Custom box not loud enough

[notorious97200]

The subsonic (or infrasonic) filter should be set at a frequency under the tuning of your enclosure, like 4 hz below for example.

If you don't know the ttuning frequency of your box, try to set the ssf around 30 hz, and the LPF at around 80-100 Hz.

[skittlesRgood]

post the box specs. all dimensions so we can tell you how much airspace you have and what you are tuned to. then we can tell you how to make it better. be sure to include the size of the port opening and length.

[darkesthour344]

here are the specs to the box. I built the ported box. since i have two subs i pretty much made two boxes side by side, and divided the two boxes by two 3/4" pieces of mdf. and to answere your question EL1t3Bass, all my money goes to driving my ass to work 5 days a week. so $100 in gas, my car insurance, phone bill, and all that good stuff. the rents dont pay for shit. (how it should be) lol

http://mobile.jlaudio.com/products_subs_enclusure.php?series_id=25

[dugee81]

I believe the Q setting on your JL amp let's you choose which frequency you want the bass boost to affect.

[darkesthour344]

yeah, i tried doing some research on all the settings for my amp and no one really knows. and it doesnt help that i dont have the manual that came with the amp either :/

[dwz]

I believe subsonic and infrasonic are the same thing. so in this case my Infrasonic filter is shut off. I was told by the guys at the local car audio shop to leave it alone. The Lp filter slope is at 12db right now. Im running a kenwood head unit. The Rca's are by monster cable. Since the amp is a 2 channel, i ran the subs in parallel. Then i got Y splitter for the rca's. And the ground is bolted to the bottom of my trunk panel. I cut a "x" out in the carpet and bolted the ground right down, away from the carpet. Also i was wondering if you guys were familiar with JL's amps and settings. The polarity (normal/reversed) Infrasonic filter, theres a setting called "Q", and the center frequency. Im not sure what those all are.

Just so you know I read the posts you made after this one ... And I understand it's your first system. But with my first system, if you're not careful, you're gonna damage equipment. On my first system (which is my present one), I damaged a pair of components from Alpine, TWO subs individually, and TWO amps... Oh and a headunit's RCA jacks.

Ok, so subsonic should be 20 or higher. There's NO NEED to have it any higher than 25hz anyways, honestly. It's bad for most subwoofers because the boxes are usually tuned much higher than that... especially prefabs.. when subwoofers play songs below their tuning frequency, it causes more exersion of the cone, and usually isn't very loud to the ear, so many newbies turn it up to compensate then BOOM... ripped spider (happened to me twice, only with prefabs too).... LPF, keep it at 80hz to 100hz. I keep it at 80hz because my subs are handling less bass notes and consequently are more accurate on the louder/lower notes, and more efficient (i blew one of the subs @ 100hz and I know it contributed to its mechnical failure... on top of clipping).

What kind of Y-Splitters are you using? when I upgraded from radio shack to kicker I noticed a huge difference.

Was the ground sanded, free of any paint? Is the surface area of the bolt great enough to cover much of the ground ring terminals?

How old is your headunit? I had an older headunit that was clipping a lot sooner (like at 50% volume) than it should have. This was due to age.. Ironically, it was a kenwood. Now I rock ALL alpine other than wiring.

Is the ground on your headunit good too? A bad ground on the headunit could also cause overheating, which means the sound going to your speakers and amp is distorted and thus causing clipping and voltage drop - compounding the *not loud enough* factor.

(this may not apply to you). but if you have a 4 channel amp /w a HPF on it, and your HPF is turned off on your headunit, your headunit can over heat sooner cause its still sending everything UNDER the HPF you set on your 4channel anyways, only to disappear when it hits the 4channel amp. So if ya keep your HPF @ the same level as your 4channel amp, your headunit will be more efficient cause it's not sending signals that are going nowhere. Maybe I'm crazy, but when I changed my HPFs to be the same on my headunit and 4channel, it was more crisp/clear. This paragraph will probably confuse the shit out of you unless you are familiar with HPF and 4 channels/

Edited June 30, 2010 by dwz

[skittlesRgood]

"Q" is the slope. its basically a parametric EQ

[bobo333]

no "Q" is how wide the peak is on either side of the bass boost frequency, if you set it to say boost 40hz with a high Q it will boost the frequencys arouns 40 aswell (maybe down to 35 and up to 45) with a lower Q it only boosts closer to the frequency (maybe 39 to 41)

also at DWZ if you set the HPF on you amp and headunit to the same frequency they will add together so if you have say a 12db slope on each the speaker will see a 24db slope (not sure on the exact numbers but something like this), most times if you set the HPF on your head unit either turn it off or turn it right down on the amp so the frequency you set on the head unit is actually what the speaker sees

to the OP, a bigger box could sound better/louder, but also a stronger box... how strong are your boxes? do any of the panels of the box flex even slightly? when i braced my old dual 12" box to stop it flexing a little it got wayyyy louder and sounded way cleaner

[AI James]

no "Q" is how wide the peak is on either side of the bass boost frequency, if you set it to say boost 40hz with a high Q it will boost the frequencys arouns 40 aswell (maybe down to 35 and up to 45) with a lower Q it only boosts closer to the frequency (maybe 39 to 41)

also at DWZ if you set the HPF on you amp and headunit to the same frequency they will add together so if you have say a 12db slope on each the speaker will see a 24db slope (not sure on the exact numbers but something like this), most times if you set the HPF on your head unit either turn it off or turn it right down on the amp so the frequency you set on the head unit is actually what the speaker sees

to the OP, a bigger box could sound better/louder, but also a stronger box... how strong are your boxes? do any of the panels of the box flex even slightly? when i braced my old dual 12" box to stop it flexing a little it got wayyyy louder and sounded way cleaner

wrong, lower q is wider says my kenwood deck

[skittlesRgood]

no "Q" is how wide the peak is on either side of the bass boost frequency, if you set it to say boost 40hz with a high Q it will boost the frequencys arouns 40 aswell (maybe down to 35 and up to 45) with a lower Q it only boosts closer to the frequency (maybe 39 to 41)

you just described what a parametric EQ does. a peak in the middle with a slope on either side. Q adjusts how wide that slope is. what i said wasnt wrong at all i just didnt go into great detail.