porting a 350z custom box.

Printed From: the12volt.com
Forum Name: Fiberglass, Fabrication, and Interiors
Forum Discription: Fiberglass Kick Panels, Subwoofer Enclosures, Plexiglas, Fabrics, Materials, Finishes, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=104551
Printed Date: May 05, 2024 at 6:47 PM

Topic: porting a 350z custom box.

Posted By: slick_9191
Subject: porting a 350z custom box.
Date Posted: May 07, 2008 at 4:33 PM

So I tried and tried learning the mathematics for tuning curves w/ freq. and hz, but I just cant get it down. So I know this stuff is second nature for you guys, I figured yall could work this out for me in your head in a few seconds. I basically want to port whichever box is best for my subs. I know I can keep it sealed, if I wanted to do this I wouldnt be posting right now. I would just want to know how to get the best sound porting this, whether circle port, rectangular, or what. Thanks.

Here are the specs for my subs (2 Alpine TypeR's) and for the two different enclosures:

Sub Specs ========================:
posted_image

Enclosure 1 ========================:
posted_image

Enclosure 2 ========================:
posted_image

I dont care what the port looks like, just what specifications to have them.

Replies:

Posted By: tubbs04
Date Posted: May 10, 2008 at 10:22 AM

You're not going to be able just to stick a port in that enclosure and make it sound worth a crap. not trying to rain on your parade, but the box just doesn't have enough air space to port it. If you need 1.3 cuft per sub and the box has a total of .88 cuft it's just not going to work. I would look into either building your own box, or using different subs.

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Posted By: slick_9191
Date Posted: May 11, 2008 at 2:50 PM

i agree, i guess i just get the bigger one and keep it sealed. Thanks for the reply man.

Posted By: bellsracer
Date Posted: May 12, 2008 at 11:27 AM

A tip to help with the sound to get best effect from the Type-Rs:

Get wood glue and coat the insides of the boxes with it. This will help seal the box better. The glue will soak slightly into the wood and shrink better sealing it. Each chamber is .7cf so you can be generous with the glue. To take up a bit more space and give a seemingly bigger boom to it, stuff about 3/4lb polyfil-stuffing (think cheap pillow stuffing) into each chamber. They'll eat up a little bit of the excess space and slow the waves down for a slightly boomier sound to the Type-Rs. This should get you roughly into the optimum airspace volume.

Ganbatte ne!

EDIT: I take it back... partially... You can port on this enclosure, but there is a good chance for port flaring. (Think wind noise) If you make a port made from a 2" ID pipe that is 8" long from inside of box to end of port in box (Total 8.75" long) you will be tuned at about 33-34 Hz for some strong bass. Do not use poly-fil in this case. The 2nd enclosure is just enough to get a port in there, but do not expect an SPL blaster. But it will give some harder hitting bass around 34Hz

Now then, what amp are you planning to use? I recommend a Class-D mono amp. Most people tend to use 2-channel amps because it's cheaper for the wattage, but nearly all become unstable and heat up (ie, bye-bye wattage) and in many cases, it voids warranty. Wire the subs in serial-parallel form to get a 2-ohm final load. I recommend the Kicker 08zx10001 amp for this or the Alpine MRP-M1000 (if you want to keep it all alpine) for this setup. Both will provide enough power to power-up all the coils at full RMS with wonderful slope control. Personally, I prefer Kicker, due to cleaner power control (from my experience) and high signal to noise ratio (95+db weighted)

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