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BOSS Audio Systems

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

  • Based on 3,024 reviews
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Availability: Only 9 left in stock, order soon!
Fulfilled by Onlinesound
Arrives Sunday, Aug 24
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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


Material: Aluminum, Plastic


Shape: Rectangular


Operating Voltage: 16 Volts


Capacitance Tolerance: 10


Maximum Voltage: 16 Volts


Mounting Type: Car Mount


Manufacturer: BOSS Audio Systems


UPC: 808112576358 791489120302 163121103941 012306024833 100010959227 088020618238 132017998350 102930669125 807032946876 636331251912 070071263789 079532004114 809387598618 803982861849 021112860900 807320291060 168141298561 163121517694 809188503026 012304443452 611101439042 801038840008 115970970724 041114469826 701002645069


Global Trade Identification Number: 02, 58


Product Dimensions: 4 x 11.4 x 4 inches


Item Weight: 6 pounds


Item model number: CPBK3.5


Is Discontinued By Manufacturer: No


Other display features: Speakers


Color: Black


Whats in the box: Capacitor


Department: Electronics


Date First Available: February 27, 2013


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Aug 24

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

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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
    • Good cap and not over priced.
Style: 8 Farad
Review Image by KelvC KelvC
Great item,good price , easy install and it makes any system look . Does its job , no dimming of lights and it’s by far the best cap I’ve had .
Reviewed in the United States on March 24, 2025 by KelvC KelvC
    • Great quality and power for the price! Not just some knockoff brand!
Style: 8 Farad
Great price for such a high Farad Capacitor! 8 Farad provides a lot of wattage protection for your vehicle charge system. Installed in my 2018 Ford F-150 which has a 1000 watt JBL 5 channel amp and a Mono Kicker 400 watt amp for my subwoofers. Was super easy to install and first Charge with included resistor, has well made +/- hookup posts for the cables, and a very accurate voltage display to see the Capacitors voltage charge state. For being an 8 Farad Cap, it’s not very big whatsoever! Nice design as well. Even though truck has a strong AGM battery and powerful DC Alternator, I still wanted to protect all the high tech electrical systems in my truck. Not only does it prevent any light flickering/dimming when playing music loud. It also provides extra boost of power to my amps making my audio system sound even more powerful then it did without the Capacitor. My truck has a big 8” touch screen interactive radio display so I didn’t want to cause any damage to the system. I can crank up my system extremely loud and not worry about any headlight dimming or audio degrading. When purchasing a Capacitor you really have to do your research since there’s so many cheap no name brands on the market that really don’t do anything positive but it only hurt your audio equipment.! If your not careful, you really can damage your equipment doing more harm then good. For the price you can’t go wrong, and a good tip is to always over size the caps Farad rating so your helping your audio equipment and not hurting it. ... show more
Reviewed in the United States on June 29, 2019 by JFM1821
    • So far these subs sound great. I have them set up for 2 ohms ...
Style: 8 Farad
I have had the system installed with 2) NEW Kenwood KFC-W3016PS 12" subs being pushed by the kenwood KAC-9106D 2000 Watt mono block class D amp and thus cap (boss audio cap8 farad). So far these subs sound great. I have them set up for 2 ohms and No issues thus far. Made sure everything was installed to specs and made sure all adjustments were within both the amps and the subs specs. I have the settings moderately low but when turned up it really hits. I installed with a zero gage power cable 4 gage ground cable and 12 inch speaker wires. I also have a custom enclosed fiberglass box with about 1 1/2 to 2 cubic feet in it. If I new how to post pics I would but I don't, so I wont. The cap came with instructions and west very easy to charge and install. The blue lights in the center look great. I still have a little dimming of the interior lights when amp is turned up and system is blasting at its max but not during normal music play at a moderate level. Ovarian all I'm happy with the cap. ... show more
Reviewed in the United States on March 11, 2017 by OMAR
    • Does the job
Style: 8 Farad
Added this in on a 2500w dual 12" subs set up in my daily driver. Works as it should and gave me some wiggle room with tuning. My lights still dim a little bit, but that's other things that need upgrading. Looks nice too! Worth the buy. Will reduce light and cut out by a noticable amount.
Reviewed in the United States on October 11, 2024 by Eric Wolfenbarger

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