When do you need a Capacitor for Amps?
 

My capacitor for my amps stopped working after the boats winter hibernation. The stereo still works and sounds just like it did before. I only have two small subs and the bass level is not turned up high. The stereo was in the boat when I purchased it along with the receipt. I don’t know if they installed it to make more money. The guy I purchased the boat from did not know the difference from a Phillips and Flat head screwdriver.:rolleyes:

In addition I want to add another amp, and was going to use the space the capacitor took up if I do not need it.

Thoughts?

I have talked to several Stereo shops recently about putting a capacitor on my system and they both told me to go with the new battery technology instead of the capacitor. I have 2 12" subs and I can watch my voltage gauge dance with the beat with two new batteries and the motor running and 1/0 power cable. They say these special batteries have very low internal resistance and can put out a lot of current. They are supposed to be 100 times better than caps and are only a little more money.

This... Get a better battery. The money you'd spend in capacitors that would actually make a difference is going to be more than running the correct battery for a stereo system. We used to get kids all the time wanting to add capacitors because the box says "1 Farad will protect up to 1000watts".... I used to try and get them to go with a bigger battery and alternator because the caps aren't as effecient as advertised.

They do work...and help stabalize the drain on the battery, but they are only a MINOR improvement. Money would be much better spent on a better battery.

If you are under 1000 watts, I would not even bother with a cap.

x3 MORE BATTERIES!

Caps are moderately effective at flattening the voltage so car lights dont flicker.
The problem is, while engine is running the alt raises battery voltage above the resting battery voltage of 12.8. That means the alt is doing all the work and any requirements above what the alt can provide will drastically drop voltage until the battery actually "kicks in" at 12.8.

This is really not an issue on a boat. most stereo playing is done with the motor off which solely relies on the battery, a cap will have no higher voltage than the battery when off. Even when running, voltage fluctuation is a non-issue. There is a website where the author goes to great mathamatical lengths to prove the general worthlessness of a cap. Even quoting the first user of capacitors in car audio saying it was for show points more than effectiveness.
Look at any bass competion setup today, you will see no caps, just banks of batteries.

Skip the current Battcaps marketing too, in a boat we need MASS storage. Deep cycle. More battery capacity the better. A stereo can play longer with more capacity and batteries will "live" longer if they are not deeply discharged. Fastest way to kill a battery is to fully discharge it every weekend.
A larger battery is better than multiple smaller. IE if you are serious and can hold a 31 or 4D, it will be more effective than a couple 27 series of same total Amp Hour.

If you are frequently crushing the waves at LOTO, a more durable battery like Optima may make sense. Otherwise a good Deep cycle like Interstate will be fine. I have found the Kinetik to be strong, long lasting stereo batteries but costly. I got lucky and picked mine up from a guy who had just installed a system and was going to jail for a while so he was liquidating :lolhit:

Most important - good battery charger, fully charging every night after use and proper maintance year round.

How far are your amps from your battery bank (linear feet of cable distance)?
And what size cable are you running?

These are the two biggest factors not yet mentioned.

This too..... I destroyed a battery running 4 AWG cable from the battery to the cabin. I'm relocating the amp closer (hopefully) to the battery because my lengths I believe are too long for what the amp draws

Actually the real question is, with the stereo playing hard; what is the average voltage reading at both the battery and amp?
IF the difference is more than .1-.2, there is internal resistance, often the rusult of too small power cable for the run length.
The voltage will fluctuate at both points, more batteries will "stiffen" the system and have less voltage fluctuation but what I am asking is measure the average voltage at both points.
Last year I had a guy ask me to check out his system that kept shutting down. He had 12.7 volts at the battery and 9.5 volts at the amp. He had used 10ga house wire! :eek:

The extra current draw of an additional amp may create enough resistance that a larger power wire would be needed.
So additionally, what amps are installed / considering?

Thanks guys!

Cap is going overboard. The batteries only sit 1-2 feet from the amps.

Interesting learned allot:evilb:

When I got my boat, it had 3 old amps, a huge 2F capacitor, and crossovers everywhere. More speakers than I can count. Main wires were braided, at least 1/2" of metal, don't know what gauge that would be. I'm not a stereo guy, and some of the components were shot. I packed out probably 200 lb of crap, and just put a new inexpensive marine head unit, a fairly cheap 1000w Pyle marine amp, and some cheap speakers. No capacitor. Total cost, like $200. Good enough for listening while wrenching, probably won't see much use out on the water.