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BOSS Audio Systems

BOSS Audio Systems CPBK3.5 Car Capacitor - 3.5 Farad, Energy Storage, Enhance Bass From Stereo, Warning Reverse Polarity Tone, Voltage Overload Low Battery

    • Based on 2,809 reviews
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Availability: Only 8 left in stock, order soon!
Fulfilled by Amazon
Arrives Friday, Jun 7
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Style: 3.5 Farad


Features

  • Capacitance - 3,500,000, Capacitance Tolerance: + / - 10%, Voltage Measurement Accurate to + / - 0.1 VDC
  • Working Voltage - 16 VDC, Equivalent Series Resistance: <0.00195 mW @ 120 Hz / 25C
  • Dimensions - 4 x 4 x 11.4, Unit
  • Weight - 6.4 Lbs.
  • Voltage Display - 3 Digit Bright Red Digital LED
  • Surge Voltage - 24 VDC
  • Audible Warning Tone for Reverse Polarity
  • Voltage Overload and Low Battery Voltage

Description

Included pieces View largerWhat Is A Capacitor?A capacitor is a passive (it consumes but does not produce energy) two terminal electrical component. In building a sound system for your car, you would want to use a capacitor for a couple of different reasons.Why Do I Need One?The main reason a capacitor is recommended is for power reserve. The capacitor stores energy and releases it very quickly to the amplifier(s). How does this help? Music is dynamic, no matter what type you listen to. The dynamics in musical content can vary from soft voices to thundering bass notes. These moments are when the benefit of having a capacitor is heard. The amplifier requires a constant amount of steady power to function efficiently and power the speakers. A capacitor will keep the power going to the amplifier consistent and stabilized, which means a better sounding system. Important: The remote output of the head unit is connected to the remote turn on of the capacitor. The capacitor will not function if the remote wire is not connected to your head unit.SpecificationsCapacitance: 3,500,000 (3.5 farad)Capacitance tolerance: +/- 10%Working voltage: 16VCDESR (equivalent series resistance): <0.00195 mW @ 120Hz/25ºCHead screw terminal type: M6 metric system threadDimensions: 11-7/16” L x 3-15/16” diameterWiring Connections View largerWhat Comes In The Box?One pair of mounting bracketsTwo ring terminalsTwo spade terminalsMounting screwsOne resistorOne Allen wrench

