20 Farad Capacitor and Battery Isolator

[TrillGates2k6]

So I'm not really a novice at this, however it's been a while since I've built a system this big. I'll start at the beginning. I have a 1999 Honda Accord 3.0 V6. It has a stock 105 AMP Alternator. Regular old Battery from Wal-Mart. Here's the plan, I'm gonna be running a continuous load of about 4,000 Watts RMS with all of my amps. I have about 5 of them. I plan on upgrading to a 240 AMP Alternator (It's the biggest, most efficient one they make for my car); Of course I'll be upgrading all of the grounds and alternator wires to 0 Gauge where I can and 4 Gauge where I cannot. All of the main power/ground wires will be 0 Gauge where possible and 4 Gauge otherwise. I am also buying (2) 120 Amp Hour Shuriken BT-120's that will be connected in parallel for a total of 240 Amp Hours coming from the trunk; Here's where things get a tad bit sketchy. I've seen a lot of people saying that they don't run battery isolators and some saying they do. If I understand this correctly, people who do "NOT" run their audio system with their engine "OFF" can omit the battery isolator and people who "DO" run their system with the engine "OFF" need the battery isolator. I just wanted to clarify that. 2nd question is, if I added a 20 Farad Capacitor to all of this, would it help any? Hinder? or would it do nothing at all? Maybe I'm over thinking this, but I'm just trying to cover all my bases before I start ordering stuff.

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[rfluvinmf 10+ year member]

What does/will your system consist of? With 5 amps, you will be better off getting more batteries, instead of the capacitor. If you're running multiple mono amps, I'd suggest selling them and getting one larger mono. That way you can keep it sweet and simple and not worry about gain matching.

 

[bumpasauras 10+ year member]

the cap is not gonna do much some guys run them as a "noise filter" but other than that ...now if you had 1000 farads.. Then we would be talkin but that's very impractical batts make much more of a difference

 

[bumpasauras 10+ year member]

Can't imagine why you would need 5 amps unless you have a monster build.. Although I'm running 4 right now lol

 

[TrillGates2k6]

So I'm gonna be running (2) Hifonics Brutus BRX2000.1D's (2) Hifonics Brutus BRX-6404's and (1) Hifonics Brutus BRX-320.4; I've redone this thing about 3 times already, this is the best I can do; I was actually able to omit (1) amp already, there was (6) amps to start off with; The big amps, there will be (1) per Sub; I have 8 Tweeters that are about anywhere from 50w - 70w RMS (4 ohm); and I just thew an additional (2) 6X9's in there because I want a total of 4 running across my rear deck; I'll have (4) 3-way 6x9's connected directly to the head unit; And i think that's it. But that's as skimpy as I could make it

 

[jumpshowhigh]

If you do go with an isolator, the only one worth a sh*t is the Perfect Switch. Uses MOSFETS and has so little voltage drop, I can barely read it with my meter.

 

[vibe]

with those brutus dont expect to get all 4k out of them. there not effiecent enough to do that. i would think maybe 3500w. and just be careful hifonics amps in my opinion are very power hungry for what they put out. ive had 3 of them and all of them were like that. a good rule of thumb that i just learned is your going to want 55ah of battery juice per 1000w. so with those 2 batterys you good on that end. but like i said just watch your voltage with those brutus. good budget amps just POWER HUNGRY.

 

[TrillGates2k6]

Yeah, I don't really expect to get all the power out. But I've seen a vid on YouTube and Steve Meade bench tested an 1800 watt Brutus amp and he made it do over 2000 watts; I'm pretty sure I can get really close to the advertised RMS wattage. As long as I get close, I'm good.

 

[Jeffdachef 5,000+ posts]

Yeah, I don't really expect to get all the power out. But I've seen a vid on YouTube and Steve Meade bench tested an 1800 watt Brutus amp and he made it do over 2000 watts; I'm pretty sure I can get really close to the advertised RMS wattage. As long as I get close, I'm good.

Thats the amp dyno where a .5 ohm load is actually a half ohm load. in real world situations you will have impedance rise which will make you land somewhere between 1.1-1.7 ohms. Trust me i have a brx 2400 and the impedance rise totally kills your power output. Make sure your always above 14 volts and that your alternator comes from a reputable company. Not some ebay amazon junk. Throw that capacitor idea in the garbage because thats where all normal run of the mill capacitor belong. Ultra and supercapacitors are another story.

 

[Jmez36hz]

I would leave out the capacitors as well. And agreed that you would be better off getting one big more efficient amp rather than a slew of smaller amps. My only other suggestion would be if you weren't planning on it already, when you do your alternator upgrade make sure you run a ground for it in addition to the upgraded alternator return. Strengthened my voltage considerably. As far as the battery isolator goes, I would try and replace your front battery with another agm and just go all parallel. I would think that will also make your alternators life easier. And ya, those brutes are great bang for your buck, but are a bit of a power hog. The higher the efficiency on an amp the more power you get out your speaker terminals with lower input power. The wasted power is emitted as heat..

 

[TrillGates2k6]

Yeah man, I'm already in the process of replacing all of my alternator's power and grounds with either 0 or 4 gauge; And the same goes for the battery terminals under the hood; I would get 3 of the same batteries and just run them all parallel, however that would probably not be the best option for me being that I'm going to be playing my music a lot with the vehicle off; I'd rather have 2 dead batteries than 3 dead batteries. But definitely running the 3 of them parallel would be less strain on the alternator; The reason I'm running 2 separate sub amps is for one, I want to be able to push 4000 watts RMS and I don't know of any amps right off the bat that can do that, and also have rave reviews. I'm not saying they're not out there, but I like to stick with what I know. Secondly, I don't want a single point of failure; If my amp to my subs goes out, I'd rather at least still have one sub working rather than both of them not working; So that's the reason for the multiple amps. Just eliminating single points of failure as much as possible and reducing the strain on the amps in general

 

[TrillGates2k6]

Thats the amp dyno where a .5 ohm load is actually a half ohm load. in real world situations you will have impedance rise which will make you land somewhere between 1.1-1.7 ohms. Trust me i have a brx 2400 and the impedance rise totally kills your power output. Make sure your always above 14 volts and that your alternator comes from a reputable company. Not some ebay amazon junk. Throw that capacitor idea in the garbage because thats where all normal run of the mill capacitor belong. Ultra and supercapacitors are another story.

Yeah I've already dubunked the whole capacitor theory; Never will buy another one. And I'll stay at 14 volts hopefully with all of this research I'm doing; I'm buying a MECHMAN Alternator; They're the best from what I hear. So I should be ok. I'm probably gonna go with some KINETIK KHC2400 Batteries too; I see they're rated at 128 AMP HOURS which is more bang for the buck versus what I initially was going to purchase. Oh and he got more watts than the amp was rated for while he was just at 1.0 OHM; and when he went to 0.5 Ohm, It wouldn't play, or something happened. He did it again at 0.8 Ohms and ended up getting over 2000 WATTS RMS. But I see what you're saying. I'm not looking to get the exact RMS, but just trying to get as close as possible.