Common chamber port size ??

[Roland 10+ year member]

I don't know squat about ported boxes. tuning, modeling.... I have 2 new subs that will be sharing the same box.

I was going to build the box based of the manufactures specs. They recommend 1.5 cubic foot box port are 3" dia by 7" long for each sub.

(I think this means it would be 38hz tuning but i cant find the calculator i figured that out on)

I am building common chamber box for both subs and would like to use only one tube port.

What size this single port needs to be?

It was suggested i make the box a little bigger than manufacture's recommendation but, ah,,, not sure how that would effect port size...

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[CSCStang]

I don't know squat about ported boxes. tuning, modeling.... I have 2 new subs that will be sharing the same box.
I was going to build the box based of the manufactures specs. They recommend 1.5 cubic foot box port are 3" dia by 7" long for each sub.

(I think this means it would be 38hz tuning but i cant find the calculator i figured that out on)

I am building common chamber box for both subs and would like to use only one tube port.

What size this single port needs to be?

It was suggested i make the box a little bigger than manufacture's recommendation but, ah,,, not sure how that would effect port size...

What are your dimensions for the box? And what tuning are you looking for?

 

[Jeffdachef 5,000+ posts]

I don't know squat about ported boxes. tuning, modeling.... I have 2 new subs that will be sharing the same box.
I was going to build the box based of the manufactures specs. They recommend 1.5 cubic foot box port are 3" dia by 7" long for each sub.

(I think this means it would be 38hz tuning but i cant find the calculator i figured that out on)

I am building common chamber box for both subs and would like to use only one tube port.

What size this single port needs to be?

It was suggested i make the box a little bigger than manufacture's recommendation but, ah,,, not sure how that would effect port size...

what subs...

and whats the dimensions you wanna give up?

 

[Roland 10+ year member]

The design right now has the box for both subs at 3.4 cubic feet. (0.4 cubic feet larger than recommend )

I don't know what to tune it at. I assume the manufacture's numbers added up to 38hz, so i should probably stick to that.

 

[Roland 10+ year member]

what subs...
and whats the dimensions you wanna give up?

Pioneer-TS-W1200PRO

Pioneer TS-W1200PRO PRO-Series 1500W 12" Subwoofer

 

[Roland 10+ year member]

My design is for the box to be 57" long, 14" tall, and say its 10" wide (the wide side is different angle but it averages 10") i want the port to be in the center bettween the 2 subs.

 

[Jeffdachef 5,000+ posts]

The design right now has the box for both subs at 3.4 cubic feet. (0.4 cubic feet larger than recommend )
I don't know what to tune it at. I assume the manufacture's numbers added up to 38hz, so i should probably stick to that.

need to know whats the max dimensions you are willing to give up. Tuning can be whatever it needs to be according to your own listening preferences. Remember, These mainstream manufacturer's give you the bare bones minimal requirement for the sub box. its for average joes that want bass in as little space as possible. You can definitely stray away from what they state and achieve better results.

 

[Roland 10+ year member]

I'm thinking 3.4 cubes is about it.

 

[Roland 10+ year member]

I guess i can change the length shorter. I don't know if longer is higher, or lower frequencies tuning.

So i assume i should start with a longer port, staying between 38hz and 34hz ???

 

[Jeffdachef 5,000+ posts]

I'm thinking 3.4 cubes is about it.

length X width X height is needed for dimensions. Longer is lower tuned to a certain extent, If its too long, the port will start eating up too much usuable airspace and smaller box = harder to get lower tuning.

 

[Roland 10+ year member]

View attachment 26553439View attachment 26553438

length X width X height is needed for dimensions. Longer is lower tuned to a certain extent, If its too long, the port will start eating up too much usuable airspace and smaller box = harder to get lower tuning.

The box will be 57" long, 14" tall, " 11 wide, EDIT 10" wide not 11", the cross section inside area is 106 sq inches x 55.5" = 5896.87 / 1728= 3.4 cubic feet

(the width is equal to 11" wide but the box is shaped like a house from the side).

I could go back to the originally plain of 2 boxes if 1 box is to long.

One box with one port puts the port right in the center between the front seats, under my center console. That would minimize any obstructions in front of the subs or the ports/port.

I have a 2 cubic foot sealed box and put both W1200Pro in it. It's close to the size i want so i was able to hear and feel how they would perform. So the subs will be facing forward at a 45 degrees angle, firing at the floor under my front seats. Sounds great and no vibration directly hitting my body this way.

I'll try to attach a photo.

 

[germanyt 10+ year member]

Sounds like youre at about 5 cubes gross volume. Probably 4 after dispacement. Since your box is 14 inches tall your port will be 12.5 tall and Id suggest 4 or maybe 5 inches wide. Length will be longer than the depth of the box so youll need to run a 4 inch wide port to 2 inches from the back of the box. Then T it so each side extends left and right the remaining length required. Im guessing but 12 or 13 inches of port length is probably good. Gimme a sec to double check that.

 

[Roland 10+ year member]

Sounds like youre at about 5 cubes gross volume. Probably 4 after dispacement. Since your box is 14 inches tall your port will be 12.5 tall and Id suggest 4 or maybe 5 inches wide. Length will be longer than the depth of the box so youll need to run a 4 inch wide port to 2 inches from the back of the box. Then T it so each side extends left and right the remaining length required. Im guessing but 12 or 13 inches of port length is probably good. Gimme a sec to double check that.

Hold on let me double check my numbers. It came to 3.4 cubes when i broke it down, something is not right

 

[germanyt 10+ year member]

OK so external dimensions being 57 x 14 x 11. It'd be nice if you could get one more inch of width to 12. But as is you'll be at 3.14 cubes before sub displacement. So about 3 net. The port can be 4 inches wide for a total of 50 sq inches of port area. Port will extend 7.5 inches into the box before turning left adn right. The turn will leave the end section of the port at 2 inches wide each side. The 2 inch section will extend another 15 or 16 inches for tuning at about 38 hz. I could have my port length off though. I don't normally design boxes with center ports that turn and because my box depth is usually longer than the total port length.

 

---------- Post added at 06:46 AM ---------- Previous post was at 06:46 AM ----------

 

Hold on let me double check my numbers. It came to 3.4 cubes when i broke it down, something is not right

No you're right. I was estimating gross volume in my head. 3.4 is just about dead on.

 

[germanyt 10+ year member]

So basically the box will be an elongated version of this.

I'd personally lean more toward this design. It's not as long as your box but I prefer ports that don't split.

http://www.caraudio.com/forums/general-discussion/252777-mazda-6-install-2-rf-t1-12s-no-56k.html