Designing a cabinet for Mark Audio Alpair 7.3

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Not yet. I have a shared workshop with all my tools being shared. One guy has a Cnc machine, he isn't so keen on sharing.... Need to work on that first as I have a stack load of projects that could be cnc'd.

Will post with progress. If you find my threads I've started the boom box like cabinet for my spare Alpair 10.3 will be my next endeavour. Then a bass cabinet for this and then horns and lots of them.
 
No doubt...

There is some good theory in their cabinet shapes, not to mention aesthetically pleasing.

What would you change if you had the chance?

Just to re-iterate, will be active with MiniDSP 2x8. Digital input via Mac Mini acting as music and movie server, with 8ch Rotel RMB 1048 power amp (40wpc)
 
What appears to be a very tight radius on the "back" side of the semi-elliptical shape might cause some issues trying for one piece with even the most flexible of bendy-ply - and Kerfcore type sheet goods have problems with really tight radii (the staves tend to telegraph through the top layer of plastic laminate or veneer).

If you never had opportunity to read the wonderful brochure that B&W put out at the introduction of the Nautilus series (which I've not been able to find on the web, yet), they form the bass enclosures from 2 pieces of custom curve laminated plywood splined in the middle of the back side - and of course with very elaborate matrix type bracing. The plywood consists of multiple layers of thin ( 3mm my guess) "baltic birch" ply, formed in hydraulic presses and CNC trimmed and routed with dadoes for the bracing skeleton and spline joinery.

All of such production machinery is beyond the budget of most DIYers, but jigs, vacuum bagging, "rubber" or bending veneer plywood and epoxy wood glues can do a pretty good job.
 
I had the joy of watching a rather thunderous movie, with loud music and battle scenes, and was forced to sit next to my little Alpairs watching them move back and forth was terrifying, and I kept turning it down to everyones annoyance. I hope this 'sub' will reduce some of the strain they must inevitably take.
 



that's the one - thanks


edit;

I thought that I remembered yet another brochure that showed the original 801 bass encloses fabricated in 2 separate "J" shaped panels splined at the rear. I either mis-remembered that, or they've since adopted a single piece fabrication technique, but as shown in the above documents, that's still rather above most DIYe'rs tool kit
 
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