The "eye" layer is printed. It did not warp. I used Hilbert curve infill and that might have some influence as well - the rectilinear pattern shrinks in the two major direction lifting the corners. I got the side edges slightly concave, which does not matter at all.
I see a little design issue - there should be more screw holes around, at least a pair in the middle of the long side.
I see a little design issue - there should be more screw holes around, at least a pair in the middle of the long side.
Attachments
So here is are the STLs - the cone and joint are meant to be glued to the eye plate. The coverage angle is calculated as ca 51 degrees by Patrick Bateman's Paraline calculator. It is an easy print and with 0.2 mm layer it came out really nicely. I would like to try a "synergized" paraline - maybe it will even fit this one - only a new driver plate would have to be printed. The slot and eye plates will be glued together, but the driver plate needs to stay removable anyway.
Pelanj,
Nice prints!
From an eyeball inspection of the "eye", looks narrower than 51 degrees vertical dispersion to me. Do you have a link to Patrick Bateman's Paraline calculator ?
Art
Art, I found it here: ~ Sunshine ~ - it should have the correct A and D dimensions, but I used a three point circle through these, so it is not a true parabola as it should be if I am correct.
Freddi, this information should be sufficient for the printing service. The resulting wall thickness is (with my 0.4 mm nozzle) 1.2 mm horizontally and 0.6 mm vertically with the infill inbetween. If I remember correctly, the mounting plate is 5 mm thick in total and the tube walls 3 mm in total. If you specify 3 layer wall thickness, you should be fine.
Freddi, this information should be sufficient for the printing service. The resulting wall thickness is (with my 0.4 mm nozzle) 1.2 mm horizontally and 0.6 mm vertically with the infill inbetween. If I remember correctly, the mounting plate is 5 mm thick in total and the tube walls 3 mm in total. If you specify 3 layer wall thickness, you should be fine.
You mean coupling two 2" exit drivers together with two paralines above each other? If you define the thickness, A1 and D1 and mounting pattern, I can make a 3D model quite fast - in the same style as the small one. I guess it will be pretty large and it would need external support made out of wood to hold the weight of the drivers. And if you make a hand drawn sketch, it would be even easier.
Have you try any tube with a dome tweeter such as Tymphany ne19? What do you think about it ?
hey pelanj, maybe make a mid/tweeter module with 8pe21 and compression driver on the dual slot K-tube. If 8pe21 has enough on-axis rise then maybe a JBL style lens
rough pattern: https://i.imgur.com/E3MneZr.jpg
1hiep0 - K-tubes have been used with car coax such as 5 inch and 6.25" Polk with center mounted dome tweeters in Karlson style klams.
https://i.imgur.com/OiXOmeU.jpg
https://i.imgur.com/ecoPQ0b.jpg
This interesting oddball has a short K-tube https://i.imgur.com/6nWYJgm.jpg
rough pattern: https://i.imgur.com/E3MneZr.jpg
1hiep0 - K-tubes have been used with car coax such as 5 inch and 6.25" Polk with center mounted dome tweeters in Karlson style klams.
https://i.imgur.com/OiXOmeU.jpg
https://i.imgur.com/ecoPQ0b.jpg
This interesting oddball has a short K-tube https://i.imgur.com/6nWYJgm.jpg
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I am not sure if I got the paraline right. I checked the 3 point circle vs a parabola and for these dimensions, the circle is close enough with very minor differences. But the mouth should have been 5 mm wider, now I think I finally understand the spreadsheet. The picture compares the FR in my quick-and-dirty in-room style measurement the same driver (Beyma CP385Nd) in a small eliptical exponential horn (blue) and the paraline. There are some dips at 2.6, 3.7, 6.0 and 7.4 kHz that can be seen as negative group delay in the GD curve. I wonder if one could get rid of these somehow, I am going to try to fill the area below the driver plate by polyfil and compare.
