12 years since my last box, before I start cutting figured I'd get a sanity check on this design. 2x Ev3 12s in 2x 1.76cf chambers ~32hz

[ExtremeODD 10+ year member]

I'm getting ready to start building a box for 2 Sundown Ev3 12s that should be here later today and figured before I possibly ruin $40 of 3/4in MDF that I'd check with the CA hivemind first. Initially, I was wanting to build a tline but after banging my head against WINISD/Hornresp and getting no where, I gave up and simply copied the bassahaulic refrence design SA has on the Ev3 page. The only change is adding a mirrored chamber on the port side, that way I wouldn't have to do any math for port volume (and have a box built far sooner than it would take me otherwise).

Other than being less efficient than a smaller footprint single chamber ported box, does this design have any critical flaws? Whenever I get a better grasp on WINISD and Hornresp I'll build a different enclosure, for now I just need something to throw the woofers in so I can finally have some solid bass in my ride.

Misc details:
2000 Astro van, both rows of seats removed so space is a nonissue
Pioneer avh-x2800bs headunit
Garbage tier JVC coax 6.5 front door/4x6 rear pillar speakers, JBL stage 6x9 for the dutch doors.
(soon to be installed)
2x Sundown Audio Ev3 12in d4 woofers
SFB-2000D amp
1/0 Power wires, stock electrical (big 3, 2nd battery (if the case repair holds up) and AD244 swap will be on my next day off late next week)

Click to read more...

 

[Buck 5,000+ posts]

You don't need the center port splitter.

 

[ExtremeODD 10+ year member]

Would negating that affect the tuning at all? Its basically 2 of these boxes stuck together.

Also I totally plan on hitting you up in a few months pay for a design for me, as I know that once I get the taste of real bass again, that I'll be upping the ante with something far greater than these wee Ev3s and your work speaks for itself, not to mention the brilliant attention to detail.

 

[Firewalker]

I would just pay him the 30 bucks now and be done with it if you are going to have him do one anyways. He gives you a full set of cut sheets and what not. And agreed that middle divider isn't needed.

 

[ExtremeODD 10+ year member]

I'll leave out the divider and see how that goes. As I mentioned before, these aren't the final drivers that I'll be using, they are more or less something to get started with until my funding improves. It doesn't seem like it wouldn't be worth wasting Bucks time to design a box that will only be used for a few months or locking myself in to a narrow speaker size/allowable ts parameters when I'll be picking up nonentry level subs in the near future. Figured that out the hard way with my previous setup, swapping from the hot garbage hifonic brutus woofers to some okur K9s (along with doubling the RMS) ended up destroying that enclosure.

At the very least, the input on this thread (or rather the lack of attacks on the design) has told me that the box should be functional, minus the center divider of course. I honestly appreciate the input, thank you.

 

[Buck 5,000+ posts]

Just remove the extra .75 width from the port. I'm stacked up right now on designs, got a lot going on.

 

[ExtremeODD 10+ year member]

Wish I would have read that before getting started... No worries buck, I don't plan on bothering you until probably early next year as my woodworking skills are nowhere near where they need to be to pull off a 'buckbuild'. That's the main reason I ripped off the bassahaulic build from sundown's page, no one to bother and if I screw up the cuts it doesn't hurt near as bad.

Currently have the box 80% built, just need to put the top plate on but am exploring different alternative glue/adhesives to ensure the minor variations on the panels seal nicely. All the more reason to get the scrapper over here to pick up my s10 racetruck so I can get the table saw out I suppose.

One dumb question for anyone who is willing to entertain it: How would the tune be affected if the first (rear) sections of the port were approx 1/5-1/4in smaller and the merged port is ~.75 wider than the stolen design? I would think the narrowness would cause a shift towards the higher frequencies but I'm not too sure. That is somewhat shameful to admit considering I'm a decade-old user, but to be fair, my last setup was sold about 8-9 years ago.

I'll post some pictures of the finished build here in a day or two, I never post anything 'in progress' due to my tendancy to do everything in the hardest way possible. The end result is always functional, just the route there is horrific to observe. Also I'm over working with MDF, plywood all the way if only due to hella less dust/wood boogers.

 

[Buck 5,000+ posts]

Wish I would have read that before getting started... No worries buck, I don't plan on bothering you until probably early next year as my woodworking skills are nowhere near where they need to be to pull off a 'buckbuild'. That's the main reason I ripped off the bassahaulic build from sundown's page, no one to bother and if I screw up the cuts it doesn't hurt near as bad.

Currently have the box 80% built, just need to put the top plate on but am exploring different alternative glue/adhesives to ensure the minor variations on the panels seal nicely. All the more reason to get the scrapper over here to pick up my s10 racetruck so I can get the table saw out I suppose.

One dumb question for anyone who is willing to entertain it: How would the tune be affected if the first (rear) sections of the port were approx 1/5-1/4in smaller and the merged port is ~.75 wider than the stolen design? I would think the narrowness would cause a shift towards the higher frequencies but I'm not too sure. That is somewhat shameful to admit considering I'm a decade-old user, but to be fair, my last setup was sold about 8-9 years ago.

