The making of: The Two Towers (a 25 driver Full Range line array)

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Are you looking for those numbers to do it in foam core? (lol)

I had not thought of it, but now that you say it... :) You can use -1 inch thick XPS foam sheets (home insulation sheathing) and cut with a hot wire preform (goes real quick). Glue and stack them up then cover with resin and fiberglass like a surfboard. There may be some ease of manufacturing and saving weight here - not to mention built in damping of internal walls. :D
 
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Yes X got it right, I have been an Inventor user for what seems forever. I'm an Engineer by trade but got involved in IT due to my interests in programs like Inventor and before that AutoCAD. I was always programming and streamlining the workflow. That's how I ended up in IT.
I have trained my coworkers in Inventor and was their walking encyclopedia :).

Here's a short animation made somewhere in 2005 for another hobby project of mine:

Apfelbeck Movie
render02.jpg

Click to see the picture properly. More on that project here: www.apfelbeck.nl
 
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Wesayso is pretty handy with the 3d modeling isn't he? I asked the same question - Autodesk Inventor. Similar results can be had with Solidworks.

I followed an electronics track during my studies and only got close to a drawing board for one semester -didn't do very well either. CAD is a foreign concept to me and I am only just starting to play with Draftsight.
 
Inventor isn't that hard to learn. Just need to learn the basics and play with it. I find it very useful for all my hobbies. I also used it for my car audio setup. Here's a waveguide design for a Vifa tweeter:
Ringradiator1.jpg


I made that pod to use the Vifa in my car and minimize diffraction. Worked very well. Actually, the great sound I got in my car is the reason I'm building new home speakers!
I printed the above model trough an online printing service.
xt25.jpg

DSP in my Pioneer radio takes care of the crossover and time alignment. The speakers disappear completely leaving you with a great stage that extends beyond the actual car boundaries. It sounds bigger than it is. I hope to achieve that in my living room as well :).

But I had Inventor running at home due to my job. It is way to expensive for a home user. If I ever start a business of my own I won't hesitate to buy a license.
 
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Back on track...

The two towers standing on their own. Still a lot of sanding to do on both towers but it's starting to look like something real.
2-Towers.jpg

Another feature visible in this picture is that I left the ability to rotate the speaker in any direction wanted. The speaker is almost turned 180 degrees :).
That should help with toe in/out experiments.
In some more detail:
rotating.jpg

(don't mind the missing bolts on the base, they're there ;))
 
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I'm going for nude plywood with stain covered with clear polyurethane. Plywood is hard to stain though. Takes some effort, hope my tests have shown me how to do it right.

That rotational base is water yet cut from my drawings, so I guess that makes it custom design. I wanted to be able to play with positioning without rotating the feet. It's not equipped for changes on the fly with the bolts facing downward but I'll manage.
 
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I'm going for nude plywood with stain covered with clear polyurethane. Plywood is hard to stain though. Takes some effort, hope my tests have shown me how to do it right.

That rotational base is water yet cut from my drawings, so I guess that makes it custom design. I wanted to be able to play with positioning without rotating the feet. It's not equipped for changes on the fly with the bolts facing downward but I'll manage.

Put a set screw on the side edge of the base to clamp a round disc mounted to speaker with large hole for disc in base. Then you can adjust on the fly. :)
 
I'm going for nude plywood with stain covered with clear polyurethane. Plywood is hard to stain though. Takes some effort, hope my tests have shown me how to do it right.

That rotational base is water yet cut from my drawings, so I guess that makes it custom design. I wanted to be able to play with positioning without rotating the feet. It's not equipped for changes on the fly with the bolts facing downward but I'll manage.

I am a huge fan of exposed plywood but it is difficult to get a good finish. Consider filling the ply with some kind of wood filler compound before sanding.

The other challenge is getting the burn marks out. I ended up using a dark stain on my TT plinth in order to hide the burns.
 
I am a huge fan of exposed plywood but it is difficult to get a good finish. Consider filling the ply with some kind of wood filler compound before sanding.

The other challenge is getting the burn marks out. I ended up using a dark stain on my TT plinth in order to hide the burns.

I had saved saw dust and wanted to mix that with wood glue to fill the pinholes etc. But I noticed on test pieces the glue would mess up the stain.
So I went with a dark wood filler :).
I'm going for a dark stain as well. The burn marks are all gone though after a week of sanding, pfew....
I do hope to get an even finish. My girlfriend wanted black speakers, they are supposed to be black she said. But I just couldn't do that after seeing how nice the ply looked. It will be a dark brown color, to go with our brasil brown oak floor. I hope to anodize the aluminum black. The feet will be left bare aluminum for now and polished.

The biggest challenge will be to clean the garage prior to paint. You don't want to know how much saw dust is everywhere. I'm considering building a tent from plastic for the paint job.
 
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