Modeled a couple boxes, let me know what you think.

I bought two of these. Dual VC subs from Fi, called the X (2in VC, as opposed to Q that has the 3in so should be a tamer version with better SQ?)

12 DUAL 4
Fs: 25.7 Hz
Re: 3.9 Ohms/coil
Qms: 4.01
Qes: .38
Qts: .35
Mms: 120g
Cms: 3.2mm/N
Sd: 480cm^2
Vas: 104.1 l
Spl: 88.6dB 1W/1m
Bl: 20.0 N/A
Xmax: 16mm
Rms: 300W
Sealed box: .9-1.3 cuft
Ported box: 1.6-2.2 cuft
Sub OD: 12.500
Cut ID: 11.125
Mounting depth: 5.750
Displacement: 0.10cuft

I wasn't sure if I want these in the same cabinet or not, and originally these were recommended to me by another member for an SVS clone (their tripple ported dual 12 sub). I may or may not do that later, but for now I want each in their own cab so I can use them under my mains for both aesthetics and speaker stands. Also I would like to run them in stereo once I get a good amp (or two monos).

Here's what I came up with as a best compromise for space v. curve.

Vented: 110L, 19hz, 1x 4in port of 20 inches.

Sealed:90L

SPL:



Group Delay:


This sub seems more cut out for vented boxes, though I'm still leaning sealed. It does drop a bit quick, but I'm assuming with room gain it'll even out a few dB. The difference in SPL between sealed v. ported doesn't look like a lot, though the group delay is insane for vented! I read as much as I could about it, though nobody has any concrete info on what Hz v. ms is audible, but I think i'd rather have the quick response of the sealed box down low. I like to believe I can hear that kind of stuff.

Whadya guys think?


Ps. looking for a good amp as well. Doesn't have to be 2ch, but it does have to be inexpensive. E-bay?

It is a cheaper version with less power handling. And more accuracy at lower amplitude - no?

I don't imagine I could drive the Q as accurately in my room with the same power, that's what i was getting at.

So that aside, what did you think of the curves?

Actually I had a question about that. What represents the port air speed?

WinISD help doesn't work in Vista, even when I run the program in compatibility mode (otherwise it doesn't work for me period)

When does it typically become an issue? I have 0 experience with DIY ported cabs.

So if a 6 is enough for a good 15, a 4 ought to work for my 12 "in real life"?

Also do both curves look OK? How far down should I be at 20-30 hz with a well matched 12" + enclosure? (very generally speaking of course) Everyone says that you don't want a perfectly flat curve, but both - especially the sealed look pretty steep to me.