This is the next step from the plastic horn I made as the very first prototype: https://www.diyaudio.com/community/...-neile-alo-horn-by-sphericalhorns-net.390581/
In this thread, I would like to show the workflow. I really enjoy watching other people's work, so I hope you will enjoy this thread as well. First, some overall data. The horn is ca 64 cm wide, 47 cm deep and 29 cm high. Each is made of 16 layers of 18 mm birch plywood and weights around 20 kg (estimate, did not weigh one). One horn needs two 1500 x 1500 mm sheets with a bit of leftovers. In total, the plywood bought was over 120 kg of material.
The workflow need to fit my hobby CNC. First, I cut all the single layers and rough the 3D parts. This was done by a 1/8" milling bit. Then, the layers are glued by two together and machined with the finishing pass with 6 mm bit. Glue up of the dual slices follows, during the project a friend of mine developed a unique press using water pressure to clamp the curved surfaces perfectly together. Then it is sanding, sanding and more sanding, gluing the two halves together, fitting the driver flange and more sanding.
Ready to start round one.
The slices are arranged to minimize waste.
Another layer cut.
Glue the two roughed layers together.
In this thread, I would like to show the workflow. I really enjoy watching other people's work, so I hope you will enjoy this thread as well. First, some overall data. The horn is ca 64 cm wide, 47 cm deep and 29 cm high. Each is made of 16 layers of 18 mm birch plywood and weights around 20 kg (estimate, did not weigh one). One horn needs two 1500 x 1500 mm sheets with a bit of leftovers. In total, the plywood bought was over 120 kg of material.
The workflow need to fit my hobby CNC. First, I cut all the single layers and rough the 3D parts. This was done by a 1/8" milling bit. Then, the layers are glued by two together and machined with the finishing pass with 6 mm bit. Glue up of the dual slices follows, during the project a friend of mine developed a unique press using water pressure to clamp the curved surfaces perfectly together. Then it is sanding, sanding and more sanding, gluing the two halves together, fitting the driver flange and more sanding.
Ready to start round one.
The slices are arranged to minimize waste.
Another layer cut.
Glue the two roughed layers together.
After CNC finishing pass, freely stacked to see the fit. Worked out really great.
CNC work is over, from now on, it is just a manual job.
Sanded haves glued together for even more sanding.
But before that, the monster press in action.
A detail of the flange. The horn profile is fully integral into the main body.
Some pictures before the final sanding session. Already looking great!
And the last picture, in action as a part of the system. My thanks go to @docali for designing such a great horn and having the opportunity to listen to them in a world class all analog system.
How do they sound? Awesome. All the other components of the system are top notch and the listening room is acoustically treated, which is a big part of the great sound, but in my opinion, there is nothing like a great large horn with perfectly controlled dispersion and absolutely zero resonances. And that is what WN300ALO is.
It is this one with brushless spindle upgrade: https://lupa-cnc.com/lupa-v-2-7-rozsirena/ Only in Czech, though.
...my choice was to apply a set of professional violin varnishes. Still not finished as the final treatment still needs to be done.
