Circuit breaker question

88 CuttyClassic

The Enviromental Hitman
Oct 30, 2001
I decided to go with a circuit breaker over a inline fuse. My question is what size i should get. I have 4 gauge wire running to a dist. block and to two amps and 1 farad capacitor. The one amp has three 25 amp fuses and the other has one 40 amp fuse. I think they are available in 120, 140, and 180 amps. Which one would be best?
I highly doubt those 2 amps are drawing anywhere near 120 amps, that 120 is more than enough........
The correct circuit breaker size will be the one that will safely protect the 4ga wire - not the amps. The 120 is the correct size for 4 ga wire.

well of course the fuse or circuit breaker protects the wire not the amps. But what draws power through the wire, the amps, thats all that I was saying. 88 CuttyClassic, why do you have a distrbution block, why wouldn't you just run your 4 guage to your Cap and then branch off from the cap. I did that in my Dakota, 4 guage to cap, then split off of cap with 4 gauge and 8 gauge to my amps. Just a thought man, the fewer connections the better.

I've gotten so many different answers in how to wire my system from a few boards. the one told me to use a 4 way dist block, one wire to each amp and a third to the cap. also they told me to use a dist block on the ground side too. but i was going to put the cap in before the block, run more 4 gauge to the block and then use 8 gauge from the block to the amps, 8 guage out to the ground block and then back into 4. Any better ideas?
Well, for starters, I'm totally opposed to circuit breakers. If it trips you have no indication as to why. With a fuse it will tell you a little about why it blew by examining it. But, I'm a little old school too.

As for wiring, a distribution block is NOT necessary, but they are nice to use. The 1 farad cap isn't needed but it ads to the visual impact...if you do use the cap, it should be as close as possible to the amps power input as you can get it. As for a ground dist block, you don't need that at all. Ground the amps as close to themselves as possible and use the same size wire as the power wire to each amp. Nothing smaller. Also, if you're running 4ga as a main power feed from the battery to the rear make sure you reground your battery with 4ga (same size or larger) as well.
well the dist blocks clean it up a bit. They are both 4 in and 8 out. the ground from the amps will be 8 into the block and 4 out the block. As for the fuse blowing, i wouldn't know how it blew just by looking at it so it don't matter to me. I'm just tryin to save from buying fuses all the time.
Originally posted by 88 CuttyClassic
I'm just tryin to save from buying fuses all the time.

If you are fusing the main 4 AWG from the battery to the amps, you shouldnt have any problems blowing any fuses unless you have a direct short or an amp or amplifiers that are drawing a high amount of amperage continuously. The 120 amp fuse that you are using should be just fine, just make sure that your power wires to the amps are fused at the correct rating.
Just to add to that I have 4 Hifonics amps putting out 960 watts @4 ohms and in the last 11 years I have never blown the battery fuse. That fuse is just to protect the wire and in essence your car and maybe your life. 4 ga or bigger wire will catch on fire before it breaks.
aww damn, i gotta fuse the power wires again before the amps, my distribution block is a solid block not a fuse block. i'm pulling my hair out, so many different opinions. I need a nice schematic drawn up for my system that i can understand. i tried going to the local sound shops but they tried to beat my head with their prices and they weren't interested in helping me. crutchfield has been a big help as far as their defintions of terms.

new problem, i wanted to leave the port plug in my box so that its a sealed encloser but the volume of the box is two cubic feet and the specs for the sub are like 1.00 to like 1.50 cubic feet for a sealed encloser. would it hurt anything if i left it sealed or should i take the plug out. the sub is an audiobahn 1200x
man oh man

do you always do what ppl tell you to do, why dont you try taking the "port plug" out and hear what it sounds like. Besides, didnt you ask this same question a few weeks ago...
i was askin because when i blew my vega they said it had something to do with my box having the port plug out and i wanted to know would i hurt the sub leaving the plug in even thou the volume of the box is bigger than recommended. I guess its time for me to go buy a book about this stuff and stop bothering you guys.
Originally posted by 88 CuttyClassic
I guess its time for me to go buy a book about this stuff and stop bothering you guys.

Asking questions is not bothering us because this is what this sight is all about "sharing information" :). There are 1000s of books out there about car audio and picking up a few and taking time out to read them will give you knowledge which will help you better understand what it is all about.

Anything that you have to supply 12 volts to needs some sort of fuse which is for safety for your car and equipment. They offer distribution blocks with 4 AWG in and 8 AWG out with blade fuses for what you are wanting to do so no need to pull your hair out ;) .

BTW, you dont have to fuse your equipment if you do not want to but "do you feel lucky"??? :eek:
If you have fuses in the amp, that'll be fine if you don't want to use a dist. block..

Man, the whole port question. I'll give ya some more information since you are still confused. With my experience with subs and boxes, ported sealed, band pass, whatever you want it all depends on how you like your bass. Personally I've always loved sealed boxes. You get that low rumbling bass and it hits real hard too. Ported boxes can hit hard but cant handle the lows ( due to the air moving away from the sub through the port giving the sub no resistance)

As far as specs go, hmm I always take into consideration what volume box a sub should be in but I'm not gonna freak out about it. A good example are a pair of MTX 12"thunderpro's that I bought brand new 4 years back that came in an MTX Factory Full Range ported box. After I started learning more about stereos I wanted to build my own custom box, I built huge sealed box for the 12's out of 1" thick partical board. This box was much more larger than what was recommended for the subs, but it was awesome, lots of lows and hit very hard. all I can say is experimint Take your port blocker out try the sub with differnt songs and see how it sounds ( dont crank the piss out of it)

Do some " testdriving" it wont hurt the sub............