Low voltage/Dimming lights, please read this!!

[mpyrol]

For all you reading this Mxmissle is well educated and informed, so listen to his advice. I do need to validate a couple of statements I made in the previous post.
Caps are good things; my point was that capacitance has everything to do with plate surface area. A cap 6 inches tall with a working voltage of 20 volts will never test out to one farad.
In the smallest speaker division 156.7 Db was the winning number at the last IASCA world finals, the power I don’t know. I do know the top three were separated by less that 1 Db. One of the top three used a gel cell, cap and factory alternator. I was there.
Missile you are right about all the poor quality of RTA's and measuring techniques. Its a shame to see 155 posted on someone’s windshield and the actually do a 46 or 47.
As far as my goal, it's just a goal, however any number under a 47 will be an embarrassment to me. I will let you know my results per PCRTA whatever they may be. The system will be driven by an amp yet to be determined, but I cannot exceed the capabilities of a new battery and factory alternator. Capacitance will be added as needed.
SPL for the most part has more to do with environment than power. In all bass response is dependent on what many people call transfer function. This transfer function will change according to volume ratios, speaker/box tuning, cabin shapes, and vent efficiencies just to name a few. I think these MX6 cars have a natural environment that lends itself to higher SPL's. I hope I am correct. I have done one of these cars that yielded 150 plus (Legal), but with 2 twelve’s and a 300X2 earthquake amp. I lost track of the car after three shows (150.1,150.9,149.9).
You may be correct about your particular brand of gel cell. I have not used one of the red tops but have tested three other brands yielding poor results. In testing many even educated installers use a digital multi meter. The problem is that it is not fast enough to show you the dip in voltage. I have seen digital meters mounted in the dash that will show steady voltage. After further evaluation with an analog needle type meter you may see the voltage dip. Any dip is bad. I have seen these redtop batteries in many applications and I understand that they are the best. They use a spiral type plate structure that for the most part is superior but not very common.
Let me say that this board is one of the most informative and well maintained of any that I have explored. I congratulate all involved and good luck with it! I know this is getting long and I hate to take up too much space but don't you think a little controversy is healthy?

[mxmissile]

Without controversy, progress would be miserably slow! Besides, as is so often the case, what looks like dispute on the surface is merely disagreement on the details of a deeper issue on which like minds find common ground. All the statements in the posts seen here are valid and helpfull - it is only on the application of certain minor issues that there is room for debate!

You mention the spiralcell battery I brought up as being one of the best. They are great pieces, but the new drycells from other manufacturers using flat plates I feel are far better. I mentioned it only to point out that many gel types are quite durable and long lived, just get the right ones!!

Good point about the measuring devices, for both voltage and SPL - that is a detail too often overlooked and too seldom discussed.

Good luck on your project, it should be interesting!

Which manufacturer are you affiliated with? I have sometimes found it difficult to find knowledgable persons in even the most reputable electronics companies in this industry - your comments here speak well of you and your employer!

[mpyrol]

You are absolutely correct, sometimes it is very difficult to find knowledgeable people in this industry and even harder to find ones who are willing to help. Unfortunately I can not speak about our products or my company specifically. My needs are as most of your readers, just a little help. I figure get a little help, give a little help. Heck I may pick up a buddy or two.

[FE3T]

Just wondering.
Could some one explane too me exactly why is a red top better as a main battery than a yellow top?

I know that a yellow top are better as an extra battery due its abillity too withstand lots of deep discharges without wearing out.

[mxmissile]

As far as I can tell, the only reason to put a Redtop up front instead of a Yellow is that they're cheaper!

I've seen it said that the Red has more starting power, but I've never seen that verified....

Who cares? Get the Stinger Drycell in both spots!!

[zylonx]

1) Neither the stinger nor the Optima batteries are gel cells.

2) The stinger is not a dry cell. This was a marketing ploy to make you beleive it was an acid free battery.

3) Both the Optima and the Stinger are AGM batteries ( absorbed glass mat )

Optima = spral cell AGM
Stinger = flat plate cell AGM

4) Internal resistance

Optima = 0.0028 ohms
Stinger = 0.0031 ohms

5) Spiral cell batteries are more durable in a high vibration environment.

6) If you prefer Stinger batteries they are actually manufactured by a company called hawker energy and are also known as odyssey batteries maybe you can get a better price if you dont buy a relabeled battery.

