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Dual opposed 18" Mal-X's (X2)

post #1 of 30
Thread Starter 
As a suggestion (You know who you are) I'm looking at 2 boxes with Dual opposed Mal-X's each...

Can I get a couple guys to help model this up and see how small a box I can come up with, giving me a good knee - I don't have WinIsd up and running and have handfuls of projects.... I'm sure someone could whip this up right quick...


Couple of issues that come to mind right off, I have 3 of these drivers already (4ohm SVC), so 2 would go in 1 box. The next batch coming out is 2ohm DVC I would either need another driver to match my SVC, or get 2 new drivers altogether and put a single behind the LP... Plus the new drivers have 5mm greater excursion

Lets see what we can come up with...
post #2 of 30
Quote:
Originally Posted by Warpdrv View Post

Plus the new drivers have 5mm greater excursion

They now have a 37mm xmax?
post #3 of 30
Thread Starter 
post #4 of 30
Oh good, more xmech! Having 32mm xmax, but only 40mm xmech didn't leave much room for error. Now that it'll have 45mm xmech, that should help out.

What about selling off that SVC Mal-x and buying two DVC Malx's when they come out in a couple weeks?
post #5 of 30
Sounds like a killer. Really wanting to drive the wife crazy huh?
post #6 of 30
Warp:

I have a dual opposed Maelstrom. I think I started out with 8 cf. because that was suggested. When I talked to Kevin, he said it woudl benefit with being bigger(to go deeper), and that 12 would be good, and 16 cf. would be even better. I think I ended up at 14 or so. It's huge.
post #7 of 30
Thread Starter 
Quote:
Originally Posted by brandonnash View Post

Sounds like a killer. Really wanting to drive the wife crazy huh?

What the hell is a wife...? Don't/Never have/had one of those....

I find life much easier that way.... Raised my son by myself for the last 15yrs, and he'll be out of the house this summer...
My gf is scared shitless seeing as she knows I'm a man whore !!!!

Quote:
Originally Posted by Fatawan View Post

Warp:

I have a dual opposed Maelstrom. I think I started out with 8 cf. because that was suggested. When I talked to Kevin, he said it woudl benefit with being bigger(to go deeper), and that 12 would be good, and 16 cf. would be even better. I think I ended up at 14 or so. It's huge.

Oh bummer.... I just punched in the parameters into WinISD, and it was looking awful with a 8-10 cu ft...
I'm still not very well versed with WinISD....
That is going to be way to big for me...
post #8 of 30
Just curious, is there something you are trying to get out of the dual opposed maels that your sealed aren't giving you now? Trying to get extra space and not lose output?

My driver and PRs will be in on Tuesday. If I like it enough I might just have to build another and will buy your SVC off ya to match this one
post #9 of 30
Impedance Plots and FR to follow...shortly.....but 11.5 cuft seems at first to offer the best output vs performance. What amp are you planning to use?
post #10 of 30
Thread Starter 
I Wouldnt mind a couple dual opposed and elliminate one sub....
Still keeping a single sealed behind the LP.
Was just thinking about consolidating if it were possible.

My output is already pretty wicked, id like to ask Michael Hurd he can give some honest impressions from when he was hangin out.
post #11 of 30
Thread Starter 
Quote:
Originally Posted by mayhem13 View Post

Impedance Plots and FR to follow...shortly.....but 11.5 cuft seems at first to offer the best output vs performance. What amp are you planning to use?

Thanks mayhem, I have 4 crest 8002 amps here
Each delivers a very solid 4000w @ 4ohm
post #12 of 30
Hey Warp. how big are your current sealed Malx's?
post #13 of 30
Here's dual opp MalX's in 11.5 cuft each run with a single side of your 8200's considering the single 4ohm VC. Probobly no SSF needed either....It's a big box though at 30inch cube.

Attachment 143616

For s#*t and giggles here's a single Malx with two AE 18" PR's in a 24x24x30 box with 2kw power

Attachment 143620

Attachment 143621

It needs an SSF 12db/oct centered at 15hz but man.....that's a serious sub. The PR's mass loaded to 2300g each. Considering some room gain although i know your room is BIG that's nearly flat out to 14hz in reality. Adding a pair of PR's to all three of your sealed Malx's would be quite a shock.

P.S. i just went back through your build thread and even in your current boxes if they're 6cuft each.....still works better than sealed for an adde $250 per box for the PR's
LL
LL
LL
post #14 of 30
Quote:
Originally Posted by Warpdrv View Post


Raised my son by myself for the last 15yrs, and he'll be out of the house this summer...


Where the heck is a 15 year old boy gonna go?
post #15 of 30
Quote:
Originally Posted by Kanaris View Post

Where the heck is a 15 year old boy gonna go?

