Effects of a false panel

[Digitalwave]

So I finished my box up and before finalizing the trunk layout, I decided to test it out. I aimed it forward at first, and then I switched it and aimed it back towards the trunk. There was a notice difference with it aimed backwards, so I am going to aim it that way but I am worried about the effects of putting a false panel around the sub. Basically, the sub would fire rearwards and the false panel would have a round cutout so the sub would stick through it.

The wood is very thin, less than a 1/4" I'd say, and flexible. It's like a particle board that entertainment centers are made out of, just super super thin. If I put that panel in, covered in some carpet from Home Depot, is it going to have any effect on the sound of the system? Am I going to basically be blocking the bass in the trunk between the false panel and the back of the trunk?

[StereoInstaller1]

Nope, no effect at all. Build that wall, it will sound the same.

Right here is the classic debate...if you aren't gonna force ALL of the output of the box into the car, and I mean TOTALLY sealed into the cabin of the car, face it backwards. You will get "corner loading" on the bass, gaining as much as 6 to 8db.

The "longer wave" theory is wrong, complete bullshit.

The only drawbacks are more rattles and muddier bass. Your boxes output is now 180 degreess out of phase with your main speakers, no biggie. Just to see which way sounds better, try reversing the wires going into the box...rig wires up so you can do it while sitting in the drivers seat, with the car closed. You will hear a difference only where the main speakers cover the same frequencies as the sub.

The bass will be muddier simply because it is not in the same airspace as you, the listener. It must now bounce around the trunk before it gets to you, causing "time smear", meaning it is taking longer to reach your ears...on a small car like an E30, no biggie.

Are you happy with the sound? Didja go D3 or D6? When do we see some pics?

Glad to hear you have some progress going on.

Luke

Build your false panel (pretty panel) and make it pretty.

Personally, I build the panel first, then the box. After I am sure where the box fits into the panel I cut my woofer hole in the panel, THEN I cut the woofer hole in the box. Sounds like it may be a bit late for that advice though.

BTW, most any stereo shop will sell you the much thinner trunk liner material. Much easier to work with than the Home Depot stuff.

[StereoInstaller1]

OH...I forgot to mention...it takes me an hour or so to build the basics of a box. Angled face, all other sides vertical, like I did for Jordan. From there, making the box seal into the car completely usually takes 2 or 3 hours more.

In other words, the hard part is the seal. Even on an easy car like the E30.Try this shit on a '82 caprice sometimes...fuck! Takes me 10 to 12 hours to get it done, even with as long as I have been doing this....

Luke

[Digitalwave]

What do you mean by seal into the cabin? I am running a sealed box, do you mean when you make ported boxes like Jordans?

It sounds quite good. I have a little bit of tweeking to do on the amp, but so far its seems like it is just what I wanted. It complements my system, doesn't overpower it. The soundstage is great too. The components really shine without the 5x7's holding it back now.

Thanks for your help Luke! I chose the D3 by the way. I am impressed with it's design. I also haven't wired my capacitor up yet. I am going to look at audio stores for carpet but to my knowledge none around here carry carpet. The Home Depot stuff is pretty thick but it works.

[fretburnr]

I am going to look at audio stores for carpet but to my knowledge none around here carry carpet. The Home Depot stuff is pretty thick but it works.

i used some home depot stuff in an IS300 last year and it worked out great, i wouldnt hesitate to do it again

[StereoInstaller1]

Fretburnr, since I have been doing this as a pro since 1980, I am kinda spoiled in my choice of materials. You are right though, HD carpet works, but take my word on this... it is much harder to work with. Especailly if you are doing a panel that has contours in more than 2 directions. If you got hold of the stuff I normally use, you would agree.

If you tried to upholster the panel that covers my battery and is the pretty panel for my MD and CD changers you would REALLY understand!

Spray glue adheres better to trunk liner material too.

As far as the box seal....cut a panel of 1/2" MDF the same width as the area between the vertical ribs surrounding the ski boot hole in the trunk. Now cut a hole for the woofer (big enough to allow the woofer to come through completely), then screw that panel in place in the trunk. Apply weatherstripping to complete the seal. Now build your box, with the proper angle on the front. Next, push the box against the panel so you can precisely mark the hole that the woofer comes through...THEN cut the woofer mounting hole in the box...take apart and mount the woof.

Jordan simply ran a port through the rear deck. Well, maybe not simply, but you got the point. The work of sealing was done properly, both woofer and port were completely sealed into the cabin.

See what I mean when I say this part is a PITA? This is part of why my systems are known for incredible clarity. When I get my car to the shop I will take more pics how I do this.

[Digitalwave]

Luke, what do you recommend for cutting the carpet around the cutout in the false panel that the sub will poke through? How do you evenly cut the carpet so I can fold it over the end of the wood, so you don't see any of the wood?

[StereoInstaller1]

uh...wrap and glue? I just bend the carpet back and glue it on the backside of the panel.

LF

[sweetride01]

This is great DJ you are saving me so much time and trouble by asking all the questions for me...
We'll have a sound-off at a car meet sometime.

[Digitalwave]

This is great DJ you are saving me so much time and trouble by asking all the questions for me...
We'll have a sound-off at a car meet sometime.

It's T.J. ;) What setup are you going with? I am happy with mine, its tight, definately not too loud though. You can't hear much at all outside the car.

[fretburnr]

no i totally agree, the pro stuff is "like buttah" compared to the home depot carpet... but the hd stuff for an amateur/home job certainly looks the part and is pretty durable

[sweetride01]

It's T.J. ;) What setup are you going with? I am happy with mine, its tight, definately not too loud though. You can't hear much at all outside the car.

My bad... I'm DJ. :rofl:
eDi6500 components, and a SoundSplinter 10" sub... though I have yet to get it, cuz it's on backorder.
I hope to have everything done be early-mid January.
I'm still not sure where to start with my kick panels though.

[808BMW]

My bad... I'm DJ. :rofl:
eDi6500 components, and a SoundSplinter 10" sub... though I have yet to get it, cuz it's on backorder.
I hope to have everything done be early-mid January.
I'm still not sure where to start with my kick panels though.

what's on backorder, rl-i's?

[sweetride01]

what's on backorder, rl-i's?

Yup... the guy had to get some baskets made in China, and he's still waiting for them.

[ak96ss]

As far as the box seal....cut a panel of 1/2" MDF the same width as the area between the vertical ribs surrounding the ski boot hole in the trunk. Now cut a hole for the woofer (big enough to allow the woofer to come through completely), then screw that panel in place in the trunk. Apply weatherstripping to complete the seal. Now build your box, with the proper angle on the front. Next, push the box against the panel so you can precisely mark the hole that the woofer comes through...THEN cut the woofer mounting hole in the box...take apart and mount the woof.

Jordan simply ran a port through the rear deck. Well, maybe not simply, but you got the point. The work of sealing was done properly, both woofer and port were completely sealed into the cabin.

See what I mean when I say this part is a PITA? This is part of why my systems are known for incredible clarity. When I get my car to the shop I will take more pics how I do this.

I'd like to see those pics... As soon as I get the transmission back in, the timing chain replaced, and the front suspension redone, I am moving on to the stereo, and I'll need to build a box for the sub.

Once I get to that stage, I'm sure I'll be back with questions, as this will be my first box since about 1987... :D