throwing around ideas for a new box. gimme input.

[skittlesRgood]

1st some info. box will be about 24L x 45W x 11-15H (depending on if i stick with 12"s or go 15"s.) tuning will be around 34hz. subs are DC XLs. 3000w to each sub. its in an SUV. the goals here are... everything lol. light, strong, loud, sounds pretty good. it's not like I'm using SQ speakers here so it's not a big focus.

for my next box I want to do 1/2" birch or appleply with about 4 layers of fiberglass on the inside. it will still be double baffle so 1" there. do you think 4 layers of fiberglass will be enough? I have a plan to do one panel at a time before I assemble the box so I can make each panel as strong as possible. might do one piece of althread top to bottom, through the back of the port and actually to the floor. itll be my ancor to the car.

currently I have subs up, port back with aero ports. new box will be sub and port up and have a slot port. I'm planing on using big round overs on the port to help it act like the flare on my aero ports... cut up 3" pvc is what I think I'll use.

what do you guys think?

[skittlesRgood]

oh, each panel will be sanded down to a wet sand/paintable surface.

[skittlesRgood]

hmm... not even the one person to tell me what a horrible idea i have? lol.

[skittlesRgood]

come on guys, just gimme input on how many layers of glass to use.

[JaM Customs aka mprete]

well first off, why would you use birch or the other one if your going to be painting the box anyway? why not just go with 3/4 mdf and be done with it. but also, 4 layers is a lot and will hold up fine, if you didnt use any fiberglass it would most likely hold up fine. good luck

[IH8PunkRok]

i like the fiberglass idea. except for one thing. fiberglass is inherently brittle. so when you go to put the subs in you could crack the fiberglass losing some strength

a good way to combat this is to pre-drill all holes that will be needed (sub cut out, port cut out, threaded rod and screw holes) then fiberglass up to them. for the screw holes you can get a piece of plastic or metal rod to place in the screw holes that can be removed after the fiberglass cures. that way your fiberglass will be strong and not crack

that leads me to the next weakest point. if you fiberglass the panels unassembled that makes your bond joints your weak spot. consider glassing them after the box is together.

it sounds to me like you are way over building this box and that is great no flex = more dbs and you know that.

oh one last thing. the flared slot port since you are using pvc you have two good options for attaching it. a butt joint or a recessed inlay. i prefer the inlay. just rout out the thickness of the pvc into the port wall attach it with nails or screws and some strong glue then bondo or glass over top to keep it smooth

this sounds to me like a badass box. be sure to take tons of pictures

[Decaf]

id rather have 2 12s in a 3/4" birch/mdf proper box using proper proven building techiniques rather than guessing with fiberglass

u have plenty of room to do a short box for 2 12s in the trunk without restricting air flow as much as u would have with the 2 15s since they need another ~3cuft

[skittlesRgood]

well first off, why would you use birch or the other one if your going to be painting the box anyway? why not just go with 3/4 mdf and be done with it. but also, 4 layers is a lot and will hold up fine, if you didnt use any fiberglass it would most likely hold up fine. good luck

you think I'm just going to paint the box? you dont know my projects very well

i like the fiberglass idea. except for one thing. fiberglass is inherently brittle. so when you go to put the subs in you could crack the fiberglass losing some strength

a good way to combat this is to pre-drill all holes that will be needed (sub cut out, port cut out, threaded rod and screw holes) then fiberglass up to them. for the screw holes you can get a piece of plastic or metal rod to place in the screw holes that can be removed after the fiberglass cures. that way your fiberglass will be strong and not crack

that leads me to the next weakest point. if you fiberglass the panels unassembled that makes your bond joints your weak spot. consider glassing them after the box is together.

it sounds to me like you are way over building this box and that is great no flex = more dbs and you know that.

oh one last thing. the flared slot port since you are using pvc you have two good options for attaching it. a butt joint or a recessed inlay. i prefer the inlay. just rout out the thickness of the pvc into the port wall attach it with nails or screws and some strong glue then bondo or glass over top to keep it smooth

this sounds to me like a badass box. be sure to take tons of pictures

I will be glassing the edges once its all put together. either that or I'll leave enough of a lip to add wooden 45*s. I didn't think about how I would mount the PVC yet but I like the inlay idea. that helps a lot.

do you really think it'll crack when I hit it with the router? I'm going to use T-nuts, mount them and tape over the hole then glass over it. then I'll drill out the bottom of the hole. or at least that's the plan.

id rather have 2 12s in a 3/4" birch/mdf proper box using proper proven building techiniques rather than guessing with fiberglass

u have plenty of room to do a short box for 2 12s in the trunk without restricting air flow as much as u would have with the 2 15s since they need another ~3cuft

I completely understand what you are saying but I have reasons for all of it lol. I want to build it this way mostly because I want to do something that has never been done. If everyone else is doing it, I dont see the point because I already know it works. I guess I like to experiment.

I will most likely move to 15"s once I have the cash to toss around. this design was for the 15"s but since I probably wont get them for a while, I figured I would test the theory with my 12"s. I'll probably build it out of MDF first to make sure it doesnt fall on its face before I spend all the money on fiberglass.