I'll post some pictures of the finished build here in a day or two, I never post anything 'in progress' due to my tendancy to do everything in the hardest way possible. The end result is always functional, just the route there is horrific to observe. Also I'm over working with MDF, plywood all the way if only due to hella less dust/wood boogers.

Man, I design boxes to whatever level you are able to build them. Simple boxes can sound just as good as crazy complicated boxes. So if you need simple, I can design simple. It's as simple as that

 

[ExtremeODD 10+ year member]

I'll snap some pics of the finished build here in a little bit, considering I haven't worked with building anything out of wood in nearly a decade it turned out better than expected. Especially factoring in using a circular saw with no clamp on guide (so. much. sanding.) Despite messing up some of the port specs just a touch and keeping them low for breaking in, these things ****ing pound. I do have some serious regrets on not grabbing the 15s instead as the box looks just puny in the van and 15s would allow for far more cubes without over extending the drivers. But since I have 2, and they are dual 6 (according to specs, still need to hit them with the multimeter and see if thats true) I'm going to pick up a third asap and see if I can't figure out a single massive chamber ported box to really feel what they can do. Or flip them locally and grab some SA 15s or a single U 18 (never had larger than 12in before).

Buck, I might be hitting you up in a month or two for a simple enough design, after doing a weird double box by mirroring that design I found, I'm over anything complicated like that haha.

 

[ExtremeODD 10+ year member]

After running these for just over a week, I've gotta admit that they don't hit near as low as the 12s I grew up with. Maybe I was spoiled with a single eclipse tc9 12in with 25mm xmax, then dual okur k9 12s with the same 25mm xmax, where at full tilt a cloud of smoke would shift side to side over an inch during a low note.

I've seen where people have been able to do mutant looking port extensions to lower the box tuning but I've gotta wonder if it would be a waste of time considering the fairly small amount of cubes the box has. I'm also toying with the idea of cutting out the internal chambers to combine them and running a pair of tube vents but again I'm not even sure the ev3 12s could even benefit from that. Winisd hasn't shown me numbers that look too promising in that regard. Or maybe it's just my voltage is dropping a touch too much and when I finish wiring the PWM controller to the DR44G alternator to allow for more than a measly 13.Xv output they may wake up some more. It's hard to say how much power the amp is truly pulling as my hardwired ammeter on the 1/0 input line has a fairly slow update rate and will only ever get past showing 50a on test tones.

I suppose before doing anything drastic I should finish up the PWM alt mod and slap on big 3 using the 4g wire I got for nearly free from the junkyard (cobalt rear battery cable, wish I would have known about the 300 rear batt using 2g) before jumping the gun.

 

[ExtremeODD 10+ year member]

No pics yet, (van is a mess) but after flipping the subs to sit outside of the box to regain a little bit of CF, rewiring to 4ohm (turns out ~2.6k is a touch much to 2x e12 d4 v4 rated at 300rms) and running the alt at ~15v things do sound a bit better but I'm not very happy overall with the setup. I'm debating on if I want to just see what buck could do for a tline (size is no object), or saving up a few bones to grab 3x more e12 d4 v4s so I can wire somewhere close to 1ohm and see where that gets me with a properly designed box. The final thought is to get some proper DSP so I can keep the excursion in check at the fequencies where winisd shows them going nuts at full tilt (and also getting them stinky). From a cost standpoint, I think hitting buck up for a design/rebuilding the box would be the best bang for the buck, followed by some kind of dsp then shifting focus over to habving a fully active stage as the door speakers just cant keep up.

 

[Jonnyswboy]

What software did you design this? @ExtremeODD

 

[Buck 5,000+ posts]

I don't get why people use all this complicated stuff to set their systems up. I do all my tuning manually, no offense. I mean all of it.

I do gains by ear. I do crossovers by ear. I do EQ'ing by ear. I do time alignment by my own measurements, if I do that (not really relevant to how I listen to music). I highly recommend people learn how to tune everything by ear. If you don't know how to do that, then you may not thoroughly know what's going on with your system. IMO, again, not trying to be offense, if you know how to tune everything by ear, then you really know what's going on with your system. I can just jump into any vehicle, for example, and just start playing with the EQ based off the way it sounds. I know what frequencies make what sounds. I really, really suggest you learn how to tune like that; all of these automatic tuning devices don't really know what you're hearing is like, what you truly like out of your sound. There is no "perfect" EQ setup; it's all based around what YOU like.

 

[Buck 5,000+ posts]

All I had was a radio with a 7 band graphic EQ, and had some crossovers on it, and that went straight to the amps, a HO alt, and 4 group 31 batteries. I had no processing, other than the radio's features and the crossovers on the amplifiers.

 

[Buck 5,000+ posts]

I feel like too many signal processing devices over-complicates your system. KISS = keep it simple, stupid. The more signal processing devices you add, the way more complicated your system gets, and then you can run into sorts of compatibility issues in between devices.