califf123

I want to change my subwoofer setup from a sealed JL 13w7 to a ported 15 (possibly Digital Designs, REXXX, or Adire Brahma or Tumult). I do not care about saving space in the rear of the vehicle. This includes spare tire space. Does anyone know of someone up to the challenge of building an adequate enclosure for a ported 15? The sub will be powered by either a JL 1000/1 or, preferably, a Rockford Fosgate Power 650 Mosfet. I have been considering making this change for about 3 years now, but I can't find anyone willing to put forth the effort it takes to make the enclosure right. It is just easier for businesses to build sealed boxes because they take less time and effort, hence more production volume and money for them. A ported 15 in a Z will be a challenge because the enclosure volume will need to be within tighter bounds than the rather wide range allowed by sealed boxes. Calculations will have to be made to take into account speaker and port displacement. Finally, in order to squeeze out enough airspace, the box may need to be partially or fully fiberglassed.

vantage350z

iTrader: (9)

are you dissatisfied with the sound of the 13w7? i think it might be overkill wth a ported 15.. and you will lose SQ. i get bored of my setup sometimes too, but dont downgrade. seems like you have a good setup. have any pics?

350zspl

iTrader: (3)

nice

you can go about 31" wide x 20" deep , and on a gutted trunk about 15" height at the license plate and higher at the strut tower maybe 18" high

so it would be a wedge

you can rear fire

this will not yeild that much air space

you need a sub that does not need more than 2.5 to 3 cu ft



i am doing my trunk now

1 each 12 " team RF sub dvc 1.5 ohm 2000 rms 4000 peak

i got 4 T2 15 " power series subs but i am gonna do the 12" 1st

and i am not sure if i wanna use my T2 15's or a team RF


if your gonna do it may i ask why you wanna run 1000 watts or maybe less

i am pretty sure that the JL and older 650 RF mosfet are about 1000 watts on a good day

350zspl

iTrader: (3)

this was my 2 ported T2 15"'s in my impala box would be 1/2 the size , and this is a wedge design







and my caddy with 2 T2






these set ups are sharing 3000 watts on subs @ 2 ohms

keep in mind guys this is not SQ , and it is not beauty , SPL only , it is about hitting a number

so you guys probably won't be feeling this

califf123

I don't have any pictures of the current setup. I am going with about 1000 watts because I don't want to have to install an extra battery and/or aftermarket alternator. I have 2 one farad caps and stock alternator, that's it. I also have a Rockford Fosgate Power 1000 Mosfet, but the amp itself is so large I am not sure where to put it with such a large enclosure in the car. I am very limited if all I have to work with is 3 cubic feet. I guess I could port the 13w7. Maybe I'll just have to wait until I get another car that will hold 6 cubic feet for my Punch Pro 18! I have a bunch of good old stuff that I am not using, and I am itching to put it to use. There's just no room for any of it! I love the 350z in just about every way, but there is very little space for sub enclosures. I wish the strut bar could be removed.

BTW, I bet that TRF 12" moves some air!

350zspl

iTrader: (3)

were are you located

i have my trunk stripped

give me time look at mine and duplicaqte if you wish

if your in Fl i will be happy to build it at the shop

my box 26" L x 17" width x 13.5" height

ported 2.25 cu ft
45 hertz

there will be room for a stinger 1000

RF X2 17"x 13" x 3"
RF T20001bd 23" x 13" x 3 "

plus distribution blocks
plus crossovers

there is more room than you need for 1 12" or 1 15"

if the sub does not need that much air space 2-3 feet

i am doing 1 12" with 3000 watts @ .75 ohm

califf123

I am in Georgia. It sounds like you have a workable idea. I would like my box to be tuned a bit lower (32 to 38HZ range). I would sacrifice some SPL, but the sub would play lower and I would get the sound I am looking for. The Audiocontrol DQX's subsonic filter will eliminate frequencies below the port tuning frequency.

califf123

I think I found what I am looking for! A Cerwin Vega Stroker Pro 15 has the following specs for optimum performance:
3 cubic feet net box (after sub and port displacement), ported with two 4" diameter/ 14" long ports (which tunes to 36HZ)
I could run it off the JL 1000/1. Although that is a little underpowered, it should slam like crazy. With terminal cups installed, I could simply interchange the CV 15" with the JL 13w7 depending on my musical tastes of the day.
I think it can be done, and I think 350zspl's idea of a large rear-firing wedge is a good one. I believe the output would be astounding. I am going to try it!

350zspl

iTrader: (3)

might be able to gain a 1" or 2" in height to accept the 15" sub at the licence plate if the rear windsheild wiper is removed and grommeted , the motor removed ,and the plastic cover removed

the rear windsheild wiper will rattle anyway so this eliminates that

15 " for sub + 3/4" mdf on top + 3/4" mdf on bottom + space 1/2 " or 3/4 " on top and bottom of sub

you will need at least 17.5 to 18.5 inches in height at the plate so you may need to remove wiper and assembly or leave wiper and remove motor and inner cover to gain the extra space

this is why i am doing a 12" 1st attempt due the the 3" less height of the 15"


you need to get in stripped trunk , with hatch down , and measure height at the plate before buying the sub

let me know what height you get

you can sacrifice a bit of depth to gain a bit of height

Paul350Z

iTrader: (1)

Did you learn this in econ 101 or accoustics 101?

ETA: let me explain. If a manufacturer builds a better mouse trap - in this case a speaker box with a (likely variable) port then people will buy it. A port will cost about $3 worth of plastic in volume and add 1/10 man hour or less to the production ... small potatoes. A ported box doesn't have to be air tight so your shoddy businesses looking for less effort could just skip sealing the corners or edges.

Most listeners of music would rather have a more accurate sound and a controlled subwoofer than a sloppy and loose sounding speaker. Many hear are more concerned with sound levels than quality. For them a ported or even better, a band pass enclosure will produce louder SQL readings. Porting is best done to match the speaker element so if a manufacture is producing boxes with speakers they are free to port and play with the parameters to make adjustments. Most people are going to lack the time, taining, and equipment to do such work.

350zspl

iTrader: (3)

http://www.rockfordfosgate.com/rftec...sure_v2002.pdf

read this before you build good basic knowledge

can't hurt