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So - I finally have a fold done. Took me a lot longer than I thought. It turns out that folding tapped horns is easy when you don't pay any attention to the dimensions (napkin sketches...). Once you start making more than one fold, things get really complicated really quick. As drawn, the Shiva enclosure only has 5 folds, 3 90s and 2 180s.

It also helps immensely if you remember that there is a pretty-good sized motor hanging off the back of that Shiva, so you might want to remember to make the horn mouth large enough for it to fit in there without hitting anything, like the access panel.... :doh:

I used 3/4" material for the layout and I set the internal width at 12.75" (pretty much the minimum). I am still working on a dimensioned drawing and a cutlist, should have that done in a few days. This design is not too material friendly right now. I think it will take 3 sheets, but I might need a 4th, and some of the scraps are pretty big. That is the price we pay for wanting it to fit between wall studs or floor joists. I am working on an alternate fold that may fit my room a little better (a little shorter and wider).
 

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Very cool. Eagerly anticipating pictures, reviews etc. :)
 

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Progress Update:

Three sheets of 3/4" arauco plywood have been cut up into tapped horn parts for the Shiva X2 build.

Pics or it didn't happen:





I'll get the horn all laid out and the baffle machined this week, I'll probably be able to start assembly on Sunday.

I may not be good, but I sure am slow :D.
 

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Progress Update:

Three sheets of 3/4" arauco plywood have been cut up into tapped horn parts for the Shiva X2 build.

I may not be good, but I sure am slow :D.
Hey... you are doing well. Drive on soldier. How much is the Auauco plywood? It looks pretty nice... a step up from CDX. ;-)

Kevin Haskins
Exodus Audio
 

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Very nice Mike! Looking forward to seeing how it turns out...

On a good note, my compact, proof of concept 30Hz horn performed very closely to how it modeled:

http://www.audiokarma.org/forums/showthread.php?t=276760&page=10

One problem encountered (which I have encountered with my other two basshorns), was that distortion increased below the horn's passband, most probably due to the horn itself...read post 139 on down for my explanation....but for a 6.5" driver, the indoor output v distortion measuements 30Hz and above are quite good...

I currently have no time in the near future to build the 20Hz horn I modeled, but if anyone is interested in building it, I will draw up plans.....

JSS
 

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I paid a little less than $40 a sheet for the 3/4. It is nice wood, but it cupped a little bit on me since it got wet on the ride home from Seattle. The birch I bought at the same time got wetter (top of the load) and potato-chipped really bad.

It is good stuff - the plies are cross-banded, the grain direction is changed by 90 degrees for the alternating plies, and it is nearly void-free. The good face has no knots, the bad face has some knots and tearout, but nothing major. The bad side is up in the picture. It is a softwood ply, not nearly as hard as the birch, but should be fine for this cabinet, and it should actually take a nice finish.
 

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I got a splinter, broke a nail, and quit. :D

Seriously, work/travel/conventions have kept me very busy for the last couple of weeks. I was able to play with my test gear a bit, and managed to figure out some cool stuff, but I have not managed any serious shop time since the wood got cut.

I plan to be in the shop a fair bit this weekend, I hope to have considerable progress made on the assembly. Bracing (as always) will slow me down, otherwise it would probably be a 1-day build.

Silly forum etiquette question:
Would it be preferred for me to document this build in a separate build thread?
 

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Discussion Starter #132
I got a splinter, broke a nail, and quit. :D
You need to try better than that.

"No I didn't. Honest... I ran out of gas. I, I had a flat tire. I didn't have enough money for cab fare. My tux didn't come back from the cleaners. An old friend came in from out of town. Someone stole my car. There was an earthquake. A terrible flood. Locusts. IT WASN'T MY FAULT, I SWEAR TO GOD."



Carrie Fisher was a sort back then.

Silly forum etiquette question:
Would it be preferred for me to document this build in a separate build thread?
I don't care either way, but if you do start another thread, please link to it in this one, so that others can find the connection later.
 

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Hey Mike from looking at that link from maxmercy to audiokarma I saw you had plans for a TH for the Exodus Anarchy. I know you wanted to wait to post them till your measurements but I have a couple sitting around ready for a project and that piqued my interest.
 

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Hey Mike from looking at that link from maxmercy to audiokarma I saw you had plans for a TH for the Exodus Anarchy. I know you wanted to wait to post them till your measurements but I have a couple sitting around ready for a project and that piqued my interest.
Lots of progress on the Shiva tapped horn yesterday. I have the baffle done and the interior completely assembled. While I probably won't finish the cabinet today, I will get most of the way there. I'll try to get a build thread started too. Along with several other issues that got in the way, my camera died on me last nite.

Modeling, folding, and design is also done for the Anarchy TH. As I have tried to make clear in the past, I do not post actual plans until I have built and tested the designs. That way I don't waste people's time with my mistakes. Wood is also cut for the Anarchy sub, I just need to finish my layout and trim things to final size. It is coming too - and will be a quicker build as there is no bracing.
 

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Looking forward to seeing pics of the progress mate.
 

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Yes, please do. Start a thread and describe the design, post a lot of build pics and link to this thread. :T
Please do and don't give me excuses. I sliced open my thumb opening a router bit package and kept building. A little blood makes it sound better. :T
 

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Take your time Mike. Make sure you are happy that the actual build measures like the model and publish as your life permits.

Kevin Haskins
Exodus Audio
 

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Mike. Is your Anarchy TH a single or multiple driver design? I've started to model the Anarchy since I have drivers hanging around for another project.
 

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Anarchy Design:

Single driver per 2.9 cf cabinet, low corner is about 25 Hz. 90 dB with 1 W, 1M, 2pi, and it will take 100 watts without trouble, so 110 dB is within reach. Things get much more interesting with a pair wired parallel and placed in corners running off a modest plate amp (125 dB @ 1M....:D).

As folded, the cabinet is 30" high, 20.125" wide, and 8.25" deep. It is a bit bigger than I wanted, but there is zero wasted space internally and the driver barely fits. There is close to 1/2 a cubic foot of wood in the internal horn dividers alone, I folded 13.5 feet of tapped horn into that cabinet. Only way I could make it smaller is make it shorter, but then it would not play as low.

No drawings or plans posted yet (at least not by me...) because it is as yet unproven. I'll do a complete build thread and post plans when I have taken my measurements and they meet my expectations. I do not want to waste anyone else's time if it is a bust.

Wood is cut and waiting, but the Shiva build is in line first.

Now - I gotta get back out into the shop - I have a Shiva tapped horn to finish building...
 
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