First Real Box Build. Need help with port deign.

[phantom240 5,000+ posts]

Okay, so im designing a box to go into my 1991 nissan 240sx. Its hard to get that car loud. Its small, and my sealed box would beat the crap out of you, but it wasnt LOUD enough for my growing bass hunger. So i designed this box based on some rough guessing based on estimates of available space and my previous box. Here it is.

As you can tell, i need to fine tune a couple aspects, and i need to calculate port length, and im not sure how to do that. Could someone help me with this?

Click to read more...

 

[phantom240 5,000+ posts]

come on im at a stalemate here until i get a few more things finalized.

 

[Chevyaudio 5,000+ posts]

Im gathering from that picture that this will be a dual chamber box....right. also what is that 21-23" measurement? For a properly designed box you are going to need exact measurements and volumes for each chamber.

and I have no problem designing the box up in sketch-up for you. I just need exact measurements.

PM ME with your info....

like Subs being used, power, and If the box has to be dual chamber.

 

[phantom240 5,000+ posts]

okay, heres the skinny on the 21-23, im not final on how far forward my box can extend, and every inch frward increases total volume by approx .3 cubes IIRC from my classtime i spent with this. Um yeah dual chamber i chose cuz the center divider gives it structure... um the subs being used are 2005 model Memphis audio m-class 12" subs DVC, running a 8 ohms each, parellel at the amp making it 4 ohm load. The amp is an alpine MRV-1507 (beast) putting out RMS @ 14v, 900w (underrated) the m class subs are rated at 200wRMS and400w peak, which is very conservative, considering ive run this setup for a year in a slealed box. I need to take a tape measure to my car so i can see exactly how much space i have to work with and how that will affect myport firing drection and sub mounting locations. I would have liked to mount the subs inverted witht he port firing up. Um... yeah i gotta get some measurements.\\I plan on upgrading to some different subs though, possibly some type-r's or memphis m1's... or newer model m-class subs.