Capacitance: 3.5 Farad


Brand: BOSS Audio Systems


Shape: Rectangular


Operating Voltage: 24 Volts


Capacitance Tolerance: 10


Product Dimensions: 4 x 11.4 x 4 inches


Item Weight: 4.9 pounds


Item model number: CPBK3.5


Is Discontinued By Manufacturer: No


Connectivity technologies: Auxiliary


Special features: Display


Other display features: Speakers


Color: Black


Whats in the box: Capacitor


Department: Electronics


Manufacturer: BOSS Audio Systems


Date First Available: February 27, 2013


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Friday, Jun 7

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • May be long, but if you need a real review its here!
Style: 18 Farad
**UPDATE** - Here we are almost 2 years later. (Normally with the PCX models, they would have FAILED, into permanent circuit protect by 6mo to 1yr)... NOT THESE... I bought a 2nd one for backup, and it's been collecting dust in my attic, cuz THIS CAP IS THE TRUTH! I honestly have more voltage, 14.7 , than when I first installed it. NO strain on my alternator, and only 1 battery replacement in this 2yr period! Caps will usually KILL a battery unless isolated by a relay, and stress your Alt. NOT HERE.. battery had a dead cell... alternator tested just as strong as a new one! Can I give this 6 stars?? This company should have me do a video for them, cuz I see nothing but PRAISE deserved for them. I could NOT be happier thanks to them! If this is available still, stop thinking and BUY IT! Of the 100+ Caps I have EVER owned, this has been the BEST performing, longest lasting, and TOUGHEST one hands down.** (Oh yeah I almost forgot..Never ONCE been into "protection mode!" --- God of Caps under $200!)** Let me start by stating, ive ALWAYS provided an honest and unbiased review here and everywhere i post a product review! So heres my analysis of this Boss 18cap, 18 farad capacitor. Overall? A+ ... NOW... lemme point you to a few indisputable facts about this product. #1. Any novice or pro level car audio or electrical consumer will realize this is NOT 18 farads... in reality its closer to between 5-8 farads. You can test it with whatever meter you want, but the way these are built (Hybrid Capacitors) is a combination of a standard 2-5 farad stiffening cap tied down to an additional circuit board with 8 separate high voltage rail caps much like those found in the Brazillian amps these days. Im not an engineer but the basic expl. Is that the board allows the main cap to exceed its normal storage capacitance by having these smaller caps recharge it much faster and thus creating a virtual bank of reserve power in a loop. #2. Dont be fooled... if you have owned the Power Acoustik pcx30, Planet Audio 20f, or several others that "Resemble" this (look at the connections, not the outside case) then you are correct, YOU DID OWN THIS! its the same cookie cutter design including the pcb board and voltage display. The one thing that sets this apart from the others is that THIS ONE the 18cap uses MUCH LARGER stiffening caps than ALL the rest! That 1 factor makes this SUPERIOR to the other clones. These caps themselves are nearly the same as the 4.4 and 5 farad Rockford caps which were phenomenal. So theres 2 of those to drive the build. Now for power. I am a pro builder and have been for 20 years. Capacitors have their place in audio IF USED CORRECTLY!. *NOTE: If you are trying to make a stock Acura Integra run a true 5k watt amp with 4 15's (eye roll) please leave this page and find your local alternator shop and get your electrical upgraded to a 300a or higher alt., get your Big 3 done, and load a couple XS batteries behind a relay! This will not help you!* **NOW.... if you are in my boat, (ex.) I have a 2020 Honda Crv which is under a spectacular warranty, and ANY modification to stock electrical will VOID my whole warranty, unless honda installs it. I can ADD anything i want but i cant remove anything. The honda CRV comes with a stock 90-120a alternator, but the electrical is maintained by less than 1/3 of that. I am running 2 Rockford T2d212, (1000 rms each) and a Brazilian 3k amp (tested at 3375 rms @ 2 ohms) plus an active EQ and Crossover. Ive got big 3 done, and all OFC 0 gauge run to the back. My voltage sat resting at 12.4 and 14.4 driving. Without the cap, i could hit some mid bass notes (the ones that drain voltage 45-55hz) and if at a light, i could nearly shut the car off if i was at 1/2 tilt. That said, an alternator was not an option (warranty void). Ive tested several of these hybrid caps and out of the ones mentioned above and some others... THIS ONE is the only one that proved helpful!. With this, my resting voltage is 14.5 and my driving voltage is 14.7. I can be sitting at a stop light with headlights on, AC blasting, system at 1/2 tilt, bass knob cranked, windows THROBBING and every car around me PISSED and my voltage MIGHT touch 13... never below 12 unless i am near blowing my subs. Final thought. WE HAVE A WINNER. Excellent design.. small footprint... supplements the variable juice needed to carry my system without invading my warranty commitment. Dont look further... start here.. you will not be disappointed. ***MAKE SURE U CHARGE THE CAP FIRST!!**** ... show more
Reviewed in the United States on June 15, 2020 by Dj beatbreaker
    • Easy install & helps out alot!
Style: 18 Farad
Love installing caps like these, makes it so much easier & looks alot better. Definitely helped fix my voltage from jumping round & was super easy to charge before use as well.
Reviewed in the United States on November 2, 2023 by Michael Cox
    • Neutral
Style: 8 Farad
Review Image by carlos solarte carlos solarte
Funciona normal
Reviewed in the United States on September 1, 2023 by carlos solarte carlos solarte
    • BOSS Audio Systems Cap18 - Power Up Your Car Audio System for Ultimate Bass Performance!
Style: 18 Farad
Rating: ⭐⭐⭐⭐⭐ The BOSS Audio Systems Cap18 is a high-capacity car audio capacitor designed to supercharge your car’s audio system and ensure that your bass demands are met with precision. Pros: 1. Enhanced Bass Performance: This 18 Farad car capacitor provides a significant surge of energy when your audio system demands it, resulting in enhanced bass performance that’s particularly crucial for music enthusiasts. 2. Audible Warning Tone: The built-in audible warning tone acts as a safeguard, alerting you in the event of reverse polarity, voltage overload, or low battery voltage, helping prevent damage to your car’s electrical system. 3. Low Battery Voltage LED: The integrated LED indicator displays your battery voltage, ensuring you’re always aware of your car’s electrical status. 4. Easy Installation: Setting up the Cap18 is straightforward, and it’s compatible with a wide range of car audio systems. 5. High-Capacity Design: With its 18 Farad capacity, this capacitor can handle substantial power demands, ensuring your audio system operates at peak performance. Cons: 1. Size: The Cap18 is relatively large, so it’s important to ensure you have enough space in your vehicle for installation. In summary, the BOSS Audio Systems Cap18 is an outstanding choice for car audio enthusiasts seeking to optimize their system’s bass performance. Its high-capacity design, complete with safety features like the audible warning tone and low battery voltage LED, ensures your system runs smoothly and avoids potential electrical issues. While it may be on the larger side, its performance benefits are well worth the space it occupies. If you’re serious about achieving powerful bass and high-quality audio in your car, the Cap18 is a must-have accessory to supercharge your car audio experience. Highly recommended for audio aficionados looking to elevate their car audio setup. ... show more
Reviewed in the United States on October 14, 2023 by Dustin
    • Excellent product, Great price.
Style: 2 Farad Black
And my local big box store wanted $79 for one that is 1.5 Farad,......GTF outta here. anyway, this particular capacitor does the job to feed 600Watt RMS of juice without making any lights blink. That my friends is pretty impressive to maintain constant bass and no power loss or dimming of lights. The only down side is the fact that the post dont have a covers and if you cross them wires or accidently touch both ends together you are going for a ride. Always handle with care and be cautious. The capacitor is not as big as others for the Farad rating and it works. Note that this is been in one car for 1.7 years and no failure and just got a second for another car. Great price and great product. ... show more
Reviewed in the United States on April 1, 2018 by Pedro
    • Wish I never gave it a chance
Style: 18 Farad
It came in on time and was as listed. Except the 1st one I ordered had a little issue and was defective. So I sent it back got refunded and bought a 2nd one, installed it as directed and also got helpful advice from the people at JL Audio on how they recommend I install it. So after triple checking everything I started up my car. It played nicely for about 7 minutes then it started to dim the lights when the bass hit and next thing I knew there was no more bass as the music continues and smoke barrels out of my trunk before I could even turn it off. Both of my 12's we're fried but nothing else was damaged.. mind you everything worked fine before installation then after installation of this cap18 it distroyed 2 subs that costed me $799.99 each. I tried to call and see if they would make it right with me or even meeting me 1/2 way in the price of the subs but they played dumb and kept saying "yes we can return the item and refund you it's cost no problem..." So if you want to take a very risky chance then by all means but I wouldn't advise anyone to buy this. ... show more
Reviewed in the United States on July 15, 2022 by Jose J Vasquez

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