PORT HELP!

[bngblzr 0]

OK. Im building a box for my S-10 blazer and i need help with the port. The box is 38" wide 19" high and 14.5" Deep. It hold 4 RE SR 10 D4's. Id like the port to be now wider than 10" no taller than 6". id like it to be alot wider than taller just to kinda "fit" better... Thanks in advance

-Mike

[Adrian_D 520]

For your subs you will need a certain port area. Find that and you can use almost any width / height combinations, with some common sense.

[bngblzr 0]

how do i calculate port area?

[ABXX49 20]

H(in) x W(in) of the port will give you your port area in square inches

[bngblzr 0]

ok. but how do i know how much the subs need for port area? can somebidy help me find it?

[lee 2]

Guessing your measurements are external, I get 6cubes gross to start. Are you using 3/4 material? And any double baffles anywhere, or bracing?

[bngblzr 0]

i have a 2x4 in the middle for bracing. 3/4 MDF is right. The subs want 1 cube a piece. so are you saying i only need 6 inches of port area? my buddy made one that looks way to small 7 LONG 1 HIGH 3 DEEP so 7x1x3 is that right looks tiny.

[lee 2]

NO, take your measurements again by subtracting 1.5'' from each angle. Dont know what port area will be till you know what net volume you have.

[B7L|BL4Z3R 4]

try putting your dimetinos into the re box calc and mess with the port ares untill you get the hertz you want

[bngblzr 0]

YEA me and LilTeddyP are building the box so were gonna change the port tommrow..

[lee 2]

Huh?

[Adrian_D 520]

I'd use half the surface of the subs for port area. So for 2 10's, use as much port area as the cone area of 1 10.

IMO it doesn't matter if the sub is in 0.5cf or in 20cf, it's still going to have the same excursion potential (diffrent power levels for the 2 examples) so it will need the same cone area to prevent port noise.

[bngblzr 0]

Huh?

It was suggested to use the box calc. until i get the right Hz.

[bngblzr 0]

I'd use half the surface of the subs for port area. So for 2 10's, use as much port area as the cone area of 1 10.

IMO it doesn't matter if the sub is in 0.5cf or in 20cf, it's still going to have the same excursion potential (diffrent power levels for the 2 examples) so it will need the same cone area to prevent port noise.

ok i guess well try that. thanks

[lee 2]

Huh?

It was suggested to use the box calc. until i get the right Hz.

I thought you were giving up for a second. So you and your boy are going to build this from a box calc then?

[bngblzr 0]

ok i called RE TECH today and he said 12.5 square inches PER cubic foot of internal space. well my box need 4 cubic feet so i need 50 square inches of port? he said the port has to be 20 inches long. THATS A BIG PORT FOR FOUR 10's. does that sound right?...

[bngblzr 0]

RE tech support said 12.5 square inches per cubic foot of internal volume. 20 inches long. That seems like a lot for tens. sound right?

[dbjunior 0]

its a good size its only 5x10 the length though depends on what you tune to.

[bngblzr 0]

ok well i want to be tuned to 32Hz so how long would that be? Im sorry im such a noob... i just dont get all this yet...

[BKOLFO4 29]

RE tech support said 12.5 square inches per cubic foot of internal volume. 20 inches long. That seems like a lot for tens. sound right?

That will work.

[bngblzr 0]

so being 20 inches long, will make me have to port out the side... is that gonna cause any problems?

Edited November 7, 2008 by bngblzr

[ABXX49 20]

Your port doesn't have to be 20 inches straight, it could be 10 deep and 10 to the side. An 'L' shaped port.

[lee 2]

so being 20 inches long, will make me have to port out the side... is that gonna cause any problems?

I was wondering why the port in your sig pic is so small. What is the H x W measurement on it anyway? Now I understand, after the comment about how big the port was for 4 10s.

[bngblzr 0]

the port for the 4 12's did look small but thats what the shop biult it to be. SOUNDED amazing. til some dickhead stole it....