Didn't see the 10f part.

this was my thought process. mixing 2 CCA batteries would not be an issue as they are both 12V and both new so one would not draw from another in any scenario except perhaps running accessories for an extended period with the alt off. the RC being lower on one would cause a mismatch if i drain them all the way but outside of that id think there would be no issue or performance hit by having these 2 batteries. 

 

secondly for caps what i was thinking was to ensure hte amps get smooth voltage, devoid of all spikes and dips caused by other accessories powering up and down or what ever else may fluctuate voltage in my truck. seeing as i have a HO alt and strong batteries i am under the impression that a bank of smaller caps would be beneficial in this capacity. i was reading into rockfords caps as these were recommended to me by a coworker "if you really want to go down that road".  honestly im not sure i do want or need to go down this road, what i DO KNOW is that i want to do everything i can to ensure my new amps get proper and consistent voltage.

 

I know caps are a load on a system and that they take time to recharge and that they can not supply large amounts of power but that's not the ultimate goal is it? there goal is to provide a buffer to smooth out inconsistency in a circuit OR to supply a larger burst charge to power up an electronic (such as your AC compressor on the side of your house or a bank of high voltage lights).

 

ultimately perhaps my setup is perfectly fine as is, perhaps i need to add a second alternator, a third battery, a bank of caps, or some combination of such things. I am looking for a confirmation that what i have is good or if not then what is recommended to bring it to that next level.

 

 

edit: as is my headlights do not dimm so that's a non issue. the truck is a diesel so it uses very little power to keep it going. id say under 40A to run the entire truck excluding my add ons. 

 

the math i found online was to take the AH of your batteries added to 2/3 of your alts output and that would dictate how large of a system you could run. for caps it should be 1f per 1KW is what my coworker told me today but i found online that 1f per 500W is whats recommended. i have not referenced the MECP or loud speaker books yet.

Edited December 20, 201311 yr by ncc74656

The answer to your concerns is to spend time on the install, not buy equipment. A cap will do you NO benefit. None, zero, nilch, nada. Just an expensive BS paperweight.

Don't bother with the MECP, pretty useless. If you need it for work it is one thing, but otherwise not even sure you'll learn anything useful.

its not necessarily required for work but it would help in future jobs and give me more leverage when talking wages.

 

ill be redoing the install over the next 2 weeks. i am not sure i will have time to build a rack yet but i really do want to. ill see how ambitious i get in -20F weather. 

its not necessarily required for work but it would help in future jobs and give me more leverage when talking wages.

 

ill be redoing the install over the next 2 weeks. i am not sure i will have time to build a rack yet but i really do want to. ill see how ambitious i get in -20F weather.

It hasn't even hit -20F yet here...

Hopefully you've done a little more research now and realize how useless a cap is. If not, please do.

this was my thought process. mixing 2 CCA batteries would not be an issue as they are both 12V and both new so one would not draw from another in any scenario except perhaps running accessories for an extended period with the alt off. the RC being lower on one would cause a mismatch if i drain them all the way but outside of that id think there would be no issue or performance hit by having these 2 batteries. 

 

secondly for caps what i was thinking was to ensure hte amps get smooth voltage, devoid of all spikes and dips caused by other accessories powering up and down or what ever else may fluctuate voltage in my truck. seeing as i have a HO alt and strong batteries i am under the impression that a bank of smaller caps would be beneficial in this capacity. i was reading into rockfords caps as these were recommended to me by a coworker "if you really want to go down that road".  honestly im not sure i do want or need to go down this road, what i DO KNOW is that i want to do everything i can to ensure my new amps get proper and consistent voltage.

 

I know caps are a load on a system and that they take time to recharge and that they can not supply large amounts of power but that's not the ultimate goal is it? there goal is to provide a buffer to smooth out inconsistency in a circuit OR to supply a larger burst charge to power up an electronic (such as your AC compressor on the side of your house or a bank of high voltage lights).

 

ultimately perhaps my setup is perfectly fine as is, perhaps i need to add a second alternator, a third battery, a bank of caps, or some combination of such things. I am looking for a confirmation that what i have is good or if not then what is recommended to bring it to that next level.

 

 

edit: as is my headlights do not dimm so that's a non issue. the truck is a diesel so it uses very little power to keep it going. id say under 40A to run the entire truck excluding my add ons. 

 

the math i found online was to take the AH of your batteries added to 2/3 of your alts output and that would dictate how large of a system you could run. for caps it should be 1f per 1KW is what my coworker told me today but i found online that 1f per 500W is whats recommended. i have not referenced the MECP or loud speaker books yet.

 

 

You've already identified the problem with using capacitors and why they don't work for a high current drain system with inconsistent voltage levels.  Even ten .5 farad caps hold a very limited supply of current compared to a battery.  Sure if you charge those capacitors and short them out with a wire you'll get a hell of an arc, but that's a direct short that is draining all the current out of them at one time and it still happens super fast.  In a car audio electrical system the voltage will be dropping .5 volt, 1 volt, and even with a 2 or 3 volt drop the amount of current the capacitors can supply to stiffen the voltage and prevent it from drastically dropping is minimal and then as the rest of the system is recovering the capacitor is a kind of a drain on it as it charges back up as well.  

 

When you read about capacitors and using them as a voltage stiffening device all that information is in reference to DC motor drive systems and things of that nature.  It's one quick hard pull on the system and then constant from that point on.  The capacitor helps there because you're not constantly cycling through the charge/discharge time constants like we do with car audio drains.  The theory and practice works for the industrial world but not for the car audio hobby.

