Need help in TH modelling

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Ok, I've finally figured out how HornResp works thanks to the tut above ^^

Here's some screenshots for the Dayton driver



SD compression ratio is 3.37:1. Is it too high?

Comments please :D

I always enter it as a four section model, this provides addditional freedom, and makes it easier to make corrections in the model when you start folding it into an actual enclosure. You can get rid of the big dip @ 100Hz by increasing the driver to mouth distance, and eliminate some of the raggedness in the upper frequencies by shortening L12. The Hornresp Wizard is just an incredible tool.

Also, always take a look at the impulse response of your models.

Hi killa2222,

The Ang @ 0.5 (solid corner placement) coupled w/ the Eg of 2.83V (1W into 8Ohm) gives an optimistically high output. My suggestion would be Ang @ 2.0 and Eg @ 2.0. You don't need the AP1/Lpt fields unless you use a throat chamber (Vtc/Atc).

Overall this looks quite good.

Folding isn't simple but there are plenty of people here and other places willing to help. I only even discovered the TH in mid June and have built a few very sweet sounding boxes, they really blow peoples minds! I started by using my Hornresp numbers and drawing it in 2D in Sketchup it's very easy to grasp compared to ACAD. Hornresp uses metric unit, so if you go to the "Window" tab in Sketchup and select "Model Info", then choose "Units" in the menu on the left, select "Decimal" in the "Format" drop-box then you have your choice of Inches, Feet, Millimeters, Centimeters, & Meters (Hornresp uses centimeters) . Use the dimensions you have to do a rough 2D drawing

An externally hosted image should be here but it was not working when we last tested it.

I usually print out a couple and cut them out and play around until I get something that looks alright and go back to SketchUp and draw it. Then you can get your dimensions by using the Dimension tool and put them into Cut List a very cool/helpful program

You can also read and use Brian Steele's Spreadsheet for Folded Horn Layouts If you like the fold style it uses. There is also great information about measuring the fold corners there

Hope that helps
THANK YOU! This is the best direction I've had so far, esp. how to use sketchup. I will give this a try and see what I can do. All I honestly want to do at this point is take a pre-existing design-the Anarchy exodus tapped, and use a different driver, and change S3 and S4 slightly. I can't seem to print my hornres page, but here is a link to what I want to build. Reed Exodus Anarchy 25hz Tapped Horn - AVS Forum
Again, I appreciate the reply.
No problem :cool: Right now I'm working on a double-folded 15" TH. It's LARGE and being disguised as an antique buffet table, lots of work! The model shows it'll play 16-83Hz +/- 2dB in 2Pi w/4th order LP and 2nd order HP to tame excursion, so in room should be awesome
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Good stuff here!! From what I've observed, most TH width's is almost always slightly wider than the total diameter of the driver. A double fold TH would be massive i think :eek:

Still gonna learn up on TH theory! This is gonna be my year end build because I gotta study up for a huge exam in about a month!:rolleyes:
With Hornresp - simulating a tapped horn is simple. Folding one into a useful shape (and winding up with what you simulated) is where the true kung-fu lies. As nearly every fold is different, there really is not a one-size-fits-all approach that I am aware of for anything more than a single fold. The double-fold method on volvotreter's site is close, but there is a step in area around the first bends.

Personally - I do folding graphically in sketchup, and I do it trial and error. It is not terribly efficient. I draw a lot of doodles, but most of the sketches don't work once real dimensions are used.

I may not be any good, but I sure am slow.
is it safe to say that in a single folded TH the measurements from each side of the turn or the midway point would stay the same or grow only slightly

for instance
in this pic


lets assume that if the height dimension is 10" would the midway point of "L23" be 5" from the top to the baffle, 5" from the baffle to the right side and 5" from the baffle to the bottom board ?

or should it grow something like 4.75" ,5" and 5.25"
It should grow, as there is a length through the corner.

How much? Well, that depends. I recently figured out a relatively quick graphical method to determine how much to increase the area through a corner. Unfortunately, though I have some plans drawn up, I have not had the opportunity to actually build the enclosure yet so that I can test my idea, so I am not sure if it is an accurate approach.
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