Did I tune this box right?

[sorry_i_win]

OK... lemme post what I said in my other thread (https://www.realmofexcursion.com/phpB...asc&highlight=)

Originally Posted by bookechu

I wanted to use 3 6" ports on a box for 2 15" L7s and I got replies that it does not have enough port area i was required to use 4 6" ports at about 29" in length to get a frequency of 32hz. How did you get away with using one 6" port that looks no greater than 20" in length for 2 15" h2s. I'm about to start building my box, i will definitely need ur help. do you have aim ?

hmm.. well i hope i did everything right. I used the port length calculator here: http://www.carstereo.com/help/Articles.cfm?id=31 4.4 cu ft box, 6 inch diameter port, 12.5 inch long = 32 Hz. This damn well better bet right after I molded it in there. lol. Should I have only used 2.2 cu ft in the calculator for each sub? hmm now I feel dumb. If so then what the hell s my tuning frequency as is... This is my first real box design. someone care to comment?

[sorry_i_win]

I tried it on this website (http://www.ajdesigner.com/phpvent/su...n_length_l.php) to and I still get 12.5" if I use one 6" diameter port with a 4.4 cu ft box... So what am i doing wrong? Should I only do half the box volume to find the port lenght needed for each sub? Man I wish I someone would have brought this up when I posted pics of the design. If I did it wrong, could I add a couple rectangular ports besided the round one? Sorry that I'm posting this both places... but it's really too seperate topics.

[Reamo04]

it is tuned right, thats not a problem
IMO, i would have done more ports (more port area, more flow)
Sure its a ported box, but its kind of restricted, thats the only thing wrong. Everything is tuned right tho

[sorry_i_win]

I see.. so is this a big deal? Will it lead to distortion, port noise, etc? Will it lower SPL? I'm confused a bit.

[sorry_i_win]

actually.. did a little research and apparently minimum port diameter recomended for my application is 10.59"... this would be about 87 sq in of port area, so I would need around 3 6" ports to equal that... but they would all have to be 43" long which isnt remotely possible. So what size rectangular ports could I add to make things better or should I even bother?

[Reamo04]

i probably wouldnt even bother.
And i'd just do 2 ports. if you calculate it for 2.2 cubes each, theres no way your ports should be that long.
Give me the dimensions of your box and i can see if i can help ya out. 2 6" ports for each sub would be more than enough

[sorry_i_win]

the problem is that the box is already done and there's no room for more ports unless I make rectangular ones. I'm gonna have to just try it and see how it sounds. at least now i know one 6" port for 2 15's = bad idea. blah

[sorry_i_win]

but one thing just to clarify... when you calculate the port size for tuning the box it doesnt matter how many subs are in the box just so long as u use the net volume... right? u dont calculate the cu ft per sub to tune it unless they are in seperate cambers.. right?

[12voltz+-]

idk really know but i would at least give it a try to see how it sounds you could all ways try to sell the box

[Reamo04]

what i would do, is drill holes for 2 more 6" ports (1 on each side or so), and then you'll haev 1 1/2 ports for each sub

[12voltz+-]

that could work ^

[bookechu]

It won't look, by lookin at his pics there is no way he can add another 6" port on either side of the one that is already there. Just try it, it may work. ur only problem is that you might get port noise because of all that air trying to come out of one port...

[Reamo04]

theres 4 possible spots that i see, length might be tricky, but it could be done

[bookechu]

The ones on the top of the box may work better than adding to more on the front. But it is already painted...idk...If you add more ports, remember that you have to make them longer if you want to keep that same frequency..

[Reamo04]

he may be able to do some smaller ports, like 3" or somethin