Maybe he didn't raise his son alone for the first 3+ years only the last 15.
post #16 of 30
Quote:
Originally Posted by dhgilmer View Post

Maybe he didn't raise his son alone for the first 3+ years only the last 15.

Someone is thinking outside the box!
post #17 of 30
Thread Starter 
Quote:
Originally Posted by Kanaris View Post

Where the heck is a 15 year old boy gonna go?

We were together for a while after his birth, about 1.5 years, then she had to go . He was 2 lbs at birth, rough start..... but then I got custody after 3 years old and I have taken the reigns ever since.... Off to collage now... Time served - he just turned 18 and is going to live with his mother and sister to give him a little perspective on life = that its not always all cake...

Quote:
Originally Posted by dhgilmer View Post

Maybe he didn't raise his son alone for the first 3+ years only the last 15.

Quote:
Originally Posted by Erich H View Post

Someone is thinking outside the box!

Hahah You guys caught it...
post #18 of 30
Thread Starter 
Quote:
Originally Posted by mayhem13 View Post

Hey Warp. how big are your current sealed Malx's?

They are Dan's 24" cubes, heavily braced, so about 6^3 net... Powered by Crest 8002 x4

Quote:
Originally Posted by mayhem13 View Post

Here's dual opp MalX's in 11.5 cuft each run with a single side of your 8200's considering the single 4ohm VC. Probobly no SSF needed either....It's a big box though at 30inch cube.

Attachment 143616

For s#*t and giggles here's a single Malx with two AE 18" PR's in a 24x24x30 box with 2kw power

Attachment 143620

Attachment 143621

It needs an SSF 12db/oct centered at 15hz but man.....that's a serious sub. The PR's mass loaded to 2300g each. Considering some room gain although i know your room is BIG that's nearly flat out to 14hz in reality. Adding a pair of PR's to all three of your sealed Malx's would be quite a shock.

P.S. i just went back through your build thread and even in your current boxes if they're 6cuft each.....still works better than sealed for an adde $250 per box for the PR's

That all looks good, but I'm a sealed fan.... no resonating designs... which is why I was looking toward the dual opposed.

Someone a while back had said something along these lines and it stuck with me, I forget who it was...

Quote:


I prefer not to have a port contributing in any way to the sound signature presented, give me a driver system that retains its air spring/driver loading. I also would rather have a manageable, heavily braced cabinet size, where the rear wave is isolated from the front wave. For my bass reproduction I'd rather not hear the subwoofer, just the sound.

I appreciated those words of wisdom, and it really made sense to me...
I'll forgo any lack of efficiency though design and overcome it with brute force, hence the massive power plants. The thought of Dual opposed seemed to be the next step if I could accommodate the fixtures in my room being more efficient.
post #19 of 30
Start cutting some wood Warp! It takes quite a bit.



But you end up with a very capable sub!

post #20 of 30
How do you move that sucker around? Sure is nice looking thought! Good Job!More details on the two smaller box subs please?
post #21 of 30
Quote:
Originally Posted by mayhem13 View Post

!More details on the two smaller box subs please?

Looks like MFWs?
post #22 of 30
Quote:
Originally Posted by mayhem13 View Post

How do you move that sucker around? Sure is nice looking thought! Good Job!More details on the two smaller box subs please?

Thanks--the granite top comes off, which makes it barely moveable with two strong guys for short distances. I am moving it out of the theater when I get my other LMS done, and my niece's boyfriend is getting the nod to help(he's a 260 pound NCAA hammer throw guy).

Like Tack said, the other two are MFW-15's that I no longer own.
post #23 of 30
Quote:
Originally Posted by Warpdrv View Post

They are Dan's 24" cubes, heavily braced, so about 6^3 net... Powered by Crest 8002 x4



That all looks good, but I'm a sealed fan.... no resonating designs... which is why I was looking toward the dual opposed.

Someone a while back had said something along these lines and it stuck with me, I forget who it was...



I appreciated those words of wisdom, and it really made sense to me...
I'll forgo any lack of efficiency though design and overcome it with brute force, hence the massive power plants. The thought of Dual opposed seemed to be the next step if I could accommodate the fixtures in my room being more efficient.

A stuffed 8 cubes is fine.

Bosso
post #24 of 30
Thread Starter 
Quote:
Originally Posted by bossobass View Post

A stuffed 8 cubes is fine.

Bosso

Oooooh.... one of the Peeps I really wanted to make a pit stop here... Thanks Bosso - One of the kings of Dual Opposed, could you help me crunch the numbers on this... ?

8 cubes I could do.... Internal I assume ?

