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Boss 8 Farad Capacitor With Digital Voltage Display (Black Chrome)

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What 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 always 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, and the dynamics can vary quickly, going from soft voices to thundering bass notes. These moments are where 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.

Model 2 Farad 3.5 Farad 4 Farad 8 Farad 30 Farad Color Dimensions
(L x W x H)
CAP2B Black 3″ x 3″ x 10.30″
CAP3.5B Black 4″ x 4″ x 11.37″
CAP3.5S Silver 4″ x 4″ x 11.37″
CAP4C Chrome 4″ x 4″ x 11.37″
CAP8 Black 9″ x 6″ x 2″
CAP30 Black 11.38″ x 7.25″ x 3″
In the box
What’s in the Box
  • One pair of mounting brackets
  • 2 ring terminals
  • 2 spade terminals
  • Mounting screws
  • 1 resistor
  • 1 Allen wrench
  • Installation
  • Power up procedures
  • Power down and removal

Product Features

  • 3 Digit Super Bright Blue Digital LED Voltage Display
  • Audible Warning Tone for Reverse Polarity, Voltage Overload and Low Battery Voltage.8 Farads with digital voltage display
  • Voltage Measurement Accurate to + / – 0.1 VDC
  • Automatic Sleep Status When Volume Is Low Or There Is No Voltage Variation Present
  • Capacitance: 8,000,000, Working Voltage: 16 VDC, Surge Voltage: 24 VDC
  • Equivalent Series Resistance: 0.015 Ohm @ 100 Hz / 25°C, Capacitance Tolerance: + / – 10%
  • Dimensions: 9 x 6 x 2, Unit Weight: 5.3 Lbs
  • 1 Year Warranty

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  1. Anonymous says:

    Nice looking, but horrible performer, low readings…. Cap is very impressive looking, but when tested with laboratory equipment, it’s almost a total failure. It’s printed 2.0 Farads on the cap, but when measured on lab standards, it’s a big zero, it reads only 0.4 Farads, and that’s after a 48 hour break in period at 15 volts and 100 complete charge/discharge cycles with a 10 ohm load. Don’t trust the over blown ratings. It also has about 50mA current leakage which slowly drains the cap after charging. You better buy at least 5ea of these and…

  2. Anonymous says:

    I measure ~20% of advertised capacity. I just tested the one that I received. I get 0.4 farad, or 20% of the value printed on the can. It would be analogous to ordering a pint of beer and getting a glass with 3.2 oz in the bottom. I would have considered it a defective part, but others who have gone to the trouble of measuring the actual capacitance of these things seem to be getting similar values. I suspect shenanigans. How can this happen?I bought this part because I needed a pulse power supply in my lab, and quick…

  3. Anonymous says:

    Great capacitor regardless of what people say

Comments are closed.