HELP! New JL 10W6V2 Application HELP!

[austinseanchris]

This is my first post guys but to be completely honest, I know nothing about car stereos when it comes to installations/supplies. I've always had custom set-ups in all my vehicles, but never knew what all I needed when it came to parts and what size amps to get for the subs, etc. Well, I've got some new equipment and want to know what I need or if I have too much? Right now, I have an 04 Nissan Sentra with db Polk mid's and highs all the way around ran by a alpine 4 channel amp(unsure of watts). I'm running two JL 10W0's off a MTX Thunder 2 channel(250w I think), both enclosed in the same box. Now, about 4 years ago, I bought my friends two JL 10.5W6V2's and his two JL 500/1 amps. He ran 1 amp per sub and it sounded phenomenal! Now, that being said, he had them in his truck so both subs were in individual truck boxes and were mounted firing down. My question now is obviously I cant use these same boxes b/c they would look dumb flying around in the trunk of my car. I also know the way they hit, they'd bounce all over the place. So do I need to put them both in the same box or do I even need two separate boxes in there? I spoke to one car audio store and they said that 1 was more than enough for that application and that I should sell the other one. Then they started asking how much I'd take for that second sub?!? Obviously, that seemed kinda fishy like someone was trying to rip me off...Secondly, do I need capacitors for each sub/amp? If so, how much in farads do I need? I know I had looked at Fosgate 1 farad capacitors but again, didn't know what the heck I was doing. Lastly, is my factory alternator going to handle this much power or will I need a new one with higher amperage output? I also bought a Rockford Fosgate 1/0 AWG amp power kit that included 17ft of power cable and the ANL fuse holder w/ 300 amp fuse. Is that kit only enough to do 1 amp or will that be enough for the entire car? Is that wiring too big or will it be ok? Any help with this would be greatly appreciated...like I said, when it comes to car audio, I'm out in left field. I just don't wanna get taken advantage of when I go to have all this installed b/c its like another language for me and I'd like to have everything I need for installation and just pay someone to hook everything up. Thanks a million and try to take it easy on the idiot new guy(ME)!//content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

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[SicAudio 5,000+ posts]

use paragraphs i got lost rying to read all that jumbled mess.

 

[jwth2005 10+ year member]

Language arts classes ftmfw

 

[snoopdan 5,000+ posts]

fuckn' 2010ers

 

[austinseanchris]

Thanks for all the help guys...I didnt know I was writing a **** term paper that was to be graded. I would break it down in paragraphs for you but with your shitty attitudes, I'm not wasting my time b/c obviously all three of you could care less about trying to give some helpful information...not even sure why you wasted the time to post on here except to be a bunch of dicks! I'm not even sure why I wasted my time in posting this message...I guess just to show my appreciation! Geez its great to get such great help from fellow car stereo enthusiasts...THANKS!

 

[cotjones 10+ year member]

This is my first post guys but to be completely honest, I know nothing about car stereos when it comes to installations/supplies. I've always had custom set-ups in all my vehicles, but never knew what all I needed when it came to parts and what size amps to get for the subs, etc. Well, I've got some new equipment and want to know what I need or if I have too much? Right now, I have an 04 Nissan Sentra with db Polk mid's and highs all the way around ran by a alpine 4 channel amp(unsure of watts). I'm running two JL 10W0's off a MTX Thunder 2 channel(250w I think), both enclosed in the same box. Now, about 4 years ago, I bought my friends two JL 10.5W6V2's and his two JL 500/1 amps. He ran 1 amp per sub and it sounded phenomenal! Now, that being said, he had them in his truck so both subs were in individual truck boxes and were mounted firing down. My question now is obviously I cant use these same boxes b/c they would look dumb flying around in the trunk of my car. I also know the way they hit, they'd bounce all over the place. So do I need to put them both in the same box or do I even need two separate boxes in there? I spoke to one car audio store and they said that 1 was more than enough for that application and that I should sell the other one. Then they started asking how much I'd take for that second sub?!? Obviously, that seemed kinda fishy like someone was trying to rip me off...Secondly, do I need capacitors for each sub/amp? If so, how much in farads do I need? I know I had looked at Fosgate 1 farad capacitors but again, didn't know what the heck I was doing. Lastly, is my factory alternator going to handle this much power or will I need a new one with higher amperage output? I also bought a Rockford Fosgate 1/0 AWG amp power kit that included 17ft of power cable and the ANL fuse holder w/ 300 amp fuse. Is that kit only enough to do 1 amp or will that be enough for the entire car? Is that wiring too big or will it be ok? Any help with this would be greatly appreciated...like I said, when it comes to car audio, I'm out in left field. I just don't wanna get taken advantage of when I go to have all this installed b/c its like another language for me and I'd like to have everything I need for installation and just pay someone to hook everything up. Thanks a million and try to take it easy on the idiot new guy(ME)!//content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

