experienced box builders: help me!

[CdnCory]

I am building a box so that the sides fit in between my wheel wells. The ports will come out of the box so that the bottom clears the wheel well. My question is: will it slow down the air having a 90 degree bend coming out of the box? Should I angle the one corner? (kinda confusing so take a look at the pic)

 

[jeff96]

check out the port calculator and see what different results the numbers give you. Port calculator is at carstereo.com

 

[CdnCory]

I found a air speed calc. on that site, but not one that would help me for this application.

 

[sparkmechanic]

Air flow

For each 90 degree turn reduce air FLOW by 50%.

 

[CdnCory]

For each 90 degree turn reduce air FLOW by 50%.

Did you get that off of a website? If so, can you post the URL?

 

[davesexplorer]

unless you're going for all out spl and sq, you really shouldn't notice a difference provided the rest of the enclosure is up to specs..

 

[CdnCory]

You dont have a choice BUT to go all out when the box is for 4 12" GTi's

 

[superxplorer]

http://forum.sounddomain.com/forum/ultimatebb.cgi?ubb=get_topic;f=11;t=073815

just had to post that

 

[CdnCory]

Did you post that just to prove that I havent really gotten much help?

 

[superxplorer]

na i really posted it so i can recieve emails telling me about this thread because im trying to figure out how i can make a box that goes over the wheel wells also. i no making a sealed box would be easy but idk about ported. but instead of using a slot port would it be alot easier to use a 4 inch diameter pvc pipe?

 

[CdnCory]

I have heard that using PVC can give you 'whistling' noises in some setups. Also, this box (ideally) needs to be 9 cf. If I were to throw in a 4" round port, that would be taking away from the internal volume. This way, I make a box that fits in between the whell wells and the ports extrude from the box and I can maximize the cargo space. Here is a pic just incase you arent following

I dont really wanna go into too much detail about the design in this thread, I want it to stay on topic.

 

[superxplorer]

o wow thats nice. what kind of software is that and also dont you have any worries about pointing the subs facing up since things could get thrown on top of them. and to answer your question up top u should put that 90 degree angle in the corners it will help move the air fast.

 

[CdnCory]

o wow thats nice. what kind of software is that and also dont you have any worries about pointing the subs facing up since things could get thrown on top of them. and to answer your question up top u should put that 90 degree angle in the corners it will help move the air fast.

I did that up on rhino 3D one night. Two of the subs (the ones closest to the seats) will be inverted so that I can get a bit more volume outta the box. As for the other two... I'm not worried about things getting thrown on top. This box is going to be level with my back windows: I will have no cargo space left over, so I will wont be 'throwing' anything back there.

 

[superxplorer]

also isnt it better to face the ports toward the back of the hatch rather then up to the ceiling.

 

[CdnCory]

The ports should be on the same plane as the subs

 

[davesexplorer]

not really, generally it is a good idea but sometimes it works better to have the subs in a different configuration than the ports....

a "crx box" is a good example -- in some vehicles it tickles the meter in just the right way...

Is each sub going to have its own chamber and port?

 

[mexi]

he is right thats what i run
http://www.cardomain.com/memberpage/703997
and if you use those kind of ports you will not get whistleing from them.
they actually work better in some applications than slot ports

 

[expo5.0]

in my experience firing up in the explorer is what tickles the meter the right way.

I've built about 12 boxes for explorers at this point (and 5 or 6 of them were remakes of boxes with the same subs trying ot get a little more out of them) I've found unanimously so far that firing up is the loudest and rattles the least.

 

[CdnCory]

like I said, i didnt really want to go into too much detail about design. Thats great if you have round ports, and thats also great if your ports face back. This box is not designed to be a crx box, it is just a plan jane ported box in which the ports on the same plane as the sub. I have never looked into a crx box but I imagine there is some theory behind it, and not just a box with the ports facing backwards. There are applications for every kinda of box and there are alot of times where they sounds like s**t. Just because you have round ports doesnt mean that they dont whistle. If EVERY round port made a whistleing noise there would be no such thing as those stupid prefab boxes right? "I have heard that using PVC can give you 'whistling' noises in some setups". key words: SOME SETUPS.

expo5.0: I appreciate the post, its nice to have some input thats been actually proven for this application

 

[mexi]

well the whistleing you refer to is called vent mach and is a result of the port being to small. you can make a slot port make noise if its to small.