View Full Version : BOX help for aq hdc3

06-20-2013, 09:45 AM
Hi, i just bought a 12" hdc3 and a powerbass xa3000 amp...i have an 04 avalanche and im looking to build a box into the factory midgate but am having problems finding the right way to port it. Im looking to build it round 30" wide, 15" high" and 13" deep so i still have room to fold the midgate down...that is roughly 2.5 cubic ft before displacement....i am wanting to tune it to round 36 hz or so being that i read that 38 is best for that sub.
Right now it is in a prefab box which is only 1.5 cubic ft and supposed to be tuned to 40hz yet it wont pick those signals up for some reason but hits lows hard!?
So what i am wondering is do you think that would be a good size? And if so what size should the port be? im gonna be doing a slot port so wondering how wide it should be and how far back it should go. Thanks for any help guys!

06-20-2013, 10:30 AM
You misread it, i dont have a 15" i have a 12" my box specs are right on with everything i have read, 2cubes to 2.75 is best....i could go a little bigger on width, maybe 32" so after displacement it will still be around 2.5 cubes....my question is about the port...idk how to do the cubic inches, im just wanting to know if someone can tell me, if i have a box 15" high, 30-32" wide, and 12" deep how many inches wide should my port be and how far back should it go, and should i bend around the corner and bring it further, etc? Thanks
this specs are not good if its 15'' sub how the height is 14.5''? at least you need to have 16'' height. you need to add woofer displacement. port area you need to have at least 50in^2 and port area per foot at 12-16 range you are to low. and net volume about 3.75ft^3 and 4.00ft^3

06-21-2013, 09:43 AM
Really? Very simple question that i would think a ton of you would be able to answer just off the top of your heads, yet i only get one reply and it seems like he doesnt even speak english nor understand it by the way he answered the question! lol
So PLEASE someone help me out here, all i can find is things saying how many square inches of port space i need but that makes no sense to me cuz it doesnt say how long the port should be or if it bends the corner!

06-21-2013, 10:06 AM
Use this to get your port length. Port Length Calculator (http://www.mobileinformationlabs.com/HowTo-1Woofer-Box-CAL%20Port%20lenth%201.htm)

Don't forget to include displacement for the subwoofer and port when determining that 2.5 cubes overall.

06-23-2013, 10:35 PM
i'll help you out.

1. what are the absolute largest dimensions you have to work with?
2. what ohm are you running that amp at?
3. how simple does the box design need to be? (can you do 45 degree pieces? can you cut PVC in half or fourths the long way?)

06-23-2013, 10:43 PM
Well i never got any help so i just built it already...di 31 wide 13 high 13 deep did a 3 inch slot port runnin back 9inches the makes the corner and is 4 more long. It does what i wanted, wont hit lows worth a crap now but hits the punchy bass crazy hard now!

06-24-2013, 01:34 AM
cuz you're tuned too high, so be careful playing low stuff loud...

06-24-2013, 01:41 AM
Why you want high notes over low notes is beyond me...

06-24-2013, 02:03 AM

Depends upon what you consider high and low. I don't play below 30Hz and mostly play old school hip hop so 40-60Hz punch is what I prefer...