I am running an eclipse 5441 HU with a JL 300/4 to a set of MB quart premium components 6.5in (tweets in the my04 local) and another set of 5.25in behind the seats. I recently dropped a grand into 2 Wlaruent boxes and Pas2k's flat amp rack with another JL 300/4 for 2 8inch MBQuart reference subs. The cabin sounds great. But my trunk has 1000$ worth of weight in it. I have the amp tuned properly with a sine wave cd and I know the WLaruent boxes are .38cu and subs need .5 so i packed them full of polyfill to offset that and if I AM REALLY LUCKY you can kinda hear some bass at a dead stop and you listen really hard. At speed or with the top down? FORGET IT you can't hear anything. The subs don't hit at all unless you put your head in the trunk between them. This is not my first time around the block and I am lost. The amp will push 150x2 bridged at 3-8 ohms and my subs are dual VC at 4 ohms per coil. Wired parallel makes 2 ohms per sub so that won't work. In series they make 8ohms per sub. AHH perfect. NO. I thought about a phasing problem but removing 1 doesn't help the other. I thought it was lack of air transfer but I am not the only guy using W's boxes and Pas2k's rack so I would have heard of that problem already. I am about to take the SH** to the flea market and get a JL stealth box and a 10W7 throw about 500 watts to it and let her rip. I would not like everyone in the neighborhood to hear me coming but I WOULD like to hear it.

Somebody help me. All I ever hear about is how much people love the sound of the eights in their trunk and I would really like to be one of those people but I am not on the right track at this point.

 

However, this isnt to say you cant have an 8" sound great. With proper enclosures, they are INCREDIBLY clean and crisp. In an s2000, 2 good 8" subs is MORE than enough to rattle the paint off.


My two 8"s in my S2000 get pretty close to my old JL 12" subs in my last car.


just a couple of quotes to express what I am looking for.

sigh.

alex

 

how full are we talking about?

if they're stuffed like a pillow or even mildly dense, it's too much. it should be roughly a few handfuls loosely inserted at best. your goal is to slow air movement, not kill it.

are you 100% sure the subs are electronically in phase with each other?

you should be able to wire the voice coils in series for 8 ohm total, and then wire them in parallel for a 4 ohm load total @ the amp (which is right in the 300/4's optimal range)

what head unit do you have?

how are your gains set?

what crossover points?

finally -- what kind of excursion are you seeing from the subs? hold a ruler up to the side of the sub if necessary and estimate.

 

if i do that then there is only 1 channel driving both speakers right? i want to use both sets of channels. one for each speaker so that each speaker will have 150 watts. my reason in buying a 4 channel amp since i have 4 voice coils.


i think.

alex


this is how it is currently wired.

 

I know there is not to much poly becuase the sucked before I did that i was hoping it would help but really had no effect.

The Xover is set to 75Hz for each speaker. and the gains are adjusted to 34.6v dc which is what the manual said was 150watts bridged at 8ohms. any higher and there is distortion.

excursion is about .5 to .75 inches again any more and there is distortion.

the head unit is an eclipse 5441 5v front rear and nonfader preouts.

 

and I am 99% sure there are in phase becuase all the + are connected to +s and all the - are connected to -s and all the red wires are connected to red holes and so on. i have double check all this. but i am not 100% sure nor do i know how to be 100% sure they are in phase except check wires.

 

Your wiring looks good, the xover setting are reasonable. Looks like you've done it all right. I can only suggest to check for any leaks (between sub and box contact) and make sure the amp's input mode is set to 4-channel (would be pretty obvious if it weren't).

Maybe you need better subs & a juicier amp?

 

Determining phase is pretty easy, here is the quick test - put some music on and lightly touch each of the surrounds. If they are in phase they will both extend outwards at the same time.

Next - Make sure you are using the sub output from the HU, and are running it into both the Front and Rear Rt and Lt inputs on the amp (use a splitter). Then turn the filters off on the amp and use the sub filter from the HU. (I am not that familiar with the Eclipse HU product line).

Edit - Make sure you have 2 Chnl input mode selected and are using the Sub output from the HU into the Front RCA inputs.

Even though JL Audio states that you get equal power from 3-8 ohm with the RIPs circuitry - I have found that not always to be true. I run a JL 500/1 and a 300/2 and can tell the difference between a 2 ohm load on my 500/1 and 4 ohm load on it.

My setup is two Rockford 4 ohm 8" HE subs on the 500/1. I can make car alarms go off down the street with it cranked.

I do not think I would have done the 300/4 for your setup. I would have wired the subs in parallel (@ 2ohms) and used the 300/2. Or left them at 8 ohm loads and put them paralled to a 500/1

In any case you must have an install problem. Even if at 8 ohms you were loosing 10-20% worth of power, you should still have very good bass with 120Wrms going to each sub. Make sure you have a good ground on the amp, recheck all your wiring and the setup from your head unit and are using the sub output and not the rear or front channels.

Hope that helps



Recheck ev

 

if you bought a 4 channel amp for all 4 of your voice coils, you would need to wire each voice coil to each channel on your amp. not bridge the amp. in your diagram, front and rear channels are bridged.

try this, use either front or rear outputs. in any 4 channel amp with one power supply, you will get a little less power than using just one output, either front or rear. so pick one, then wire your subs in parallel and from the subs, wire them in series into the amp. that will give you a 4 ohm load. see if there is a difference.

try wiring the voice coils individually to the amp first.

 

Try this....if you dont hear bass......

48% your amp is malfunctioning
48% your subs are malfunctioning
1% the bass/sub setting is set to low on the headunit (easy to overlook)
1% too much polyfill
1% bad wires (RCAs or speaker)
.5% enclosures are leaking (highly unlikely)
.5% Audiogods dont like you.