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I have an 18" MAL-X Gen II build in a 24" sealed cube (http://www.hometheatershack.com/forums/sealed-subwoofer-build-projects/19146-another-sealed-mal-x-build.html) that has outlived its original purpose. When built it was to be my only sub, but as things work - curse you all - it is no longer sufficient. Since the build it has been placed in climate-controlled long-term storage and I have moved to Cambodia for 2 years. I am asking for advice now because the MAL-X is no longer in production and by the time I return to the States memories will have faded within the community and I will be ready to build.

I am in the process of completing two sealed 16" cubes using the Eminence LAB12 driver for my residence in Cambodia (http://www.hometheatershack.com/forums/sealed-subwoofer-build-projects/50162-two-lab12s-sealed-build.html). When I return to the states I will scrap the boxes and build four sealed 16" cubes using baltic birch.

Bass from four LAB12's models above 120 dB (+/- 2 dB) to around 40 Hz - cone excursion limited at 300 W/ea with a 2nd order HPF at 20Hz. So, I am looking to build a sub using the MAL-X to supplement below 50 Hz. Looking to go as low as feasible (I would define as good in room response at 10 Hz or so). Will buy whatever power is required to drive the beast.

I have been reading a lot about tapped horns and they seem to fit the bill. I modeled a sealed build with LT in WinISD, but cone excursion would limit output far below the combined output of the 4 LAB12's (at least in WinISD).

I have searched - and researched - the forum and read mdrake's tapped horn build. I also read a few hints about a member who was building two tapped horns with this driver.:yikes: Lilmike over on AVS indicated that he would go for a tapped horn with the MAL-X. As he is a horn guru I believe this is the way to go. He also indicated HTS has a documented build.

Is there a thread with cutsheets and good pictures to the actual building process?

Is there a better way to go? I have modeled a 15.5 cu ft ported build (17 Hz tuning) that looks pretty good, but it seems that the tapped horn is in another league. If I cannot get a lot of :help: on a tapped horn design this is how i will go. I am not very good with computer modeling and such...

Thank you for any thoughts and assistance.
 

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Thanks for the link. I read that thread and the design thread a few days ago. After re-reading it today it seems that all the data is there, I will need to figure out how to use sketchup to get all the dimensions.
 

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It will definately be big! Since I plan on using it up to about 50 Hz I should be able to put it in corner in the rear of the room. It will be a challenge to incorporate into the space, but the performance gain is substantial.
 

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I just read Ricci's build (Gjallerhorn over at DIYforum). Looks like another impressive TH and over on AVS he suggested the Mal-X will drop right in....looks like there are options.
 

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I just read Ricci's build (Gjallerhorn over at DIYforum). Looks like another impressive TH and over on AVS he suggested the Mal-X will drop right in....looks like there are options.
Can you please post a link ?
 

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Here is the link: http://www.diyaudio.com/forums/subwoofers/189784-gjallerhorn.html . Looks like a well thought out design.

I am also looking into a T-TQWP design for the driver after reading this thread: http://www.diyaudio.com/forums/subwoofers/185836-3015lf-th-35-40hz-but-only-20-deep-help.html .

I have received feedback from bjorno for a 12.25 cu ft T-TQWP design with the Mal-X that has an F3 of 16 Hz (w/ 4th order HPF at 12 Hz). T-TQWP is a lot easier to build than a TH, but I am trying to gather more information about overall performance before I decide which way to go.
 

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Discussion Starter #10
Hornresp model for both the Gjallerhorn and the T-TQWP design. I am still pretty poor at using hornresp.

Is there a way to add HPF and LPF's in hornresp?

When I change the input voltage the SPL curves start to get really funky, is this because I am doing something incorrect - or does it suggest these designs have a very narrow power range (which I doubt as it would seriously limit utility of the designs)?
 

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NavyDoc the Mal-X 2 doesn't look as good as I remember in the Gjallerhorn cab. I may have been looking at the generation 1. It's not bad enough to be unusable but the Mach5 UXL-18 and LMS 18 look much better. Also I would personally not use the other design shown in your last post. It doesn't seem to offer enough of an efficiency or output advantage over a simple ported cab to make it worth while. Not to mention the dramatic gulf above 60Hz. A ported cab could be used up to 150Hz easily if done right. You might be better off starting with the Gjallerhorn HR specs and adjusting them to better fit the Mal-x 2.

Also the max spl tab does not operate te same as the ones in other programs in HR. It assumes constant power but systems operate on constant voltage in the real world. The MX should take 90 volts in the GH cab down till 14Hz.
 
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