Strange issue with 10" sub in coupe trunk.

[Fett]

I have 1 10" sub in a sealed box that hits harder and cleaner with the trunk open.

It is a Kenwood KFC-W2510 in a sealed .8 ft box, running off of a Sony mono 800 amp. I have it under the rear shelf in the trunk of my coupe. It is an angled box that sits perfectly between the front of the rear shelf (where the rear seat tabs) and the trunk hinge cross bars. The angled front sits just about in front of the back of the rear seat.

I was playing around with the settings on the amp, trying to get it to sound how I want. I listen to mostly rock/metal, and just wanted the bass to hit hard and clean. I am not trying to rattle my windows, I just want to feel the crisp bass.

While reaching in the trunk to change settings, then jumping IN the car to hear how it sounds, I noticed that with the trunk open, the sub hits harder and cleaner inside the car. I would jump in and it would sound perfect, then I would close the trunk and get back into the car, and the bass wouldn't be as loud or hit as hard. This is all from inside the car. When I finally got the bass to hit how I wanted, it would bottom out because I had the gain too high, and it would be too deep....kind of blending ALL the deep notes together.

What would be the normal course of action in a case like this? I was thinking of hollowing out the back of the rear seat some, it is never used anyway.

Thank you.

 

[68torinogt]

i have i kicker in a truck box from crutchfield and a alpine mono amp that is suposed to pull 2 alpine subs and i have the same problem but to my advantacge i can change my settings from inside the car i dont have to open the trunk but i dont like using all of my amp it gets hot.

 

[Fett]

Yea, I don't have sub out controls on my head unit. I have the eq....which I don't know how to set anyway, so I use Xplod....and treble/bass settings. I too don't want to overload my amp, nor do I want to blow or distory my sub, which is why I keep tweaking the amp settings.

I just wish I could get it to sound the way it does with the trunk open....when the trunk is closed. It would look akward driving down the street with my open trunk bouncing with the beat....all though it would sound good.

 

[68torinogt]

i havent had the car but a couple of weeks but i just havent had the time to mess with all of the stereo yet and i was waiting on the rest of my speakers but i have to have new tires and inner tierods and rack first so i can continue to drive it

 

[sunil6784]

With the trunk open, the whole car acts as a open-air box, with the sound going out the back. When you close the trunk, the sound is bouncing all around in the car, which muddy's the sound. SOunds like you've just gotta play with the settings more.

Also, those sony amps aren't *known* for their quality. I had the 720 version and blew it up running 2 tens. I then went to an MTX and the subs sounded a LOT better, w/ better tuning abilities.

 

[sunil6784]

http://www.crutchfieldadvisor.com/ISEO-rgbtcspd/learningcenter/car/amplifiers_faq.html#24

 

[sunil6784]

Check that link out, thats how to safely tune your amp. If you do that, and the sound isn't what you hoped for, then you may have to upgrade to a better combo.

 

[olymaster]

what you need is a custom down firing box for that trunk! port your trunk into car

 

[5.0 con-vert]

Either what the master said, or get a ported box or a bandpass unit. Some subs are made for sealed enclosures and some are much better in a ported environment.

 

[68torinogt]

my kicker was designed in a box for tight spaces i didnt buy the box and the sub separate

 

[Fett]

I am thinking of getting two 4" port tubes, cutting holes in the top shelf just to the inside of each deck speaker and dropping the port tubes in them. It should be clean looking and allow enough air in the trunk to solve my problem.

 

[Notched90]

I would get away from the sony amps, they are called "Xplodes" for a reason, and I have seldom heard good feedback about them. I had a 800watt amp running a 1030watt 10" infinity in my '90 notch for a week before the amp blew up from my re-attaching the ground wire w/ out disconnecting the fuse...sucks....but as for your box selecting, a sealed .8 cu. ft. w/ a 10" sub is a good choice for metal (my choice also).

To clean up your sound, I would make sure you have your amp set on the low-pass filter, and make sure your db is somewhere in the middle and your Hz aren't turned up too high as this will make your sub try to produce higher frequency sounds than it can, and make it sound muddy. Also, if you have a bass-boost option, don't crank that up too much, seeing as the speedier bass rythem in your choice of music will cause it to blur together. As for your placement, these notchbacks offer a PERFECT sub area with a box like yours or mine, so just make sure its slid all the way to the front, and angle it towards your interior, and if it still sounds sloppy, just experiment with the placement of the box.