shizzzon

with steel, i would glue them, sealant around the edges to make it smoother, then run bolts through the steel to keep the steel pressed up against the wall as tight as possible.

ok, the following pics are pics of extreme bracing. You can opt to use all bracing shown but the following pics are mainly geared to show you or help you develop your own bracing ideas... or you can do this, it's fine. If you opt to do your own bracing style, do your best to prevent air flow restriction and prevent yourself from obstructing the port exit. The following pic shows how the port walls wil be braced. The red is allthread and the brown is 2x4s. Notice how there is a 2x4 at the bottom floor to prevent it from flexing. When installing the top on, you may want to run 2x4 across the top of it on each side from front to back. If they wont fit on the outside, run them on the inside. Expanding foam wont be a brace so don't expect it to help if you use foam. This next pic is a pic of the whole build braced- In the back of the wall, there is a steel bar back there. You will probably want to use more than that in the design. The purpose is simple- all-thread is great at keeping things square but does not offer great dispersing strength around where it comes out at. So, you need to "connect the dots" so you can brace more surface area from point to point. the runs running from side to side of the wall, connect all those together with steel, for example, and so on. Again, you dont have to do all of this but low notes will flex the hell out of a box and i like to overkill bracing like i overkill everything else...

i didnt want you to run 3kw+ facing everything to the rear unless you had massive amount of free space around the trunk for the box to breathe. You must also realize that you will need a TON of deadening back in that trunk if u faced it like that too. Expect your trunk latch to fail, brake lights possibly, loose wiring... anything that is fragile back there. Firing forward is a better scenario for you. Plus with that kind of power, you will have a great port area design firing forward. For the music you listen too, i think u are goin overkill on the subs unless, like you say, u want competition too. 2 12s and 3kw+ is gonna kill your front stage. Back when i ran 2 12s and 4400w, i always had to attenuate the bass for the music to sound well balanced and my front stage is ran off of a 100.4

if i put the right port in there with door open, 153.1 at the head and 156.0 in the kick. with music, i custom tune a lot of songs to my peak so i bet i can pull a 152.5 easy with custom tunes for bassrace, etc... i like your extended out wall bend! give me new idea to play with in CAD.

I hope there are a lot of wall or has-been wall users out there that can contribute to this thread. I'd like to see some suggestions for wall users on increasing their spl potential. I am about to seal my wall up soon so after i do, won't be too much more moddin possible in that area of the car. I'm lookin for 155s hopefully. I'm wanting to stay in Modified 3 in MECA and i am assuming they'll qualify me for that class... I have a scion tc with a wall behind the b pillar about 5 inches back. I will be using 1 60A fuse for each of my 2 3500ds. I am wide open to suggestions to get louder.... I have yet to meter myself the MECA way but in the driver kick i did 151.7 clip-free and a 152.19 clipped heavily. amps pullin around 130A per amp so that might be low enough not to pop a 60A fuse but who knows. i am about to seal the wall with lots and lots of expanding foam. I will find my new peak frequency then build multiple test ports til i get loud. I will try smaller port area after i find my peak to see if it helps as well. I may try to slightly angle the port toward or away the mic to see if that helps since i am a few inches behind the B pillar. I was thinkin about filling my rear floorboards with mass but i dont think i am allowed to per the rules.... I dont know really what else to do... MY sunroof leaks air, i can try sealin it up more but besides that.. i dont know anything else to try.

even if it does help, we are talkin minute gains.i'm currently tryin to find 2 more dbs out of my install...let me know anyway your results.gains always cost money

ok, i'm gonna be completely dumbfounded and noobish but what's the point and how does it benefit for walls? I could see time delay working if the subs were out of phase or having cancelation issues unless u are saying walls have it somehow...

i forgot to add that even though the port is tuned crazy low, it still peaks loudest at 50hz.

hehe, let me get u a drawing sometime later on so u can see what i'm talkin about. My port was tested starting at 25.5" and cut 1" off and test until i reached 16" long. At 20" long, the output was greatest at the driver side headrest. supposedly, at 20" long, the wall is tuned to the low 30s like 31-34hz. The more i shrunk the length, the worse the score got. If my port area increases, so will the length and i wil physically have to make a LARGE tunnel in the wall which may actually cause some subs not to fit on the baffle! I'm pressed for space.

i dont know the strength properties of going with mdf light or virtually any other wood that is lighter AND costs nearly the same... Typically, the lighter the wood is, the more expensive it will be if retaining or even increasing it's strength. Some wood used in boats cost over $200 a sheet and is very light but impractical. My suggestion is to use bracing in the box just as a precaution for whatever lightweight material you choose to use.

the wall has been built for a while now... If the port was on the far side, it could only go back 14 inches... now, even if i didnt need that depth( my best port length right now is 20" so i would need it), the port area wouldnt be as big because my car contours differently than older imports so i can't stack 15s on top of each other.. It's like this- ...0..PORT..0 ......0......0... The port area in either corner would be crazy low. My port i use now is crazy low area, lol, but at least the most i could get out of the design. I'm always designing new things for my car and saving them as backup projects. My current port area is only like ~145sqin... very low for 4 15s. My latest project design i did for my car was 6 12s, 18,000w and 316sqin of port. Concrete design as well.

