Designing a cabinet for Mark Audio Alpair 7.3

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I know the software can slice up, and there is a plug in for sketchup to allow this. I have a detailed technical drawing showing each layer, but would be good for this process to be automated, and if I need to change the shape by a few mm here and there I don't have to re-program everything!

Being able to make natural organic shapes, will be a huge bonus to custom speaker building, And means I can create interesting and distinct speakers and shapes that would otherwise take numurous moulds, fibre glass and filling, like these:

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I've bought two pairs of Alpair 7.3s, one each for me and a friend. Having plonked one pair in Frugel Horns, I was looking around to figure out what to do with the other pair and thus went through this thread with some interest but am disappointed to note that climax is missing.

I'd be glad to see the outcome.
 
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I've bought two pairs of Alpair 7.3s, one each for me and a friend. Having plonked one pair in Frugel Horns, I was looking around to figure out what to do with the other pair and thus went through this thread with some interest but am disappointed to note that climax is missing.

I'd be glad to see the outcome.

Maybe a flat wall mount MLTL may be of interest?

http://www.diyaudio.com/forums/full-range/260758-full-range-wall-home-theater-11.html

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I wouldn't bother with the foam core unless you want a strange shape. I tried it, and in the end it wouldn't have been much harder to use plywood. I can cut wood cleaner than I can cut foam core too. If they sound good when you're done you'll want to make a permanent cabinet anyway. On my last project I bought foam core and ended up using plywood after the first cut didn't come out straight.
 
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I wouldn't bother with the foam core unless you want a strange shape. I tried it, and in the end it wouldn't have been much harder to use plywood. I can cut wood cleaner than I can cut foam core too. If they sound good when you're done you'll want to make a permanent cabinet anyway. On my last project I bought foam core and ended up using plywood after the first cut didn't come out straight.

Need to practice your technique. A straight edge and a break off tip utility knife can cut 30in long cuts within 0.5mm accuracy. Lay on carpet mark start and end widths with pencil. Align straight edge and cut first cut gently enough to pierce paper. Subsequent cuts press harder and 4 or 5 cuts it goes through. Foam core is definitely faster and cleaner for prototyping. I can build an entire synergy horn in one night. Try that with plywood.

Plywood has its place but foam core is faster and cheaper (in U.S.) some constructions require its flexibility for curves (Cornu wall mount horn).
 
I tried practicing the cuts, and never could get a clean one, even with a new blade. I agree that for prototyping it is convenient, but I'm building known boxes.

The other thing is foam core doesn't hold up to abuse by college students. I made one pair using FE126e in foam core for one twin, the other twin wanted a pair so I built Lances with FF85wk out of ply, now the first one wants "real" speakers. The wood is cut and just needs assembly. The Lance is an easy build because you just cut 4" strips from the sheet and then cut these to length. Chop chop chop and all straight and square.
 
Find someone local with a holzma beam saw (CNC saw) and you never have to worry about making speaker cabinets again. Absolute accuracy, nested to perfection, no burning or marking, no heavy lifting. I can just get a 18mm board onto our saw, wouldn't want to try with 24mm+, but in cut components its easy peasy.

@xrk971, not to go too far off topic, but how did you design, draw, cut your synergy horn?
 
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Find someone local with a holzma beam saw (CNC saw) and you never have to worry about making speaker cabinets again. Absolute accuracy, nested to perfection, no burning or marking, no heavy lifting. I can just get a 18mm board onto our saw, wouldn't want to try with 24mm+, but in cut components its easy peasy.

@xrk971, not to go too far off topic, but how did you design, draw, cut your synergy horn?

Design cut dimensions using Bwaslo's synergy spreadsheet - the Akabak to simulate response and iterate mechanical design. Cut by hand using a razor, straight edge and ruler to measure. Good point about CNC cutting of wood parts. There are also some cabinet builders available who charge a very reasonable price. For me though, there is a lot of satisfaction from making a new speaker so quickly and one I can move easily as it weighs nothing.
 
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