Customer Ratings & Reviews

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Customer Reviews

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Nice looking but...

I'm runing 1800 total amp power now so I bought this product to make sure I had enough CAP. When I got it, I removed the old one and put this one in according to the manual and all my light still dim when the bass hits. There was some trouble charging it.

By Ray on May 19, 2009


found this helpful.

Pretty damn good

The capacitor works great. Easy install, however the flashing blue strip at the top can be distracting if visible from the driver seat. That aside, very pleased.

By Hutch on September 19, 2013


found this helpful.

Great Buy!!!

Looks great. Lights up blue - I like the color. You can hook up many small lines to it or a couple big ones with o-ring connectors. Shuts off automatically and turns back on when voltage change occurs. It also has a digital voltage display. And a voltage adjustor. (Not sure in how that affects stereo performance yet though). The light on the front bounces to how much capacitance is being used- kinda cool

By Tecknodude180 on June 5, 2011


found this helpful.

Best ever

I've had a lot of different caps and so far this is the best 2000W/RMS 4500W/MAX this paired with sound stream power cell Voltage stays between 13.6 and 14.8 at max volume this is amazing. The only problem with charging was that I forgot that the resistors get really hot so all ways wear a glove or use pliers.

By Phillip on October 17, 2010


found this helpful.

Good price, excelent performance!!!

Boss has the best cost/benefit in aidio performance!! The number one in audio!!!

By Nelo on June 10, 2014


found this helpful.

Good buy

I bought it because my sound system would dim my lights BAD. Once I put this in I didn't charge it all the way so it wasn't really helping, but as soon as I figured out why it wasn't performing how it was supposed to I discharged and recharged and now it's working great. The blue illumination is awesome.

By Junior_Charger on March 5, 2012


found this helpful.

it works

I have a punch 500x2 and a RF 300x4 on it and it keeps up with them

By na8t on October 28, 2012


found this helpful.

Great deal fast shipping

I love this product it looks and functions amazing it was great dealings

By Jared on December 4, 2014


found this helpful.

Good value

The product was very good ,for the price it was worth it ,its actually the best product i used so far i been shopping yes i would recomend it to anyone and to shop on this website...

By Karamchand poonai on January 15, 2013


found this helpful.


its very sleek. looks good. works well.... well worth the money.

By Ryan on September 16, 2009


found this helpful.

Good Cap Great Price

This cap works great but I had to charge the cap longer than what it states in the manual. When I charged it for 60 seconds the cap had only reached 10 volts and lights dimmed. After discharging and recharging the cap up to 12 volts its been working great.

By Derek on September 30, 2013


found this helpful.

Boss CAP8

i loved the set up of the capacitor. i loved the way the blue went along with the bass of the song. i also love the led digital meter on the cap.

By Kole on September 10, 2008


found this helpful.

do not buy

The pros of this cap are as follows: It looks pretty cool. Thats it in my opinion for any good thing about this cap. I bought it for a 1600 watt system. I hooked it up correctly and it would not charge properly. The feet on the cap are cheap plastic and got all scratched up. There was no discernible difference with the cap hooked up and before I had the cap (light dimming). Finally when I disconnected the cap and followed the dishargeing procedure it sparked and smoked. I went to my local audio shop and the owner said it was tell tale signs of a faulty cap straight from the factory. Spend a little more on a quality cap.

By Zach on September 17, 2013


found this helpful.


this is a great cap took most of my diming away but I am running 2 lanzar 6000 of it so just a baby step

By Henry on September 9, 2013


found this helpful.

great price

I had some trouble charging the cap, but after charging it, it was simple. after i got it all hooked up it looks sweet and looks great too

By Kathleen on April 11, 2009


found this helpful.

Product Review

I had a custom made box for for 2 10's made for my F-150 this cap looks awesome just peeking out from under my seat. Has a light rattle but nothing turning it up can't fix

By Lindsay on March 6, 2013


found this helpful.

Never a problem..very dependable

I personally havn't experienced any of these problems other ppl seem to be having, but as long as you read the directions, charging it shouldn't be a problem at all..
I will admit that my lights seem to flicker a touch when i am stoped, only when low notes hit though.
And as for people saying their lights dim a lot, thats probably because the lights you are looking at are LED's, which if that is the case are much more sensitive to voltage fluctuation, than a incondecent that's just kinda hit or miss, depending on your car. =\

By Stixx77 on August 6, 2009


found this helpful.

Works great

Cheap, good looking and keeps the power stable in my beat down 93 accord. No lights dimming, no alternator / battery fail so im very pleased with it.

By MIKE on January 4, 2013


found this helpful.


I have this along with a SHURiKEN SK-BT20 and my system never drops lower then 13.5v. I'm pushing 1700w rms and my lights don't even twitch! Also the display on it is pretty cool lol it mimics an EQ. Nice product, I would recommend it to anyone.

By Mike on January 16, 2011


found this helpful.


SO good for the price, The battery in my RSX is quite small, this supplement's it well reducing the load on my alternator. Passive mode is super neat. (Shuts off when not needed) Need's a chassis ground to work and remote turn on signal.

By Vaughn on March 4, 2013


found this helpful.

Works well!!

1400rms and it keeps the volts above 11 at max level for my system. No lower price than at Sonicelectronix.

By Clarence on January 18, 2010


found this helpful.


Bought this cap a while back and it works perfectly. Whether or not it is actually capable of 8 farads who knows, but it is doing all the work I need it to. The blue backlighting is also a plus.

By Josh on May 14, 2012


found this helpful.

Good product

All parts that I bought work properly exactly what i was needing thank you sonicelectronix plus i got a great deal
Transactions were safe shipment on time
Thank you again!!

By Oscar on June 29, 2015


found this helpful.

Great price and product

The best for the price stop my lights from dining if u follow instructions

By Zay on April 15, 2016


found this helpful.

Need that extra voltage

The boss came through for my 2x12 subs pioneer setup. helps me maintain voltage.when my deep bass hits

By David on February 26, 2017 checkmarkIcon Verified purchase


found this helpful.

Great product

Easy to install and was a great price with on time shipping.

By jeff on December 11, 2020 checkmarkIcon Verified purchase


found this helpful.

bonne achat

j'ai acheter se produit et pour le prix il en vos vraiment la peine

By smiley_boy on January 18, 2016


found this helpful.

By Troy on June 29, 2023 checkmarkIcon Verified purchase

Fire Hazard

Had the Boss Cap8 installed in my vehicle and working fine for 3 months before it blew a fuse and started smoking. The manufacturer offered me a replacement as long as I paid the shipping and customs to the US which would cost more than the product. Not recommended!

By Mark on March 17, 2023

This cap works great!

Must say this cap works great! The last cap I had the spl the studs broke loose from the housing. This one is alot better design and looks like it will hold up just fine. My lights don't dim at all even on the hard hitting bass. Looks good too!

By Spankie on September 3, 2016 checkmarkIcon Verified purchase


found this helpful.

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