look at steve meade's escalade he did for somebody with 8 18s. It's the same design. You can keep shouting out ideas but i'm pretty sure i've tried everything out there that i could possibly think of. The other design which almost worked was a diamond in the middle with all 4 21 facing each other inside with a port on top, bottom, left and right... Problem with that design is it gave off only 490sqin of port area and was far more complex to build and just wasn't worth it.

i use CAD software to design my boxes, trust me, the port can ONLY be in the middle. The baffle is 52" wide x 26.75" tall but the middle of the baffle stretching 15.5" in each direction allows a 1" height clearance. The wall only goes back 14" before it's drastically shrunk to 36" wide throughout the rest of the design. Therefore, port must be in an area that doesn't constantly maneuver around objects and has the most potential for port area.

the extra width wasnt necessary for this design

ok, here comes the specs!!! yay! lol. Internal Volume will vary based upon amount of bracing used! What i did was base design off of approx 35-36cuft cuft NET tuned to 30-31hz. I will give you the specs now, gimme a couple days to finish the design- These are external dimensions, please double layer ALL sides everywhere! including port baffle. 48" wide 45" high 33" deep Internal space for this section - 45" wide 42" high 30" deep Next, external dimensions behind this part of the chamber- 48" wide 40" high 19.5" deep Internal space for this section - 45" wide 37" high 19.5" deep Total external depth - 52.5" Total internal depth - 49.5" Port specs - Port Area - 42" high x 14.5" wide = 609 sqin Port mounted behind double baffle of front of box, port wall depth - 30" This is the same wall the subs will be mounted on. This port area is built directly down the middle of the front of the wall. Looking at the front of the wall - 16.75" of bare wood on the left, 16.75" of bare wood on the right of the port opening. This equals - 33.5" of solid frame on front. 14.5" is port opening = 48" total width as calculated. Expect design soon. This should be all the dimension info you need. Once design is posted, i will explain some more detailed areas so u wont get confused when u see them.

i still cant create anything else except for that so i'll go with it.

lol, now we are talkin, u just got offered help throughout the whole week. You about to start Car Audio 301 - The Wall in the parking lot...

haha.. that's awesome

so.. did his radio stations work, lol

I'll make sure u get it done this weekend! You said - I still need to see my family, girlfriend, and cut thelawn (takes 3 hours to do because I make that shit look like a golfcourse). This only leaves me with saturday morning from 8 to 12. Thenpossibly some time sunday afternoons So, tomorrow, i'm gonna come up there, eat dinner with your family, take your girlfriend to cedar point the rest of the week, cut your grass with an exacto blade for utmost precision and make a replica of edward scissorhands and then go to lowes and buy you some more glue... By this time, you should definitely be done,

Yep, our state hes held quite a few records in MECA over the past several years. That install that was done out of marble burped over a 156 with a single sub. That's still yet to be beaten in this state. 2 other competitors, friends of mine, just took state and hopefully world record coming up with the loudest Amateur Street division vehicle out there.. State record was awarded to one of them for being able to burp a 147.3 on music with the vehicle OFF using a single battery and 1 15 non walled off of a 20A fuse! We've been doin some pretty good scores here recently. I can go on about others but we've got a lot of knowledge people in this area. The marble design was interesting to say the least. Of course it wasn't meant for a daily setup as was stated earlier but was definitely an interesting build.. Took every bit if that material to get that record and still holds it here.

nobody can sell Fi because they are made to order

no, my peak remained the same, it just slightly increased pressure right around tuning frequency.

there's a reason for that, lol. I'll spill the beans- I stuffed 5 cubes of acoustastuff in my wall, spread out and tested the frequency range. Wall tuned around 30hz, peaks at 50hz due to car's peak note. I did not see an increase in pressure reading until i started metering in the low 30hz range! So, almost 20hz below peak is when it started to increase pressure... The increase in pressure is greater if the port is tuned to peak at where the polyfill was working in anyways... so it was kinda useless. i would only recommend it in a daily build.

I don't even know why i'm posting this but i'll post it anyway- I always tend to research alternatives to the equipment i'm using to see if there's something better that i could be running and i did a design which would rival what i got now... Am i switching? NO. I will continue to better the design i have now until nothing else works... At that point.. I MAY go to this new design- I have a design i got saved for myself which consists fo the following- Below is a comparison to what i have now vs the new design- Now - 4 15s = 3,164 SD area @ 7kw. Port area = 145sqin (terrible) New Design- 6 12s = 2,964 SD area @ 18kw. Port area = 316sqin Lot better! The design may include the use of concrete as well and would be attempted to set a new world record in ModEx divisions. Again, i'm not saying i'm gonna do this... but i do got the design saved just in case,