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Discussion Starter · #1 ·
original plan was for gjallarhorns but havnt been able to find the plywood easily and the project went stale, also the 60hz ringing issue im not too sure about. im ready to upgrade my single sealed and keep flip flopping on my plans.

have:
2 lms ultras
6 ht18s

just playing around with winisd the ported in a 12cube box can get a solid 120 db. looks close enough till 25 hz then the gjallarhorn starts to take off, but dont you guys usually eq house curves making that higher output moot?

the hardest part is the crazy port velocity to deal with, but seems like it could be done.

dont know what to do with the ht18s, maybe sealed behind the seats, but dont know how well that will integrate.
 

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LMSU ported like Notnyts nearfield but maybe split into two enclosures. HT 18s in Marty enclosures to smooth response and balance out the sound. Thinking that would be pretty abusive :).
 

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I got 135db with my HzHorn nearfield corner loaded @ 16hz with only 400watts and 10mm's of 80mm's of excursion.

Now imagine how loud the full 4000watts would be and/or 80mm's of excursion. 140db? (more???) who knows...

Then... add another 6db to that (because you have two).
LOL

I literally felt like barfing after making that video, it liquefied my organs. (and I'm accustomed to 15+ sealed 18's.) It's beyond ridiculous.

As for resonances: Does this sound bad to you?
(Sounds pretty musical to me)
 

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Discussion Starter · #7 ·
i could be messing up in the simulation but i dont see the huge efficiency gain from the horn. if a ported lms at 15 cubes (if even possible)can output 120db at 20hz and i want a flat or house curve, would the GH just be a waste of space and wood?

im assuming its not possible and would have massive port noise, or the actual tested and theoretical limit is off.
 

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GH is a measured 122dB at 20Hz at 2m outdoors. Winisd defaults to 1m. Change it to 2m for comparison. Long story short either add 6dB full bandwidth for the GH or subtract 6dB for the vented.

2 ported LMS on 2x the amplifier compares well with 1 LMS in a GH. Both can be awesome.
 

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i could be messing up in the simulation but i dont see the huge efficiency gain from the horn.
Some things you won't see in a sim like power compression and port compression. Horns generally have a lot less of both because the horn is usually bigger, the horn flare is larger than a port and the horn requires less power to get it to xmax. Because of this you can see up to 6 db or so extra output from the horn even if a sim shows no advantage at all compared to a ported box. Gjallerhorn is a really small horn so you might not see the clear and very distinct power and port compression advantages that much larger horns have compared to a ported box, but there are still going to be advantages due to power and port compression alone. This isn't efficiency gain, it's more like less loss, but a simple sim will tell you efficiency details if you adjust the 1m/2m sim/measurement details properly as Ricci just advised.
 

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Discussion Starter · #13 ·
Ghorns it is, until then i need a second sub in the other corner.

my workbench is full of diffusers i need to assemble, and the box would block the door sooooo..... lol the wall is coming down but is structural so this is the setup for a bit. i still giggle on how half assed it looks.
 

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GH is a measured 122dB at 20Hz at 2m outdoors. Winisd defaults to 1m. Change it to 2m for comparison. Long story short either add 6dB full bandwidth for the GH or subtract 6dB for the vented.
2 ported LMS on 2x the amplifier compares well with 1 LMS in a GH. Both can be awesome.
and then add room gain.
and then corner load it.
and then tune it lower (i.e. HzHorn)
and then stand right next to the box (LOL :D)

I'm pretty sure I'm losing braincells by the second from this thing shaking my skull and bones (but that's ok... in what is left of my headmovies! :p)
 

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