Who's got some measurements for me on this...... Bosso, how do you set this up to have a good knee, I have the SMS-1 to boost the lows. Call me lame but I like to keep it simple...

I could do 2 - 30" or 32" x24"x24" which give me 10 or 10.6 cubes external, then I'll have to subtract drivers and bracing....
I'll have to work up the numbers on driver and bracing
post #25 of 30
Dual opposed drivers, "Submersive and Bosso like subs", highly rated. Why instead of opposed placed drivers on the box you can't do front mounted dual drive subs like the JL Gothom? I was going to do a PR18-2100 set-up in a
7-8cf with the AV15X sub but maybe is better a dual AV15X sub in the same size box fully stuffed? I need one "good" sub (only one space available for placement) to cover a big size room. Both set-ups within $50 of each other.
Having a big room means not much room gain which means the dual drive set-up would need eq. in the low bass to get a flat frequency response in the room, unlike the PR set-up, right?
post #26 of 30
I'm sure someone can post the computer software models but there is nothing to be gained by increasing the box size by 50%.

You'll gain 2dB below 30Hz and lose 1dB above 30Hz. The extra output below 30Hz still requires higher excursion. The sonic difference is inaudible, the size difference is another story altogether. I'd rather keep the box size manageable and dump another KW into it for transients, which, IMO, is one of the SQ requirements that's at the top of the list.

I use a Bassis or a modded Bassis. Sorry, I have no idea how the SMS works. Either way, I'd use a sub you have now with no EQ applied and do a close mic sweep with the mic 1/2" from the dust cap, on axis, and smooth the graph 1/1 on REW. I would then do a sweep with the mic at the LP with no smoothing.

Between the 2, you can plan what to do with signal shaping ahead of completion. I may be building exactly such a beast later this year.

What is the VC configuration for the M-X?

Bosso
post #27 of 30
Maybe Kevin Haskins will chime in here. I built mine to the size he suggested.
post #28 of 30
Quote:
Originally Posted by spanish68 View Post

Dual opposed drivers, "Submersive and Bosso like subs", highly rated. Why instead of opposed placed drivers on the box you can't do front mounted dual drive subs like the JL Gothom? I was going to do a PR18-2100 set-up in a
7-8cf with the AV15X sub but maybe is better a dual AV15X sub in the same size box fully stuffed? I need one "good" sub (only one space available for placement) to cover a big size room. Both set-ups within $50 of each other.
Having a big room means not much room gain which means the dual drive set-up would need eq. in the low bass to get a flat frequency response in the room, unlike the PR set-up, right?

Front drive has some advantages, but it doesn't outweigh the advantages of dual opposed.

Stay tuned for a run down of the AV15H in the Raven thread (If JJ would be so kind as to get me my drivers. I may fly up there and lay up my own pair in his shop if he takes much longer )

I have done some prelims on the first pair I got. I'm holding off for the replacements before I say anything, but, it looks like it may be interesting info for some.

JJ is the PR king. He obviously had PR in mind when he designed the AV MKII series, but... well, we'll see soon enough.

Bosso
post #29 of 30
Warp,

You are still running an amp bridged on each driver right? Just adding the final 4th Mal-x to go with the 4th 8002 and reconfiguring the enclosures right? If that's the case you have so much power on tap that small changes in the sealed box size really won't matter much. My quick modeling shows that the 8002's can get the Mal-x's up past xmax <25hz even in a 3.5ft box. Just EQ up the low end a tad to compensate for the smaller box. Smaller box will be somewhat safer from over excursion. There is some data that suggests that the smaller box will have more distortion, ASD or otherwise, but how audible that will be with <30hz freq's and the SPL levels involved with 4 18's wanging away is up to debate. I'd say anywhere from 4ft to 5ft per driver should be good and adding a Bassis per Bosso might be worth a look.

You still running the HPF?
post #30 of 30
Thread Starter 
No buddy, I removed the HPF.... I'm running the SMS-1 boosting the 20hz range up 5-6db....

Don't get me wrong, I have tons of output from what I have right now, I was just wondering if I could eliminate one of the boxes by going with a pair of dual opposed, and still running a 3rd sealed behind the LP.... Maybe the pair of dual opposed with a single sealed won't offer me more then what I have going right now. Wondering if there was anything more to gain with Dual Opposed or not.

Would I gain output enough to eliminate one single sealed box location, If not I'll stick with this setup... The outuput from the Mal-X's is wicked but only when I get some really really low material, like the Skedoosh scene is getting one of my drivers complaining... but only super low stuff.... Maybe I'll just keep my sights set on the 09 LMS's for that serious excursion I'll likely need, with my extreme output needs.
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