Folded Horn CAD Files for 18" sub?

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Hey Ya'll,

I'm curious if there are any proven "good" folded horn enclosures available as a CAD file or series of .dxf files that I can have cut via CNC for 18" subs. I would then want to assemble them myself. I'm exploring this idea VS buying an enclosure.

Goals to meet are:

Price
Performance
Time

Assume these are for techno parties with a very sloped sound in approximately 1k sqft rooms.

Advice is welcomed since these are the first subs I'll have built.

All the best,
- JP
 
Okay I've done some research.

Thanks so much for the response more10! I'm such a newb lol. Looks like I want to make a folded horn aka scoop. I can use 18" speakers or 20" speakers. Total budget is 3k, so this could get fun :) that has to include a digital crossover and amps though. I have access to a free CNC operator and setup so that's huge.

I'm going after 32hz as my target LF ( a little roll off down there is okay, just not too heavy ). the upper roll off can be something like 300hz, if you think that's wise. Not sure what a common number is for the upper cut on folded enclosures for night clubs. I think my fold is too short, it's about 6 feet from the speaker to the center of the mouth roughly. I attached a quick sketchup I made in Rhino 5.

looking at speakerplans.com I'm seeing it might be difficult to achieve my LF at the size I want. I was hoping for a 4' tall 3' deep 2' wide enclosure. What is realistic at this size?

My current questions are the following:
How long does my fold need to be?
Is the length of the fold measured from the center of the speaker cone to the center of the mouth?
How big does the mouth have to be?
What spots should I use as taps if any?

:eek::hbeat:
 

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If you are new to this, don't design your own. Just choose an existing design.

You have both horn length and exit area to consider. Very often you stack horns because it is impractial to build o bass horn in one piece.

If you build 4 Super Scoops you will reach 30 Hz. Speakerplans.com

Hog scoops are also quite popular. Hog Scoop

I have a Crown xls 2502. Its a monster. You can probably fees 8 scoops with it. It is 2 ohm stable. Built in dsp for filter and eq. Crown XLS 2502 – Thomann United States. The limitation is cone exursion, not the current through the coil.

2,5 K left for horns and drivers. You will probably need 2 sheets of plywood per cabinet, just guessing. That is 150$. 3/4" Birch 4'x8' Plywood G2S - Made in USA

PD.1850 is 450$. Precision Devices PD.1850/2 – Thomann United States

600 $ per box. 4 boxes. You are set.

A caveat. All scoop horns have a dip in the frequency curve when the front of the cone is out of sync with the horn. A hog horn probably has the dip around 100 Hz.

You will also get two impulses from a scoop. One from the front and one from the horn. But these are not intended for hifi right? :)

The alternative is a frontloaded horn. Mogales 1850: https://www.speakerplans.com/index.php?id=1850horn. No dip.

Learn to use hornresp. Try to simulate the hog scoop. When you can do that is simple to simulate 4 or 8.
 
I'm going after 32hz as my target LF ( a little roll off down there is okay, just not too heavy ). the upper roll off can be something like 300hz

Many of the "higher-order" designs are not going to cover such a wide range. Think two octaves, max. 40 Hz ~100 Hz is a common goal. If you want to go wider, then you've gotta think vented or perhaps OSTL.

looking at speakerplans.com I'm seeing it might be difficult to achieve my LF at the size I want. I was hoping for a 4' tall 3' deep 2' wide enclosure. What is realistic at this size?

Going Low + Going Loud requires Going Big. No shortcuts unfortunately.

My "B4" TH went down as low as 33 Hz, but required a box that was about 40" x 32" x 21" to do so. It showed promise, but never went past prototype, but it should give you some ideas to work with. More information at this link:

The Subwoofer DIY Page v1.1 - Projects : "Proof of Concept #4"
 
Do peoples mid range cabinets generally go down to 200hz? I need to consider what go's on top of these.

my friend drew up a super scooper so I guess I have the file I'm after :nod: It's about 100 times better than my drawing :p
he's going to have autoCAD output precision cut plans and I'll do a lot of it on a table saw. CNC for the the handles and speaker cutout.
 

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Can you cut angles on the table saw? You will need pretty good precision on the saw too.

Find nice two-way boxes with a 12" and a horn. Plenty to choose from. This is just one example. JRX212 | JBL Professional Loudspeakers

I mean, it's a royobi but it has some angle cutting options with moderate accuracy.

I'll get the subs done first and then move on to building some mid/hf cabinets :) Might get some extra wood laying around from the first project
 
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