ATH4 waveguide inspired multi way

bendy plywood + glass matt + resin. The above acts as form tool too.

Roughly speaking...
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I do wonder though… with know-how of, and access to, such manufacturing technologies, why bother with wood at all, especially as good quality ply has become quite expensive.

Earl Geddes used PU (sheets and cast), Magico uses reinforced carbon fibre plus CNC’ed aluminium baffles in their M-series, and YG simply makes everything out of aluminium for their higher end speakers. I haven’t heard Earl Geddes’ speakers, but the other two makers achieved a clarity in sound I have never heard from any speaker with a wood cabinet.
 
Gelcoat, glass matt, 1L resin. The 4mm thick baffle worked out at £70 plus an hour. I then bond in a machined 15mm ply in the back. It’s really quite a stiff inert baffle at that point.

In between the bendy ply i intend to add a glass matt. It will be a stiff curved cabinet.

Designing the way I have allows me to rest the cabinet on it side, throw in some chop strand glass and pour in a casting resin. Quite a few low shrinkage fast cast resins around now.

I guess the ultimate would be to use FEA and alter design to minimise resonances.
 
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I’ll see how glass reinforced 4 layer bendy ply does and get back to you. I could stir 10/20% stainless steel 30um powder (600g or so) into the resin used for the rear cabinet laminations. 😁

With CLD often what you have available can be used to good effect.
 
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Sorry for the slow progress reporting!

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The cabs are coming along.

4 layers of 5mm ply + 400g matt in between each layer. I’m going to use stainless steel powder in the intermediate layers to add some mass. Also, the polyester resin should infuse into the bendy ply to create an interesting plastic/wood composite in those layers.

All finished with 1mm wood veneer.

The new design front GRP baffles are almost done. Will update next week with those.
 
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I do wonder though… with know-how of, and access to, such manufacturing technologies, why bother with wood at all, especially as good quality ply has become quite expensive.

Earl Geddes used PU (sheets and cast), Magico uses reinforced carbon fibre plus CNC’ed aluminium baffles in their M-series, and YG simply makes everything out of aluminium for their higher end speakers. I haven’t heard Earl Geddes’ speakers, but the other two makers achieved a clarity in sound I have never heard from any speaker with a wood cabinet.

I still have a pair of Beovox CX 100 and a few Meridian DSP33 as surrounds. Both use cast or extrusion alloys for the bulk of the cabinet.

I’ve been using resin boards from Sikka and Trelleborg for 25 years in my day job. I have no hesitation to try anything. Part of me enjoys working with wood too though. Sadly I’m super busy so finishing hobby projects is super long process.