Hey guys,
this box would be for (3) 12" AQ HDC3 copper coils.
External specs are 15"x34"x32" using 3/4" MDF, that gives me around 7.74 cu.ft. before displacements. Pretty sure that number is right.
Minus the sub displacement which is .18 PER sub, leaves me with 7.2 cu.ft.
I know the 12" AQ's need at least 2 cu.ft + PER sub, so the most space I have to work with regarding port space is 1.2 cu.ft. The less the better, so that the subs can see a bit more air.
I wanna tune to 36-37 Hz. To wire up 3 subs, it will give me a final load of 1.34ohms I think. I have a Clif Designs 4800.1, so I have enough power for the most part.

Would any box experts with a program be able to calculate slotted port dimensions in this case??? I need to find out the Height x Width and Depth, then I should be good to go

Subs will be firing up towards the hatch with a slotted port facing the rear

Thanks

 

port 36hz

height 9.494
width 3.165
length 5.26


port 37hz

height 9.494
width 3.165
length 4.342

hope this helps

 

Really?





Thats so incorrect

 

Hi Jalat,
so what would be the correct port dimensions if I went with a slot port for
the three 12's tuned at 36 or 37Hz ?

 

Remember that design for the two 15"s?

Thats going to the best best enclosure you can do for three 12"s. So like I said, just make a new baffle for three 12"s and use that.

If you are contemplating between 3 12"s or 2 15"s I would suggest getting a pair of 15"s

 

But how could I switch baffles once I glue and screw down the first one?
Wouldnt it be impossible to switch?

 

Use weather stripping along all the sides of the enclosure. Make your double baffle for 15"s woofers.

Using something like T-Nuts, screw down the double baffle for the 15"s. The weather stripping will act as a sealent, like glue does, and the t-nuts will make sure that if you ever take the baffle off, and screw down another one, that you dont strip the wood, and create splits

 

if your figures are external gives 7.259cft leave 7.2cft after disp,vent one 6"
port 2.327" long one flushed end
or rectangle vent height 5.317" width 5.317" length 2.319" one flushed end.
or other area 28.27 sq in, length 2.327 in.all checked on bassbox pro jalat. done at 37hz.
the figures i gave before was also checked through bassbox pro with a guide line of minimum
3 inch wide rectangle port mouth.all done in inches.

figures 15" 34" 32"

 

I cant see how a rectangular port would only be 5.3" x 5.3" x only 2.3" in lenth?
Seems way too small for three AQ HDC3s

 

Wow, his recommendation is close to accurate but going to be hard to let them 3 subs breathe on 4.24" of port/cube....
I also use BB6P, just must have a little more experience with enclosure design and sub requirements....

Make it 13.5"x6"x20.7" one straight port. It'll give you about 13.5" of port/cube. (I'd go bigger still, but not enough room)

Leaves 5.95 cubes after all displacements based on your max dimensions @ 37hz. You might get better results with 2 subs and a larger port.