Down4sound D4S SUPER Capacitor Bank | 500 Farads

(19 reviews) Write a Review
  • Down4Sound Down4sound D4S SUPER Capacitor Bank or 500 Farads
  • Down4Sound Down4sound D4S SUPER Capacitor Bank or 500 Farads
  • Down4Sound Down4sound D4S SUPER Capacitor Bank or 500 Farads
  • Down4Sound Down4sound D4S SUPER Capacitor Bank or 500 Farads
  • Down4Sound Down4sound D4S SUPER Capacitor Bank or 500 Farads
  • Down4Sound Down4sound D4S SUPER Capacitor Bank or 500 Farads
  • Down4Sound Down4sound D4S SUPER Capacitor Bank or 500 Farads
  • Down4Sound Down4sound D4S SUPER Capacitor Bank or 500 Farads
  • Down4Sound Down4sound D4S SUPER Capacitor Bank or 500 Farads
MSRP: $499.99
— You save $150.00



  • 12V Super Capacitor Bank, Max Power 4,000W, 500 Farad
  • Cap bank is shipped NOT CHARGED. You will have to charge it to add it to your system. Don't know how? No problem! Watch this video 
  • Operating Voltage: 12.0V - 16.2V
  • Operating Temperature: -40 - 150
  • Capacitance: 500F
  • Watt Hours: 18.2Wh
  • Max Amps: 10,000A
  • Works with AGM & Lithium Batteries. 
  • includes terminals and screws ( see images)
  • 7" LENGTH x 5" WIDTH x 6" HEIGHT

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Warranty Information

Warranty Information

Your new Down4Sound product is covered by 1 limited warranty if purchased from Down4Sound or an authorized Down4Sound dealer. This warranty does not cover improper installation, accidental damage, misuse, abuse, improper wiring, operation of unit outside of listed specifications, or any product that has been modified or repaired by anyone other than Down4Sound. Your warranty covers defects in materials and/or workmanship ONLY and is not an insurance policy. The warranty only covers the original owner of the amplifier.

All warranty returns must be accompanied by the original sales invoice or receipt. You must contact us to request an RMA number prior to sending any returns via the RMA request form on our website. You are responsible for the cost of shipping your product back to us for warranty examination. If your product is covered under warranty, shipping back to you will be at no charge to you – if your product is replaced/repaired outside of warranty you must pay for return shipping and repair bill prior returning of the product or if no defect is found you are required to pay for return shipping only.

At the sole discretion of Down4Sound your product will be either repaired or replaced when it is being covered under warranty. In the event of shipping damage due to improper packaging on products being returned to Down4Sound the customer is liable for the cost of all damages, necessary repairs, or replacement. Be sure to properly pack your return!

*  Extended additional warranty purchased on amplifiers take in affect from the date of purchase and must also be stated on orginal sales invoice or receipt. 



Refund/Return Policy:


Down4Sound - Hours of Operation

Monday 6am - 9pm PDT
Tuesday 6am - 9pm PDT
Wednesday 6am - 9pm PDT
Thursday 6am - 9pm PDT
Friday 6am - 9pm PDT
Saturday 8am - 4pm PDT
Sunday Closed
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19 Reviews

  • 5
    Supercap 500 Farads

    Posted by Martinus Juan Hinton on Dec 08, 2023

    No more headlights dimming. No more 1 volt plus voltage drop. Will stay in the 14’s. I want another asap.

  • 5
    500 farad cap

    Posted by Bigg Marty on Dec 03, 2023

    No more headlights dimming. Stock alt 150 amp. Kicker amp cxa800.1 on two wdx 2 12 inch subs.

  • 5
    It good

    Posted by Maio on Aug 23, 2023

    I like the down for sound experience

  • 3
    Great super cap bank but..

    Posted by Lowprofile on May 28, 2023

    This super cap bank is awesome & added a huge amount of improvement to my system. I have a 400 amp Js alternator paired with a D3400 under the hood & a secondary D6500 paired with super cap bank. For paying $350 I really think y’all could’ve done a better job by adding more attachments like different style lugs along with a charging light like XS POWER… but the most important thing is a better way to hold the caps together instead of zip ties, just looks ghetto asf and half assed if you ask me. I know im not the only one who thinks this..but other than that I was limited on space so it worked out. Just wish there was more thought out ya feel me??⭐️⭐️⭐️

  • 5
    Beyond expectations

    Posted by Jason on Apr 01, 2023

    Perfect addition to any system

  • 5

    Posted by Jeffrey Sprasky on Feb 07, 2023

    Also bought the d4s 8 amp charger, which was perfect for my standards, these have to be slow charged so I also used a 2.7 volt bulb, it took around 20 hours to fully charge, but I was in no rush and wanted a very slow charge anyway, and it does what it is supposed to do, no more dimming lights, my voltage never reaches below 12.2 I also have the lithium 6.0, and 0 gauge ofc big 3 and ofc 0 gauge front to back with a 200amp alt. No issues

  • 5
    D4S 500 farad supercap

    Posted by Brandon on Jan 20, 2023

    Awesome product. Works great and really impressed on how much it helps with voltage droppage. Only downside is I wish d4s would ship a light bulb resistor with it but other than that it's great.

  • 5
    D4S 500Farad ultracapacitor bank.

    Posted by Skilled1 on Dec 13, 2022

    These are one of the most inexpensive ways to purchase a set of 6 XS power Ultracapacitor banks. They're already bussed and packed in a small footprint. Simply charge them with a 12v light bulb and lithium pulse charger. The light goes out and you are fully charged and ready to install. I have a Salt 8 with an Titan 8 and 500Farad cap bank for each of the 3 positive power inputs. Even an ECU controlled 21 Frontier can hold 12.8v and charge @13.5 . They can be ran up too 16v for those interested in changing their charging voltage. Best investment you can get is a solid electrical system. Your amps are only as good as the power you can supply them.

  • 3
    Super cap

    Posted by Douglas hillman on Apr 09, 2022

    I think it would’ve been real nice when the customer pays $350 if you could add the bolts that go on the top so the customer can hook it up instead of having to go to Home Depot and spend more money to buy bolts.

  • 4
    terminal and charging light not included

    Posted by Jamie Gray on Feb 12, 2022

    Works good but not terminals or charging light.

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