7) There are 3 types of primary lead acid batteries AGM, Gel, and Flooded

8) The red top optima uses a thinner plate design creating more surface space which in turn creates more starting power if you need proof go to an auto store that sells both the yellow and the red tops and ask the to load test them for you

[Stage36]

id just like to point out that alternators are capable of max output at 2500+ RPM. if you feel the need to add a second battery in the trunk, make sure you ground on the frame or chassis with a larger bolt rather than a body ground. you may even consider multiple grounds. corrosion, etc. are usually overlooked voltage drops. battery terminals, grounds, and connection points should have a dielectric or anti-corrosion measure unless theyre gold plated, sealed, etc...

ive found my fluke meter to be very quick on the scale at the bottom of the screen. quicker than the numbers anyway. in side by side comparisons, its quite a bit quicker than blue-point meters and other 'budget' meters. i guess an o-scope would be ideal.


hope this helps...

[Loud_MX6]

I agree with the last post, too, I'm afriad. I have been into car audio for the past five years and all of my systems have included an "over-built" electrical system but none of the likes of more than two batteries. In my mazda, I have a replacement OHIO power source with an optima starting battery and a SVR 100 deep cycly glass-mat battery in the rear. There are a pair of 1/0 cables comming from my isolator to the rear and a third comming back for an alternate ground to eliminate the ground noise produced by the power source. There are also three stiffening caps just because I know how to get them, put them together, and make them look cool. (three mallory 1.3 farad caps bussed together on custom copper and nickle bars). I have a max draw of 250 amps on my system and have never experienced any electrical failures. I might also reccomend that guys who are new to the whole stereo arena check out "class D" amplilfiers. I have a memphis belle and a memphis 1000D amp. The bell draws 125 amps and max consumption, operates @ 90% efficiency (most class AB amps are less than 50%) and produces right at 1400 watts with balls on the wall. The 1000D consumes a little less and makes 1100 watts. The point I'm trying to make is that you don't need a electrical turbine under your car to get a bumping stereo.

[ptirmal]

Does anyone know what the amp rating is for a 2nd gen 4-cylinder? I just purchased a new, used, memphis belle mb17 which I'll be bridging to run at 75x4 & 600x1. I don't know what the stock alternator can handle but i was thinking about adding a second battery.. What do you guys think?

[overboostedmx6]

from what I've learned for every 1000 watts you need a 1 frad cap, I use Rockford Fosgate only because I love there amps and sub's put out hella power I just bought one T2001bd amp and 3 P3's 12's and I dont have any power lost and I'm running a red top too , as for the dimming lights easyest fix put a big power wire from negative to body of car 0/1 gauge would probly be the best if you plan on going over 1000 watts as for inclosure I'll post picks soon still making it look good, .

[Nick51]

how can you charger a capacitor

[mxmissile]

The 1 farad for every 1000 watts is a rule of thumb invented by companies who market capacitors in order to sell more capacitors, lol. The point about upgrading the wires is a very good one, and one I didn't mention in the original post oddly enough! A very simple way to pick up sometimes over .5 volts right away (a BIG difference in a 12 volt system) is to upgrade the wires running from the alternator to the battery, and the ground straps for the alternator (if applicable) and the battery. Replace the usualy-to-thin-and-always-low-quality factory wires with good aftermarket 4 guage or larger wire, and you'll see an immediate increase in overall average voltage in the system. Excellent idea even if you DON'T have an audio system!!

The proper way to charge a capacitor is to place a resistor/diode (usually included with the cap) across the terminals. With the underhood fuse out, hook up the power wires to the cap, and then the ground wire. Now put the fuse in the main power wire. After a few seconds, go ahead and remove the resistor componant. Good to go!!

[Nick51]

there is no fuse under my hood, theres is one that is on the power wire that gos into the amp, that fuse?? Does it matter what size diode i use, i have a diode that reads Rated at 45 volts/ 9 amps/ 0.4 forward voltage drop, will it work

[mxmissile]

you need either a straight resistor or a diode with a resistive quality. The cap should have come with one...?

As long as the fuse is between the cap and the battery, it's fine for this purpose. That said, if your cars battery is under the hood and your amps are in back, you REALLY need to put a fuse under the hood. If that main power wire gets pinched or burned or shorts for whatever reason, there is nothing between the battery and that short to prevent a full on arc weld until the battery dies, lol. If that happens there will most likely be a fire of not insignificant size, and if it happens wit the car running, your alternator and most likely a number of other very important things will die horrible deaths whether or not the car burns up.

[Nick51]

this is how i got the car, and i didnt do anything with the wiring but after hereing what mxmissile said, i will prolly rewire now