Help deciding what woofer size

[UnIbOnGeR]

so I got an 04 grand prix, I got 20hx35xwx24d that will slide in, need some help on deciding woofer size and how many I would like to go to 2 15s but idont see it doable I tried usin winisd its like readin Chinese when I start thinkin port and woofer displacement my ? is based on box parameters would ya go 1 15, 2 12`s, 2 15`s heck I dunno I like rap and listen to some decaf I like the lows and I been tryin just to find a box designer no one responds like pwk designs ram des etc, joe x was kind enough to respond via pm but I figured I would post to the community rather then buggin him via pm, as for power I got an Rockford t10001bd for the subs as of now, but thinkin upgrading to a cendo 2k depending on woofer choices and impedence im strongly thinkin soundqubed HDC3.115 or 12`s heck w/e I need my brain is bleeding ive been reading for a week and still at square one (my username may have something to do with it lol) but sh1t what would you guys do? I also done big 3 mechman alt for power any input would be precaited thx guys I should mention I could get more room if I wall the trunk getting more space ahead of wheel wells and fitting the 2 15`s and prepared to do it but im thinkin im bitin off more then I can chew already im goin in circles but before I go in anymore circles ill jus hit post and get some input thx for lookin and a kickass forum thx guys

[sbg]

Well if I was you, I would go with a pair of 12s. 2-15s is hard to do in a trunk in the right way. Seal them off from the trunk. Take a look at the hds300 from soundqubed. They will work well with you power and still take more power if you upgrade. Go for a box around 5cuft after sub/port and tune to around mid 30s. I think you will be happy...

[alaskanzx5]

A pair of 12s would be easier to fit for sure. Could do a single 15 but 2 15s would be a challenge in a trunk. Nor impossible but get more experience under your belt before pushing your limits with harder builds

[jarrius]

2 12's or 1 15

[UnIbOnGeR]

so ive decided to go sundown Z v.3 18d2 tuned to 32hz if anyone could check my numbers id appreciate it my overall allowable dimensions are 20hx35xwx24d the sub needs 4.5cuft so in winisd I entered parametrs and based on slot I went and multiplied 4.5x 16 for port size wich gave me 72 so I went 72divided by 18.5H wich gave me 3.89 I rounded to 4.0 to try to make life easier win isd calculated 36in of port length. so then I went 18.5X4X36=2664cuin so I then went 4.5x 1728 to get cu in=7776 and added the 2 together and got 10440cuin for total volume so I went 18.5x33.5 and divided them against total volume determined my depth to be 16.84inches internal volume I think im on the right track but then I look at win isd sais my peak is at 43hz im completely lost now I been at it for 3 hours this cant be right if anyone could tell me where I went wrong id appreciate it or is this normal for an 18(it cant be) lol im lost and if it is right the port needs to go how deep in box? or wider to make total dimensions flk I dunno im gonna try adding a screenshot see how that works out... no scren shot but its a long wave barely any drop peak is 2.743db at 43.40hz and at 100hz its at 0.92db thx for lookin

[UnIbOnGeR]

so I think I figured it out the box was just to small I went 6cubes tuned to 32 and itll fit and peak is at 36hz, inner dimernsions 18.5x33.5x21.5now the port is asking for 18.5X5X32.46 so how would I calculate port wide I jus go back 16.5 and L it and 16inches in?or widen it and shorter hell this is where im lost anyhelp would be precaited what a learnin curve I hope im goin in the right direction

[gr8handogoatness]

I think you will get better results with 2 12s in a trunk than an 18. Its just too big and need too much space to really work well in a trunk. To have enough you really need to seal off the trunk from the cabin and fire the subs into the cabin which won't work with an 18. Its too tall to fit. Do what you want but like others have said and I said, 2 12s will probably be your best bet. It will be the easiest way to get the results you want. If you are determined to do an 18, good luck, I hope it performs well.

To answer your question about the port, yes you will just make an L shape. If you want it to be shorter you have to have less port area, not more. Usually you want to stay away from having less port area so having a long port is necessary. Using Win ISD look at the rear port air velocity. You are gonna want that to be down below 80fps. I like to stay below about 60 but in my experience its above about 80 that you start hearing the "chuffing" or port wind. Some say otherwise but I haven't personally had that experience*. Also if you build it, take a router and round the port walls, it will help better flow, and 45 the corner.

*(disclaimer: I don't actually know the air velocity, only what the model shows and said it would be, so I am judging by the model.)

[youngbass98]

Why a 18 there is no good way to fit that in a trunk with out building the box in the trunk and having the trunk rattle like no other