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Double Din installation, aftermarket sub and amp too??

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Old Sep 14, 2012 | 10:37 AM
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Double Din installation, aftermarket sub and amp too??

I'm going to do the double din JDM conversion on my 03 coupe and I read about the wiring harness 'problem' with the 70-7551 with the stock amp and not producing good sound quality. Should I just go for a aftermarket sub and amp while I am at it? I wouldn't mind having better sound in my car either. Also, which sub and amp would you guys suggest? Thanks.
 
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Old Sep 14, 2012 | 05:09 PM
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Yes, you should go aftermarket if you're unhappy with the stock sound system.

Recommendations depend on budget, and I wouldn't start with the sub. Get good components up front and it'll be a step up from the stock system in every way, and if you want a sub later, add more.
 
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Old Sep 14, 2012 | 05:20 PM
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Okay, would my route be to get a aftermarket amp and components up front for starter?
 
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Old Sep 14, 2012 | 06:19 PM
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Yeah, new radio, amp and front components should be stage 1.
 
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Old Sep 17, 2012 | 07:06 PM
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This sounds like a great idea ! I kept all my system from my old car. Even having most of the system there is some $$$ involved.....what about a monster cap. It does help to have one right. I mean i do have it...
 
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Old Sep 17, 2012 | 07:39 PM
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Capacitors are worthless for anything but looking cool.

Electricity, current and power draw is a very scientific thing that can be measured, so whatever good you think it could do can be measured as well.

Why caps don't do much good - the extremely short and basic version.

Let's imagine a car with a 12v battery and an alternator putting out 14v. This car also has a 1000watt amp powering some random sub.
We now add a 1 farad capacitor.

A 1 farad cap charged to 14v stores about 84 joules.
Since we have the battery sitting at 12v, the potential (usable power) of the cap is 2v or 12 joules.
We CANNOT use more than the 12 joules, since that would put the cap below the magical 12v where the battery kicks in.

In order to use the power stored in the cap, we would have to turn off the alternator, or the power it outputs would somehow have to drop - like if it's overloaded (BAD).

Note: 1 joule = 1 watt-second. 1000w for one second is 1000 joule.

Anyway, our 1 farad cap has 12 joules of power we can actually use. this translates into 12 watt-seconds. This can power our 1000w amp for 12/1000s of a second, or 0.012seconds.
This means that if we charge the cap to 14v, and turn off the alternator, we can play a single test tone of 83hz one single time before the cap becomes useless.


Since I'm not at all an expert on this, I have neglected to mention ESR and ESL, which would significantly reduce the benefit we get from the cap.
Because of ESR (ElectroStatic Resistance), an amount of power will be converted into heat in the cap. The more power you try to pull, the more heat and the less useful it is.
Additionally, the amp will convert some amount of power into heat - all depending on the amp.

In the end, the cap may give us as much as .005 seconds (single 200hz tone) of power at 1000w amp output, IF the alternator suddenly dies or for some magical reason (it's overloaded, duh) it drops it's output to 12v. If you only run 500W, it would be about 0.01 second or a single 100hz test tone.
So instead of being a shock absorber on your truck, the capacitor is a lot more like sitting on a centimeter of foam in your seat. After everything else has done its best to keep everything smooth, it might just do a little something extra.

And for more in-depth reading: http://www.welcometotheden.8k.com/caraudio/Captest.pdf (you must copy and paste this link, clicking it doesn't work)

Here's a little more math for the cap-crowd:

To get some perspective on how big a farad is, think about this:
A standard alkaline AA battery holds about 2.8 amp-hours.
That means that a AA battery can produce 2.8 amps for an hour at 1.5 volts (about 4.2 watt-hours -- a AA battery can light a 4-watt bulb for a little more than an hour).
Let's call it 1 volt to make the math easier. To store one AA battery's energy in a capacitor, you would need 3,600 * 2.8 = 10,080 farads to hold it, because an amp-hour is 3,600 amp-seconds.
So that 1 farad cap you're looking at? Yes it discharges (extremely) fast, but that energy it has can't even give you more than a nearly imperceptible blip from a sub, since it has less than 1/10,000 of the stored energy of a AA battery, hence why buying a better battery is going to be much, much more effective than a capacitor.
 
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Old Sep 17, 2012 | 08:05 PM
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I'm not interested in upgrading my stereo, but I just learned a whole lot about capacitors lol.
 
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Old Sep 17, 2012 | 08:30 PM
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Pick up a Kinetik, Odyssey, stinger or deka battery instead of a NAME BRAND MARKETING MONSTER CAP

My old setup:

http://www.crossfireforum.org/forum/...plete-wow.html










 
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Old Sep 17, 2012 | 08:52 PM
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Originally Posted by swoo35
I'm going to do the double din JDM conversion on my 03 coupe and I read about the wiring harness 'problem' with the 70-7551 with the stock amp and not producing good sound quality. Should I just go for a aftermarket sub and amp while I am at it? I wouldn't mind having better sound in my car either. Also, which sub and amp would you guys suggest? Thanks.
if your car has the bose system just get the PAC harness so the 'problem' doesn't happen.
 
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Old Sep 17, 2012 | 10:30 PM
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Originally Posted by faiz23
Pick up a Kinetik, Odyssey, stinger or deka battery instead of a NAME BRAND MARKETING MONSTER CAP

My old setup:

http://www.crossfireforum.org/forum/...plete-wow.html










The sad part is, that it's not more power than a 200 farad capacitor, it's more power than a 200,000 farad capacitor, but "power" isn't a really scientific measurement.
 
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