Truck Port Dimensions

[Louderisbetter150]

I Have a 2.7cbft Box (Net Volume) I have 3- 10" Pioneer Premier Champion Pro subs inside of it. It is a Common CHamber Box and I am willing to do 1 or 2 ports.

The Round Port Suggestion for the subwoofers are here (IM sure thats single Chamber suggestions)

0.9cbft 3 x 3.5 (inch)

1.2cbft 2 x 2.5 (inch)

0.6cbft 3 x 7 (inch)

But I have a common chamber because im building under a truck seat and it has alot of bumps and grooves.

There's the manual if that helps any. I need some suggestion on NET port size HxWxD thanks

http://www.pioneerelectronics.com/St...Manual1120.pdf

[spooney]

what tuning frequency are you going for? makes a huge difference as far as port length. your enclosure is currently 2.7 net after sub displacement correct? adding a port is going to shrink that even more. In my opinion your box is already on the extreme low end of the scale for a proper sized ported enclosure.i'd go sealed with that volume or only run two subs as two subs in the proper enclosure is going to sound better than three squeezed into the wrong one. If you are dead set on it though I need to know the tuning you are shooting for. Is it possible in any way to have all or some of the port external?

[spooney]

If you use two 3 inch diameter ports that are ten inches long you can acheive a tuning of approximately 35 hz which is a good all around tuning for car audio. You will only lose about .1 cubic feet of internal volume. I personally would not run three subs in that enclosure regardless of what pioneer recommends. Often times manufacturers come up with those volumes more as a marketing spec than what sounds good in the real world. It sounds good for them to say that their ten will work in a .6 cubic foot ported box but I don't imagine it sounds too great in that enclosure. Most tens like .6 to .8 cubic feet SEALED. I would only do two subs if I was running ported with that size enclosure and I would also use aero ports if the budget allows. Parts-Express.com:*Precision Port 3" Flared Port Tube Kit | sound ports PORT TUBES port tube port noise kits kit ar

[Louderisbetter150]

Originally Posted by spooney

what tuning frequency are you going for? makes a huge difference as far as port length. your enclosure is currently 2.7 net after sub displacement correct? adding a port is going to shrink that even more. In my opinion your box is already on the extreme low end of the scale for a proper sized ported enclosure.i'd go sealed with that volume or only run two subs as two subs in the proper enclosure is going to sound better than three squeezed into the wrong one. If you are dead set on it though I need to know the tuning you are shooting for. Is it possible in any way to have all or some of the port external?

Alright so I would need to buy 2 of these and extend both of them to 10 inches?I see it says kit so im going to guess there's extensions.

and yeah I cant run this 2.7cft enclosure sealed ive tried while waiting on the answer for this port. and the box is way too big. No kind of pressure like their playing in free air so ive just unhooked them. Before I had the 3 of them in about a 1.5 cbft (Net) box sealed and it sounded alot better with much better SPL. And trust me that box before was a Temp with plywood and screws. So i'd rather try your recommendation than go back to the Temp So fast. and thanks for this help

[head_unit]

3" ports are usually too small for 10" subs, unless the subs don't have much excursion-or you don't turn up it loud (yeah right). The ports will "jam up" and not be able to flow enough air. That's a common problem in car audio. Another common problem is the space around both ends of the port(s) must be clear to let the ports "breathe" else the ports won't work properly.
--> It's hard to make small vented boxes with high SPL
That's why a trend came about towards super-heavy-coned subs designed to go in small sealed boxes. The same trend came about in home to make ever more compact home subs.

If 2 subs sounded thin in that box sealed, then 3 would fatten the bass.

But we could be more helpful if you told us the exact model numbers, and the Thile-Small parameters if you have them.

[Louderisbetter150]

I have these 3 subwoofers in the 2.7cbft now and its thin. No SPL and VERY Boomy at the moment. And these subwoofers are recommended for Sealed I know that but I would like a Port being in a truck you can only get the full sound with windows down with sealed Enclosures. here's the Parameters

Thile-small Parameters:

Fs - 37.2

Qms - 15.49

Qes - 0.69

Qts - 0.66

Vas - 0.221 cuft / 6.247 liters

Rms - 4.510 (N.S/m)

Mms - 298.41 (g)

Cms - 6.14 x 10^-5

Diam - 7.9 (inch)

Sd - 48.6 ( sq.in) / 0.031 (sq.m)

Xmax - 11 (mm) / 0.43 (inch)

Hvc - 45 (mm) / 1.77 (inch)

Hag - .91 (inch) / 23 (mm)

[Louderisbetter150]

Re - 1.5

Le - 0.76

Zmax - 18.13

BL - 9.12

[Louderisbetter150]

Also I just downloaded and looked at WiniSD and the 2- 3" Dia port will allow me to only have to go 9.5"-10" length and the 2 4" Dia ports will have to be about 17" Length each..

But Im looking at the program now and What I'm seeing right now is with 2.6cbft Tuning the box at 50hz would give me a 10db gain at that freq? with 3" Diam x 3.7" length. is this right?? First time really using a program. Could this be because the sub is supposedly specially Made to be used in a sealed box so higher freq gives it better gains? Help me out here

[Louderisbetter150]

Nevermind I read a thread about tuning too high. And i looked at the difference between the Sealed and Port box. And i've gotta say the port looks promising.

[spooney]

do not tune your box at 50 hz unless you really dont like low bass. output is going to fall off rapidly below the tuning frequency and also the woofer will "unload" below tuning and act as if it is playing free air.I agree with what headunit said about 3 inch ports usually being too small but given your space constraints I suggested going smaller to leave you some enclosure volume. additionally aero ports are way more efficient than slot ports or even another round port that isn't flared at the end. one aero port kit comes with everything you should need(minus glue to hold the pieces together) to make a port up to 17 inches long. 2 - 4 inch ports would be better but at that point you're gonna start losing more of your already small enclosure volume.In addition the smaller the box is the longer the port has to be to keep the same tuning . Trying to get sufficent port area for those subs in a box that size is really going to be difficult.