Did you try any more rollback? I bet undulations between ~700Hz to perhaps 2kHz would smooth out. https://www.diyaudio.com/community/...-design-the-easy-way-ath4.338806/post-7082111
Only on this one: https://www.diyaudio.com/community/...-design-the-easy-way-ath4.338806/post-7081070
I don't like the looks.
I don't like the looks.
Oops missed that one, nice! and yeah the looks is not too nice... Response is sublime though. Undulations below 1kHz are due to another sound source who is >1/2ms late, diffraction. No idea how audible it is but past 1ms it potentially is, although small effect in frequency response. Anyway, just speculating, trying to agitate someone to say it is or not 
This type of waveguides interest me too for potentially easy manufacturing, at least hand tools suffice, perhaps cheap prototypes.
This type of waveguides interest me too for potentially easy manufacturing, at least hand tools suffice, perhaps cheap prototypes.
Good old stitch and glue, some filler and proto is ready Perhaps some plywood ribs to bend each side against, to make kind of exoskeleton for the waveguide. A plate to attach the driver (or throat adapter) could be screwed to the ribs/skeleton. All parts could be made easily with jigsaw. At least in imagination Perhaps cnc or laser cut for final version, I would imagine these are a lot cheaper to cut than 3D objects. Scissors would be the cheapest!
Perhaps some plywood ribs to bend each side against, to make kind of exoskeleton for the waveguide. A plate to attach the driver (or throat adapter) could be screwed to the ribs/skeleton. All parts could be made easily with jigsaw. At least in imagination Perhaps cnc or laser cut for final version, I would imagine these are a lot cheaper to cut than 3D objects. Scissors would be the cheapest!
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It seems easy to make at first but I'm still scratching my head how to actually do it
(including the adapter mounting, etc.)
Super easy.
If from flexiply or kerfed MDF, Just masking tape and PVA.
The card option is more work. I have some at work (1m square sheets at 1000gsm)
Laminating them would be very difficult to remove air gaps over an area that large.
For 6mm ply If the sides are cut accurately, you just tape them together and they will naturally form the correct shape.
I do it all the time at work. Same way violin fronts are attached.
The 3D printed throat would just slot over the end, or butt up to the rest of the horn.
I have 5 weeks left to make something if a suitable design is available in that window.
Of the many materials you can use, here is an example of acrylic. I've since made throats out of aircraft grade aluminium, to give strength where it is most wanted.
I was actually thinking if people wanted to do a cf group horn and then just print the throat adapter to fit their chosen device.I don't hope anyone here wants to make more than 100 copies of any design
I could help with that but I don’t want to step on any toes here and say there’s anything wrong with the folded layers approach. The uncomplicated surfaces on this device making folding possible also makes machining pretty simple. Just saying, and sorry for straying off.
I'm a carpenters son, so am happy to solve those parts.For example, right now I'm at a stage of calculating the right shapes of the boards. For accurate joints you have to cut them out bigger and then file off the edges, different angles at different places. It's really not so simple. Or maybe I'm just overcomplicating it.
Your are going for butt joints no? No angles to calculate.
To 45 degree bevel the joints would be extremely complicated yes.
Just add the wall thickness to the dimensions on the top and bottom piece only.
If you can get the profile of an appropriate horn as coodinates on a flat surface, I can do the rest, and in a way that anyone with a jigsaw could do no problem.
The corners can be reinforced with flush fitted screws going from the inside outwards to a brace if needed.
The throat section would need to be 3D printed though. I can draw this up and supply as a STL to fit a 1.5 inch exit 0 deg driver in a couple of hours.
Wood section would take 40 mins to make. I can video this so others can see how to do it.
The throat would be printed first, and used as a mold to 'hold' one end of the wooden section from the outside face only (otherwise it would protrude into the horn shape obviously)
You also have the option of adding any 3D printed profiles to the inside of the horn at a later date if if improves the response (aka 'klipsch mumps' or JBL 'diffraction lobes'. But I'm getting ahead of myself here.
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You're right, I didn't realize that with butt joints there are no variable angles - I took as granted that's not the case. My intuition fooled me again. That makes it considerably simpler than I anticipated!
Anyway, as I have already started with the calculations, I'm also going to prepare models for the miter joints...
Anyway, as I have already started with the calculations, I'm also going to prepare models for the miter joints...
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Minor correction:
The measurement will be ever so slightly out as the board is in tension.on the outside face and compression on the inside. This effect becomes worse as the wall is made thicker.
The effect is minimal though, and the center of the board is correct.
so I suggest the effect is ignored other than to cut the boards ever so slightly longer than the sim suggests (5mm would be enough).
It can then be sanded back level at the end.
Is this the problem you were thinking of when suggesting bevelling? In board that's less than 10mm thick, the effect isn't very large so I wouldn't worry. If you did want it correct it I can do this in Inventor, but I can't describe how easily in text:
The measurement will be ever so slightly out as the board is in tension.on the outside face and compression on the inside. This effect becomes worse as the wall is made thicker.
The effect is minimal though, and the center of the board is correct.
so I suggest the effect is ignored other than to cut the boards ever so slightly longer than the sim suggests (5mm would be enough).
It can then be sanded back level at the end.
Is this the problem you were thinking of when suggesting bevelling? In board that's less than 10mm thick, the effect isn't very large so I wouldn't worry. If you did want it correct it I can do this in Inventor, but I can't describe how easily in text:
People that are into fusion360, use the sheet metal tool. You can extrude the curved profiles and then make fusion "unfold" them so you can get the actual flat dimensions. There are tutorials on youtube.
I would guess that it's complicated to do by hand as the dimensions will stretch along the curve.
I would guess that it's complicated to do by hand as the dimensions will stretch along the curve.