jwc Posted February 10, 2007 Share Posted February 10, 2007 So from what I gather...those top and bottom panels of the horn need to be somewhere between 11.5 or 11.75 inches so that the length of the horn is right at 11.5 inches. Am I off here Ajsons? jc Quote Link to comment Share on other sites More sharing options...
ajsons Posted February 10, 2007 Share Posted February 10, 2007 At that point (11 inches from throat), the sidewalls are almost at 90 degrees to the axis. Like you said, it's not a big deal. I have an autocad drawing of this jc. I'l find it and post a printed copy. Quote Link to comment Share on other sites More sharing options...
jwc Posted February 10, 2007 Share Posted February 10, 2007 So what do they sound like? Do you have the JBL driver hooked to them now? Quote Link to comment Share on other sites More sharing options...
ajsons Posted February 10, 2007 Share Posted February 10, 2007 here you go, jc, based from table 1, edgar's article. Quote Link to comment Share on other sites More sharing options...
jorjen Posted February 10, 2007 Author Share Posted February 10, 2007 If you add the thickness of the driver mounting plate, we arrive at 11.75" on my horns. I intended to use .75" stock for the mounting plate added to an 11" horn. The article specifies that once the horn is complete, cut off the throat end of the horn by the thickness of the driver mounting plate you have chosen. As stated previously, close enough I suppose. Quote Link to comment Share on other sites More sharing options...
jwc Posted February 10, 2007 Share Posted February 10, 2007 Absolutely. You easily see what I'm talking about. Now I cut flares calculated for a lower cutoff based exactly how he described it. I realized that with his technique, the bigger the horn...the more error there is w/o correction. For instance guys. My horn is 225 cutoff tractrix. Mouth 24" x 12". Horn length 17.5. Now I'm going to show you some images....this might further explain my point to others. This isn't to take away from Jorden thread as he doews beautiful work and I wondered what happened to his horn project. I'm glad he posted the technique. This image here is the jig. Notice that the height of the jig is 17.5 inches. It should be the length of the horn. The length of the top and bottom panels should be longer than 17.5. In my case, the length would be 18 3/16. IOW, the height of the trapeziod jib is 17.5 and the sides of the trapeziod is 18 3/16. What I did is correspond the exact measurement down the center of the horn to the corresponding measurement on the side of the trapeziod. So those horizontal lines every few centimeters is what the height of the horn should be that exact location measured at the side of the trapezoid. the measurement between the center and down the side is always different by a little. BUT, this will allow the EXACT area calculation at that point of the horn and then figure then calculate the width at those exact locations when drawing out the width at that location......the flares. Quote Link to comment Share on other sites More sharing options...
jwc Posted February 10, 2007 Share Posted February 10, 2007 Then here is the pic of doing the flare. The heigt of this cuyout will be 18 3/16.....not 17.5. this is because this Flare guide (top and bottom) of the horn will angle inward. Seen on next post. Quote Link to comment Share on other sites More sharing options...
jwc Posted February 10, 2007 Share Posted February 10, 2007 Sorry. Have to look close to see all the flared dots. Now in this image, is those flare cutouts...top and bottom standing straight up. Yes...they are 18 3/16 tall. They are seperated by 12"...the height of the mouth. Quote Link to comment Share on other sites More sharing options...
jwc Posted February 10, 2007 Share Posted February 10, 2007 Now when we angle them inward so that the tops are 2" apart (throat), the length of the horn is 17.5 inches from the mouth to the throat. Now you never can tell what you can do with an old 2.5mHy inductor laying around can you. jc Quote Link to comment Share on other sites More sharing options...
jwc Posted February 10, 2007 Share Posted February 10, 2007 Now I can never get them to look as good as your build. I hope to get some crudely put together to run some curves. Quote Link to comment Share on other sites More sharing options...
ajsons Posted February 10, 2007 Share Posted February 10, 2007 Jordan, I can't find where it says to cut off the mouth by the thickness of the mounting plate. On page 13, though, it says "Cut off the neck by the thickness of your mounting plate". Quote Link to comment Share on other sites More sharing options...
ajsons Posted February 10, 2007 Share Posted February 10, 2007 Yep, you're on the right track, jc. Good luck. Quote Link to comment Share on other sites More sharing options...
jorjen Posted February 10, 2007 Author Share Posted February 10, 2007 Lookin' good JC, lookin' good. As I stated previously, the thickness of the driver mounting plate you decide on, will come off the throat end of the horn prior to mounting the driver plate. I do not have the JBL 2482's yet. Jammin' Jersey has a pair. Supposed to be in great shape with the original Phenolics in them. $700.00 for the pair is slowing my progress just a bit. [] Quote Link to comment Share on other sites More sharing options...
jorjen Posted February 10, 2007 Author Share Posted February 10, 2007 Ajsons.....Oops[:$], I edited my post to read "Throat". Did not realize I typed "Mouth" until you pointed it out. Thanks. Quote Link to comment Share on other sites More sharing options...
jwc Posted February 10, 2007 Share Posted February 10, 2007 Where do you plan to cross the JBL mid......how low...and with what? My initial plan was to cross possibly down to 300Hz with the BMS driver. The Khorn clans out there may like something like that. jc Quote Link to comment Share on other sites More sharing options...
ajsons Posted February 10, 2007 Share Posted February 10, 2007 Its better to make that mistake in typing and not during construction. Cut and paste will be much harder.[] Quote Link to comment Share on other sites More sharing options...
jorjen Posted February 10, 2007 Author Share Posted February 10, 2007 You are absolutely right about that ajsons. JC, I have been thinking something along the lines of 500/5000 or so with the 2482/2404H. But, that was with the CornScala project and not a bass horn. I have not gotten that far yet. I will either have to design and build something myself or have someone else do it. I have to settle on the bass bin I am going to build first. I am leaning toward the Jubilee, but I am still very interested in Dana's V2 and one of his other designs. I have been on the fence regarding my bass horn for almost a year now. I need to make up my fricken mind and start makin' sawdust. Or, keep lookin' out for a couple Khorn bins to show up somewhere. But, that is'nt as much fun obviously. Quote Link to comment Share on other sites More sharing options...
ajsons Posted February 10, 2007 Share Posted February 10, 2007 jc, I sent you a p.m. Quote Link to comment Share on other sites More sharing options...
jorjen Posted February 10, 2007 Author Share Posted February 10, 2007 I sent you one as well JC. Quote Link to comment Share on other sites More sharing options...
oscarsear Posted February 10, 2007 Share Posted February 10, 2007 Jealous is the word. JC knows my interest here. He sent me the templates for his horns and I'm drooling to figure out how to turn them into a reality. I have the 2482's already, 3 of them in fact as I run a center mono channel that also employs one. Looks like I'm in line for some shoulder surgery in the short run so I'll have to keep on drooling. BTW I got 2 of my 2482's from Jammin Jersey. I got the 3rd on ebay. They're pricey at JJ and they don't do credit cards. The 2482 does seem to come on ebay regularly and Jammin Jersey now carries new phenolic diaphragms for them at $150 each. So you might get them at auction blown then rework them and be certain they're tops. Quote Link to comment Share on other sites More sharing options...
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