 

Forget the capacitor(s) it/they will be a worthless waste of money.  The voltage will never fluctuate enough to cause any issues for the amps and if it did you would know it from the many other problems with the vehicle with lights, it running, etc.  You're thinking WAY WAY too much into it, or at least into the wrong aspects.  Concentrate on the rest of the installation.

OK. Do we think these 2 agm batteries will be enough for the system or will I need more batteries or a second alt? I still have my 130a factory alt.

What shop do you work at? I drove by a Mach 1 today on your side of the city today that had a similar looking ram outside.

thats mine. large winch on front with a cable attached to the truck.  thats the place.  ive started doing my own remote starts now and am learning a crap load about wiring and now that im seeing what bad wiring performs like i have a much better understanding of how it all works. I need to see how the right and wrong way of any project functions in order to properly understand it and feel like i have a grasp on it. in other words its not enough to say "if you touch these 2 wires together it will arc and trip a breaker" i need to do that in order to fell i fully understand how it all works.

 

we are fully into remote start season now but come spring when we start more on stereo stuff i intend to learn how to fab up amp racks and the like. 

biggest thing to remember with 2 batteries is ground issues. both batteries need same ground potential otherwise the weak ground will not charge correctly and eventually lag behind.

yea, from the factory it came with 2 batteries with 0ga VERY THICK strand wire. i replaced it with some CCA 0ga a while ago.

yea, from the factory it came with 2 batteries with 0ga VERY THICK strand wire. i replaced it with some CCA 0ga a while ago.

 

You may have just DOWNGRADED your ground then.

 

Cars typically use low strand, thick strand gauge wiring but is copper.

Using CCA, you would have downgraded the conductivity.

 

Upgrading any wiring in the vehicle for voltage reasons should be in addition to, not replacement of unless the wire is physically damaged beyond repair.

more power will flow through high strand count than low strand count so the CCA would have been an upgrade. aside from that the factory wires were extremely oxidized and had many holes in the insulation. my starter wires cracked in half when i tried to remove it :/.

Replacing from oxidation is a good reason, but you are wrong about high strand being better.. 

 

In DC or non-high frequency AC, thicker gauge strands have the potential to carry more current because of less resistance.

 

Strands are cylindrical.  Therefore, there are air pockets between each strand.

The more strands, the more air pockets when measuring the overall diameter.

 

This is one main reason why welding cable or automotive cable(SGX) looks smaller than normal car audio cable.

 

I assure you, unless the CCA wire has been oversized to compensate, it is not better compared to copper.

 

Now, are you going to have issues?  Don't know.. Probably not because you will have extra batteries to take the load off the front battery.

 

You can actually use 4-8awg wire as ground up front because this battery, when other batteries are installed, doesn't require a large charge from the alternator because it mainly only supports the vehicle due to distance resistance for your car audio.

 

I

now electrons flow on the outside of the wire (skin effect) so the more surface area of wire you have the more power you can send. the CCA wire is less efficient as it is not pure copper but rather aluminum wrapped with copper so it heats up far faster and has more resistance than OFC due to this and thus can not carry as heavy of a load.

 

this is my present understanding. what is incorrect about this?

Skin Effect ONLY applies to VERY high frequency which is AC.

 

There is no skin effect for DC.

 

Also, this frequency is so high, i do not believe it's even possible to be exhibited on speaker wire either.

now electrons flow on the outside of the wire (skin effect) so the more surface area of wire you have the more power you can send.

Please tell me you didn't learn that at the shop !!

At DC (like your cars electrical system) the current flows through the ENTIRE thickness of the cable. With AC (like sine waves, music, or your home electrical system) the current flows through the entire thickness of the cable at low frequencies. As frequency increases it gradually begins flowing through less of the cable thickness and more towards the surface of the cable. HOWEVER, over the audio bandwidth (up to 20khz) the current still flows through the majority of the cable thickness. Skin effect for our purposes can literally be ignored. It does not exist with DC and with AC, over the audio bandwidth, it is not a factor. It's a non-issue for us. It doesn't become a real consideration until the MHz range (think radio frequencies).

The ONLY thing strand count affects for our purposes is flexibility. It doesn't flow more current. The only thing you need to be concerned with is conductor cross sectional area (other than the difference between OFC and CCA), and no matter how many strands the wire has true 0ga wire will have the same conductor cross sectional area. And conductor cross sectional area can not be measured simply by measuring the overall diameter of the wire in the jacket for multistrand wire like so many people on the internet try to do.

i am reading more into skin effect now. i do recall that DC did not get skin effect but i think i was told at work that i was wrong about that. although i may have misunderstood, trying to take in a lot of information about a lot of things all at once.

Tip-

 

If someone tells you that DC has skin effect at high frequency, turn around and smack them with some 1/0 cable..  

That concept would be scientifically impossible so it would be fun to see, hehe.

i am reading more into skin effect now. i do recall that DC did not get skin effect but i think i was told at work that i was wrong about that. although i may have misunderstood, trying to take in a lot of information about a lot of things all at once.

Skin effect is irrelevant in audio. It's affect on AC over our bandwidth is so minuscule it can be completely ignored. The very fact it was mentioned at the shop is a little scary considering it plays virtually no role in audio signal transmission and for our purposes can literally be ignored. No reason to even be discussing it in relation to car audio.

And then of course there is the fact that it does not affect DC at all.

thats mine.

I should have stopped in to smack that misinformed twit you work for. Perhaps next time I will.

ha, at the very least you could check out our 1200.0 focals, ill even sell ya a pair

ha, at the very least you could check out our 1200.0 focals, ill even sell ya a pair

I've heard better sounds from $40 drivers

lol, im not sure about this driver to that one but i do know the focals are very clear. that said i can not hear a 1000.00 difference from the VERY nice sounding hertz components to the 1200.00 focals. still, some people do spend the money.

I am