So that tip helped you about the error? Like said, type 2 of 3 of the Q values in and let it auto calculate the last one even if it comes out the same it still wants to do it lol!
If you fallow the basic route of box design with simulators like winisd then it will be alright
but theres a few little other things to know aswell and really, it's taste that you learn.
Basically, you want to get the response to look like a straight line for quality transient sound:
That is a VENTED "chebychev" box. It is similar to what they call .707qtc for a sealed box. It is basically in the middle and sounds great and gets low!
Basically, the parts-express page didn't say the qms/qes which sucks, but i went with 5 as the qms and I had it auto-calculate the qes like it loves to do lol.
Heres the page i went by:
The MANDATORY ones are like i mentioned. Usually i put qes, qms and then have it auto calc the qts. Then you cant go without fs and VAS. Those are the basic params you need. When you need it to auto calc the last Q value, you just click in another box.
Then you save it and close the box, go new project, and the new button next to the driver selection list. select the name you saved it AS, which is the filename.
Go through the motions, and by default chebychev is usually default for average subwoofers that do well in them which ofcoarse the axis does.
Referencing the first graph, it looks good and dandy, and the group delay will be low which means the sub will respond "quickly" without smearing at transitions.
But heres a graph of what it may actually be with cabin gain in car:
That is after i changed the box size to 2 cubes from the originally larger box to REDUCE the crazy boost. Not to mention that there is more of a boost that this simulation dosnt show that lies around 20hz and down. Well humans cannot here infrasonic lows well at all anyway and that boost may not bug you. Being that the boost of cabin gain is literally free and DOES NOT make the subwoofer move further or draw more power from the amp and does not achieve it's boost by making the subwoofer work any differently it is a free thing and the even though the db level isn't flat as can be the transient accuracy is still as good as it will be before the cabin gain is introduced. You get it?
But basically, i am saying that things may always look different in reality and asking someone who has built like 8 boxes for the sub can help you out.
You said you wanted good low end, well, basically you will almost always have crazy low end from cabin gain unless you null it with an equalizer or something similar. These subs love this sort of alignment best. The graph with the big gain boost in a 2 cube boxis not what i would reccomend per se, but i did that to reduce the hill a little. It's good for you to know how it sounds with each response to know what you will like.
EDIT: Ahem, this is one of the subs modeled.