I have been searching around and just can't seem to get a good enough grasp on these so hopefully somebody here can help me. I'm building a box so after the displacement of everything it will be 3cuft. I will be running two Audioque HDC310s D1 and want to tune the box to 35 hz. So my question is how many ports? How long? What diameter? I just don't want to screw this up and have port noise or inefficient ports. I was also wondering if I could just get pvc pipe from a local hardware store and use that and buy some flares online to save some money. Thanks in advance!

lots of people save money by using anything, pvc is one choice, as the port itself then just adapting flares on each end.

In terms of port size based on a 35hz tuning, i can get you close but it may not be perfect perfect perfect because flares come in all different widths and depths.

Just because the ID is 6" doesnt mean that's all u need to know.

lots of people save money by using anything, pvc is one choice, as the port itself then just adapting flares on each end.

In terms of port size based on a 35hz tuning, i can get you close but it may not be perfect perfect perfect because flares come in all different widths and depths.

Just because the ID is 6" doesnt mean that's all u need to know.

I'm sure you could get it alot more perfect then I would ever be able to do so any help would be greatly appreciated. So what do I need to know? My box is going to be 15x15x34 taking place of my jump seat in my regular cab silverado.

i'll just be brief, using 0.75" mdf, this is what i have -

13.5" x 13.5" x 32.5" internal = 3.4277 cubes GROSS

Displacement for each 10= unknown so lets say 0.15 per so 0.3 = 3.1277 cubes GROSS

Port area requirement for square port = 40sqin

Port area requirement for aero port = 26sqin

A single 6" aeroport has just over 28sqin of port area so a single 6" will do.

The port will need to be around 18" long... That's a close estimate for an aeroport.

If it comes to be that u need a slot port which stays along the side of the enclosure, let me know so i can design a box for it.

the sub displacement is .16 but .15 is close enough. Could I do 2 or 3 shorter ports instead of the 18" long 6" port? What would be more efficient?

you will displace more volume by using multiple smaller ports than 1 larger port.

Not only that, but 4" ports would still need to be just over 17" long each.

I know it's almost impossible and not recommended to bend aeroports so if u need to go with a slot port which stays to the side of the enclosure, let me know.

Port area requirement for square port = 40sqin

Port area requirement for aero port = 26sqin

How did you come up with that requierment ?

Port area requirement for square port = 40sqin

Port area requirement for aero port = 26sqin

How did you come up with that requierment ?

x2?

Port area requirement for square port = 40sqin

Port area requirement for aero port = 26sqin

How did you come up with that requierment ?

x2?

x3

Is there any websites I can buy 6" ID flares?

Have you checked partsexpress ?

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=268-354&FTR=6%22%20flare&CFID=15046460&CFTOKEN=21429452 would that be the part I'm looking for?

Using the carstereo.com calculator I came up with a 6in port @ 35hz 15.55in. I did 3 3in @ 36hz at 11.94in, 2 4in @36hz at 13.82 in, and 1 6in @36hz at 14.46in. I decided to switch to 36hz because that is what sales at audioque said to tune it between 36 and 38 hz. I also still don't understand the difference between a single port and multiple ports. The box I am building is 15 high and 15 wide with a front to back length of 35in going in between the seats of my 08 regular cab silverado. Thanks for the help

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=268-354&FTR=6%22%20flare&CFID=15046460&CFTOKEN=21429452 would that be the part I'm looking for?

On the money !

And I have to say, for a kit, it seems decently priced.

Using the carstereo.com calculator I came up with a 6in port @ 35hz 15.55in. I did 3 3in @ 36hz at 11.94in, 2 4in @36hz at 13.82 in, and 1 6in @36hz at 14.46in. I decided to switch to 36hz because that is what sales at audioque said to tune it between 36 and 38 hz. I also still don't understand the difference between a single port and multiple ports. The box I am building is 15 high and 15 wide with a front to back length of 35in going in between the seats of my 08 regular cab silverado. Thanks for the help

When using multiple ports you can imagine that you are using a single port which has the same surface as the multiple smaller ports combined. Surface is what dictates the length when you have a fixed volume and tuning frequency. You can split that surface into multiple smaller surfaces.

I'm a fan of a single big port instead of 2 smaller ports. Easier to fit it inside the box.

but would those work? and is it only opinion or is a single port better than multiple?

General rule is the fewer ports the better. Greater openings mean less port noise/resistance.

General rule is the fewer ports the better. Greater openings mean less port noise/resistance.

You need to rethink that statement.

Sorry.

What I mean is "fewer ports for a given surface area". As in, if you need ~50sq of port area you'll want to do an 8" port instead of two 6" or three 4". Correct?

on another forum I'm being told 3 4in flared ports would be better than the 1 6" if I have room for them due to surface area.

Well yeah, 3*(2*2*3.14) = 37.68 and (3*3*3.14) = 28.26 so you'd be gaining a solid 33% more SA, but say, a 7" port would be 38.5 so if possible you could do that.

So I think I'm going to go with the 3 4" ports flared and do half external half internal. What length should they be and how would I secure them?

I have been searching around and just can't seem to get a good enough grasp on these so hopefully somebody here can help me. I'm building a box so after the displacement of everything it will be 3cuft. I will be running two Audioque HDC310s D1 and want to tune the box to 35 hz. So my question is how many ports? How long? What diameter? I just don't want to screw this up and have port noise or inefficient ports. I was also wondering if I could just get pvc pipe from a local hardware store and use that and buy some flares online to save some money. Thanks in advance!

You can make your own ports out of pvc ,check out www.subwoofer-builder.com