MAG-nanimous

From what every one has been saying I have come to two conclusions about my build. It's either ditch one of my 3 subs and just build the box for two which should give me the extra bit of airspace needed for the port to tune down to 35Hz or keep all 3 but set the port to tune at around 40Hz. I read somewhere that usually 40Hz and above is what is used for spl competition and anything between 30 and 35Hz is best for daily use. Can someone set me straight on this. Thanks so far for everyone's responses. EDIT: Exposport, I noticed on your calculator the tune frequency would change drastically just by flipping the value for height and width. What I mean is, if I put 2 for height and 12 for width and then a certain length it will give me one frequency but if I put 12 on height and 2 on width the frequency will change. Is this correct? Thanks.

Thanks for that explanation. I noticed in the calculator the Port Area Range values would change after I entered a port dimension. Once those values change that's where I started to get lost. Back to your suggestion, 2 x 10 x 20 would decrease my airpsace of 2.25 down to 1.7 but you said that the enclosure should still be fine even with the port? Would the tuning be altered a bit or would it still be close to around 35Hz? The only reason I played with the short ports was because the calculator stated that's what the ports would be tuned at and I wanted to retain as much of the 2.25 as I could. Thanks again.

That actually brings up one of my other questions that I have been having for awhile. How exactly is the port area calculated for a slot port and what is a value that should be achieved relative to the size of the enclosure? Thanks.

Here's the box. The missing board is where I plan on placing the ports. I plan on using the bottom board as part of the port wall. I was also playing with the idea of using the sidewalls of the box as part of the port wall. But like I said, I'm still learning and not sure which part of the box to use as the port wall. I also have a design for a wedge box that's the same as this. It's going into my magnum and I will be having subs fire up and the ports fire back.

I'm not going for too much spl, just more spl over a sealed box. In any case, I can always draw up an alternate design that has it in one chamber. Just delete some segments from the sketchup model. But for now I would like to keep it as three chambers and ports.

Well it's going to be one single box but each sub will have it's own chamber and port. The external dimensions of each chamber if they were seperate would be 17 x 13.5 x 22.5. Hope that helps.

I used sketchup to plot out a box design I want to build for my 3 12" kicker comps. Kicker suggests 2.25 cubic feet per sub for a vented enclosure. I used ExpoSports calculator and according to the suggested port dimensions from kicker it's tuned at around 41Hz. I want to tune the port to 35Hz. Again using ExpoSports calculator I was able to find at least four different port size variations to get me to or close to 35Hz. H x W x L 1. 2 x 6 x 8.5 2. 1 x 12 x 9.3 3. 2 x 8 x 13.2 4. 4 x 4 x 11.8 What I want to know is which of these port sizes would be the best to use and maybe any other info I may need about port tuning. I'm leaning towards the 2 x 6 x 8.5 port but don't know what will cause port noise. Thanks in advance.

I've tried winisd and the driver database either isn't complete or it isn't accurate. Bassboxpro sometimes doesn't even load properly especially under vista. There's user here named "Thumper" who buids boxes and his site mentions that he uses a program called termpak but I haven't had any luck finding it. Also in winisd it only gives you the choice of a square or round port. I want to make slot ports and flare em. Thanks so far for the responses.

I was wondering what programs or formulas many of you use to make enclosures? Do you use the manufacturers suggested box dimensions and cubic feet requirements or do you plug in the thiele small parameters into a program and let that program tell you the kind of box to build? Thanks for any answers.

Your other option for that same enclosure would be to just seal it. If you still have the manual for the cvr's it tells you what cubic feet per sub and port area you could use for them. I have 3 12" comps in a ported box and my external dimensions are way bigger than what you have.