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designing a new box for 4-10" subs.

the box will replace my center console and continue under the back seat of my Dodge ram.

The plan is to have a box  7-8 cubes tuned around 28hz!  

When calculating my port size im a little lost.

THe box will be one large continuous chamber without baffles or any inside chambers.

How do I calculate the port area for my box?

I would like either 4 ports or one single port! 

They will be round ports!

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How much port area you need is determined by how much net volume you have, how much power you are going to be running, and what frequency you are tuned to.  Software like WinISD or BassBoxPro can help you figure out how much you need.  Or here is a port area calculator I made: https://goo.gl/STAv4p

 

Once you know your port area, net volume, and tuning frequency desired you can determine how long your port will need to be to get that tuning.  Tools like Torres Box Calculator can help with that. 

If you can do one larger port vs four smaller ports, the single larger port will probably be more efficient. 

"Nothing prevents people from knowing the truth more than the belief they already know it."
"Making bass is easy, making music is the hard part."

Builds:

U7qkMTL.jpg  LgPgE9w.jpg  Od2G3u1.jpg  xMyLoO1.jpg  9pAlXUK.jpg

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Total net box size, total watts, and tuning frequency if you use Triticum's calculator. His calculator comes very close to what WINISD will plot based off of more variables (sub specs, filters applied, final impedence, etc.)

25d9cf71-fff8-4b67-a8f5-28c80d5ea859_zps7d3fe7f6-90c4-4939-b709-43f0e5812212_zps

2018 Honda Civic Sport Hatchback (build in progress)

NVX Sound Deadener (Front Doors)
Stinger FAST Rings

Stock Electrical

SSA Evil 6.5's Front Speakers
Stock rear speakers

MB Quart ONX4.80 speaker amp
Rockford Fosgate T-1500bdcp
DC Level 4 12" D1 @ 2-ohm
Box In Design Stage
Stock Radio
My Build Log

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35 minutes ago, mmacleod1983 said:

I understand that part but when calculating my volume do I calculate my box size based on 

 

7 cubes split 4 ways? (Four drivers)

1.75 per sub 

or 7 cubes total ?

sounds like a lot of air space for 10's.is that what you want after displacement and port?

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2 hours ago, mmacleod1983 said:

I understand that part but when calculating my volume do I calculate my box size based on 

 

7 cubes split 4 ways? (Four drivers)

1.75 per sub 

or 7 cubes total ?

For using my calculator it would be total net volume (so 7 cubes), with total power (2000 watts for example), and tuning frequency (like 32 Hz or whatever).  From that info you can determine how much port area you need total, for all four subs together.  

Whats subs and amp/s are you going to be running?

"Nothing prevents people from knowing the truth more than the belief they already know it."
"Making bass is easy, making music is the hard part."

Builds:

U7qkMTL.jpg  LgPgE9w.jpg  Od2G3u1.jpg  xMyLoO1.jpg  9pAlXUK.jpg

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My system was recently stolen by the tow company who towed my truck.

 

I filed a police report and their insurance company reimbursed me $3,187.

 

They took my batteries, cable, head unit, amps, components, subs and enclosures.

 

I dont have a lot to reinvest into my system at the moment so I will be piecing things together that I have from previous builds and buying what I can with the $2000 budget I have given myself based on my family's needs.  (still recovering from Harvey)

 

With all that being said I will be running (4) soundqubed HDS 10 dual 2ohm subs.

I already have the subs so no cost there.

Powering them will be a CT Sounds 3000.1 running at .5 ohm. When wired in parallel I get a resting impedance of 1.67 ohms. ($350 on facebook marketplace)

Up front I have a pair of 4" coax in the dash a set of 6 1/2" components in the kick panels on the floor and a pair of 6 1/2" coax in the doors.

The rear doors house a pair of 6 1/2" coax. ($250 for speakers)

The door speakers are powered by an Eclipse 34230 ($0 owned both of these amps)

The front components and dash speakers are powered by an Eclipse  ea 5422

Have ordered two XS d3400's and have a 160 amp stock alternator ($700)

Big 3 with 1/0 cable and all runs of cable are 1/0 with two runs powering the sub amp. $200)

 

I figured 7 cubes because once you add displacement of subs and ports I will be pretty close to the volume I am looking for.

tuning around 28hz preferred! ($250 for material and fiberglass) 

this will leave me a bit to buy a decent head unit on Ebay!

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Those subs recommend 1.25-1.5 ft^3 Net (after displacement) per sub (if I'm reading the SoundQubed site correctly) and that amp is rated at over 3,700 watts. So for 1.25 ft^3 Net per sub, your box size would be 5 ft^3 Net, and Triticum's port area calculator suggests a minimum of 77 square inches of port area, and an optimum port area of 104 square inches with that box size tuned to 28HZ with 3700 watts applied. If you are going for 1.5 ft^3 Net per sub, then your box size would be 6 ft^3 Net, and Triticum's calculator recommends a minimum of 84 square inches of port area and an optimum port area of 115 square inches.

25d9cf71-fff8-4b67-a8f5-28c80d5ea859_zps7d3fe7f6-90c4-4939-b709-43f0e5812212_zps

2018 Honda Civic Sport Hatchback (build in progress)

NVX Sound Deadener (Front Doors)
Stinger FAST Rings

Stock Electrical

SSA Evil 6.5's Front Speakers
Stock rear speakers

MB Quart ONX4.80 speaker amp
Rockford Fosgate T-1500bdcp
DC Level 4 12" D1 @ 2-ohm
Box In Design Stage
Stock Radio
My Build Log

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Area for a circle is pi*r^2 (pi times radius squared), radius being half of the diameter here, so 2". 3.14*2^2=12.56. So the port area of 1 4" port is 12.56 inches squared. 1 port would probably more efficient than the 6-7 4" ports you would need. One 10" port would work (http://www.bigass-ports.com/category-s/146.htm) as that equates to 78.5 square inches, and aero ports are a little more forgiving with port noise if you go slightly smaller on port area. You can also go with 3 6" ports, or 2 8" ports, with the 2 8" ports being closer to the optimum port area range.

25d9cf71-fff8-4b67-a8f5-28c80d5ea859_zps7d3fe7f6-90c4-4939-b709-43f0e5812212_zps

2018 Honda Civic Sport Hatchback (build in progress)

NVX Sound Deadener (Front Doors)
Stinger FAST Rings

Stock Electrical

SSA Evil 6.5's Front Speakers
Stock rear speakers

MB Quart ONX4.80 speaker amp
Rockford Fosgate T-1500bdcp
DC Level 4 12" D1 @ 2-ohm
Box In Design Stage
Stock Radio
My Build Log

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