Big coaxial with RCF CX12N251

I was lucky to notice that #chriselm was selling a pair of FA253 amps here! And I got them, package will arrive in early April.

Today 4 hours at the worksop - front panels cut and stained, and spkA glued with Titebond and PU foam. Not seampless, but we have chemical wood...

spkA front panel PU.jpg
 
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celef - I did make several proto baffles! See posts 66-104! Making a proto of a complete box would be waste of time and material, it's so difficult!

krivium - The curved plywood leaves empty space that must be filled and contoured to make a "waveguide" In the proto I used cardboad sheets, but I decided to use PU foam and polyester filler putty. PU also kills resonances well and helps to keep the plywood curved (I hope :))
 
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You can also use grille cloth stretched int the shape of the baffle transitions and coat it with epoxy resin. Once cured you get a smooth solid surface that can be backfilled with fiberglass mat or PU foam. I've built horns with this method by copying the horn mold surface with grille cloth and cling film to protect the mold surface. Fleece blanket material can also be used for this and sets up even more solid.
 
https://www.biltema.fi/en-fi/car-ca...ywork-fillers/plastic-filler-054-l-2000040282
I have never used this filler before!
I might add plastic mosquito web... Biggest bubbles will be filled with crushed paper towels first! I'll do this later this week. The wedge will have straight profile, but depth varies, so I hope it will smoothen edge diffraction. Midrange is installed inside of the box, I'll try to make it's fitting as smooth as possible.



PU cut.jpg
 
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^What makes you think it would not sound good?

This is a hobby for me. I don't ask every speaker to be perfect, all my projects do sound a bit different despite of dsp, because they are different kind of constructions. Perhaps I will learn something... And there are hundreds of 12" coaxes and woofers, if I or my son will ever want to swap them. The RCF was on special discount!
 
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Foam is very soft and flexible. PE putty is rigid, but very thin near upper edge. The white stuff is normal water-soluble filler. They should take normal use and vibrations of a loudspeaker, we will see... Glassfiber web would have been too difficult for me.

NOTICE! I don't recommend this cabinet construction method to be copied!
 
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