In all fairness. That was extremely wordy, and hard to read compared to most posts on this forum.

The short answer is this:

Think of the subs by the airspace they occupy. (2 subs in the same box with no divider inside are using the same airspace.)

Obviously, when a sub hits, it creates air pressure inside the box.

Now If you have 1 amp powering 2 subs, It's generally acceptable to let them share the same airspace. This is because the subs HAVE to be playing the exact same frequency, and thus when they hit, they both hit at exactly the same time and with the same exact signal, meaning the pressure caused by the subs hitting would counter-balance between the subs.

(In layman's terms: If both subs push at the same time with the same force, neither over power the other. But if one has a slightly different force, One will overpower the other.)

This can cause a sub which is at its maximum excursion (or distance from the resting position) to exert farther due to being pushed by the air pressure of the other sub(s.)

For this reason, 2 separate amps powering speakers that share the same airspace is not ideal. It might not seem like it, but 2 different amps will NEVER produce the EXACT same signal. The difference isn't likely going to be enough to hear, but a sub cycling at 40+ times per second feels even slight differences very very much.

So if your sub is playing a reasonably common tone (say 40 hz) and the signal between the subs is 1/80th of a second off, Your subs are playing opposite polarity which basically means one of your subs will blow easily with half of the power it can handle in a proper enclosure.

To simplify all this. here are examples of multiple sub setups:

Same airspace, 1 Amp = //content.invisioncic.com/y282845/emoticons/thumbsup.gif.3287b36ca96645a13a43aff531f37f02.gif

separated airspace, 1 amp = //content.invisioncic.com/y282845/emoticons/thumbsup.gif.3287b36ca96645a13a43aff531f37f02.gif (but not necessary)

Same airspace, Multiple Amps = //content.invisioncic.com/y282845/emoticons/thumbsdown.gif.d22f25895e9b40f2300c953691dacfa2.gif

Separated airspace, Multiple Amps = //content.invisioncic.com/y282845/emoticons/thumbsup.gif.3287b36ca96645a13a43aff531f37f02.gif

 

[cotjones 10+ year member]

For your second question. Capacitors do have a purpose. Most people on this forum will tell you otherwise. But reguardless, they do help.

That said. The difference they make is so minute you being at best an amateur car audio enthusiast, will NEVER notice any difference besides fooling yourself into thinking you didn't just waste 80 bucks on a cool looking tube just cause it says its necessary.

Most amps have sufficient quick discharge capacitors in them. They don't help much with deep discharges, but then again neither do after-market capacitors. If your electrical system can't support your Amp's current draw, it is actually likely that a capacitor will actually add draw to the system rather than help.

On the other hand, Extra Battery power does what most people want from capacitors but don't get. As does a bigger Alternator. The thing is, your alt and batt. work together. If you have a massive Alt but not enough Batt. to store any power, your subs will quickly discharge the batteries and amps if the draw is high enough.

I find most of the time, if you have a minor voltage drop problem a stronger (or additional) Battery helps a lot.

If the problem is a bit more major, you might need a bigger Alt and additional Batts.