Foam Core Board Speaker Enclosures?

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If you made the mini Cornucopya from foam core facers you will have several 10 x 20 inch remnants. What to do with them? I have been meaning to make a little stereo mp3 player unit and plan to use some cheap pc speakers and amplifier but wanted a transmission line to boost the bass output. Based on remnants that I had, I came up with an A-frame shaped enclosure. There are two TL's each 40 in long (or 1 m), which gives a tuning freq of 85 Hz. The TL will be a little odd in that due to how it is folded using triangular divider channels, the cross sectional area contracts, expands, contracts, and expands before exiting at the front facing terminus. There is no real design here with regards to optimizing the TL as it was based purely on whatever I have left over in foam core remnants. However, I will place the driver at the 1/3 distance from the closed end. The speakers I will be using are the $6.99 specials from Microcenter ('Inland' brand http://www.microcenter.com/product/220684/Pro_Sound_2000_Stereo_Speakers) which claim to have a 3.6 watts per channel amp and oblong shaped 2 in x 3.5 in fullrange drivers. Here is what I managed to build in 1 hour this morning. Now I need to find some time to dismantle the speakers to strip out drivers and amp. I plan to mount the amp internally so that the whole thing will be self contained. I actually like how the design came out, it looks clean and modern, and because it is triangular, very stiff and needed no bracing. The tilt on the front baffle allows the driver to aim up a little bit which is good for a tabletop speaker. Oh, one more thing.... Now that I know how to record decent sound clips, I plan on recording a test track with original speakers as is from factory at same setting and distance. Then I will record the same with the new design and we will hear if the TL box improves the sound?
 

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Those speakers from Microcenter are really bad once I took them apart. The drivers are cheesy with no real foam surround just pleated self paper from the cone, and the amp is already giving intermittent sound now that I pulled it out, bad pot on vol knob, and the chip is a TEA2035b which only 2.3 w into 4 ohms at 9 v power supply according to spec sheet. So the 3.6 w rating was a lie - what do you expect from bottom of the barrel speakers? I am just so disappointed in these compared to Logitech s120's which are only a few dollars more. I am rethinking what to put in this cabinet now that I like the shape so much.
 

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That latex caulking could work but takes long to dry. Try Gorilla glue. I used hot melt to tack and white pva glue to bond. I think so far the glues used include: hot melt, pva (white and yellow), gorilla glue, liquid nails.
The biggest roadblock is getting the channels cut. Use a razor and straight edge - makes nice clean straight cuts. Once you have that and the design drawn on the board it goes very fast. The slowest step is the final bond of the cap. If use pva, takes overnight and with gorilla glue takes 20 minutes, or if you are sporty, hot melt the top in pieces.
 
I'm thinking I will use 2 panels for the front, I plan on doing some vinyl overlay on the fronts, so the seam won't be an issue.


Although....4x8 clear chloroplast is easy to get. If someone wanted that frosted look, you could use it for the front and backs and use the channels to route the wires in a clean way. Adhesive concerns would need to be figured out, as we have foam core, paper edges, and chloroplast to adhere. Not to mention one would have to be really good with the cleanliness of the glue and the edge cuts. I'm thinking ultra clear sealant (cant remember the name, comes only in a very clear sqeeze tube)
 
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How about acrylic latex bathroom adhesive?
You could just tack the foam board in place with hot glue and then fill the gaps with caulk I suppose.
You need the inherent tacky quality of the hot glue to hold the spiral in place as you are forming it.
Yes, that's what makes this project workable. I used nothing but hot glue on phase 1 of the spiral but I had to keep telling myself not to tool it like caulk.

The skin has almost grown back on my finger.