do since its the only control. The noise will go for awhile and then stop and then start, varying in intensity. It also only started when the weather started getting colder, but anyways I hate it :)

By Sky on January 23, 2013

27 found this helpful


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