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Old 15th March 2013, 12:27 PM   #701
xrk971 is online now xrk971  United States
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Fran,
You have perfect English as far as I can see. Your plan for gluing seems good as long as you sand the channels so that they are all even and flat and contact the flat front/back pieces when gluing. I think Sebastian did the same thing and used heavy objects like a bookshelf with books to clamp the boards together while drying. I would use PVA woood glue. For the electrical wiring: with foam core, I just use a sharp tool to poke holes perpendicularly in the channels and run wire through. Note that you can use very thin wire for a full range driver like the FE108Sigma - in fact, many people recommend use of 24 gauge solid copper strands taken from inside a Cat5 networking cable. Two of those strands is enough and all you have to do is take a sharp razor and cut tiny little notches along the top edge of the channels to fit the wires in place. Then use hot melt glue to secure the wires in place on the notches and to make a good seal. Then when you glue to back panel on the wire will rest between the panel and the channel edge. Mount speaker cable binding posts (drill thru hole types) on the last channel wall and connect the wires to the inside terminal pins and you are done. Alternatively, Cal and others have just made a large cutout for a recessed cup type binding post holder for the wires right at the driver chamber (centrally located). Personally, I would go with the thin wires and notches to have binding posts on the bottom outside edge of channel so that the wires don't hang from the back of the speaker which allows it to mount flush against the wall.
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Old 15th March 2013, 03:01 PM   #702
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Hi X, I agree with you!
I'd prefer to have the binding posts located at the bottom of the speaker. I drilled a couple of holes for them on the middle plate, at the bottom of it , outside the spirals.

http://fperezroig.files.wordpress.co...pg?w=223&h=298

Thanks for the tip about the UTP cat5 cables and the notches!! That's definitely the way to go!! I'd have never thought that a couple of those thin cables would be a good idea. Why is it that you mentioned the specific fe108ez to be appropriate to use with thin wires?
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Old 15th March 2013, 03:14 PM   #703
xrk971 is online now xrk971  United States
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If you spend enough time on this forum you will see that people will recommend this setup for not only the FE108Sigma but all high efficiency full range drivers. First of all, the power requirements are rather low, and amps are not that high, and there are technical reasons like the added resistance is good for the damping factor, etc. Planet10 and others can give you the citation to the research behind this. Main reason I do it is thin and convenient and low cost. I have also used 4-solid conductor 22 awg in a white sheath for a stereo setup. That works well because the thin white sheath blends in well with walls. I sometimes double the 22 awg wire to get more current.
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Old 15th March 2013, 07:23 PM   #704
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Then without a doubt I'm using these wires. It's a great source of info this forum,still got everything to learn!
Thank you!
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Old 17th March 2013, 09:35 PM   #705
prezden is offline prezden  Canada
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Hi Guys- Happy Saint Patrick's Day
I lucked out a couple days ago and found a Bose SR-301 stereo for $3 at the thrift store. The drivers are destined for a new Cornu built. They are 2.5" (65mm) in diameter 4omh, 3W. I am guessing a size of 14" square by about 2" deep. Would that be the right size?
Here they are

Thanks for all your help!
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Old 17th March 2013, 09:45 PM   #706
xrk971 is online now xrk971  United States
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Prez,
Cool find! 16 in x 2.5 in may work better for 2.5 in driver. Not critical...
X
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Old 17th March 2013, 11:38 PM   #707
prezden is offline prezden  Canada
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Thanks X
I would like to keep them as small as possible. Would 14" be too small?
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Old 18th March 2013, 12:29 AM   #708
xrk971 is online now xrk971  United States
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Prez,
14 in is fine.
X
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Old 19th March 2013, 10:12 PM   #709
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Hey guys!

I just thought about a neat idea in the other foam core thread. Since vibrations appear to be one of the central issues of foam core, has anyone thought about damping vibrations with a liquid damper? You could possible apply it to the interior and exterior of the cornu.

DEI 050220 Boom Mat Spray-on : Amazon.com : Automotive

When I get around to making another set of cornu spiral horns, I will coat them with a spray like this. If anyone is making a set at the moment though, I encourage you to give this a try and report your findings! The main issue that we've discussed is that it might be petroleum-based and may dissolve the foam, although this spray appears to be mild.
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Old 20th March 2013, 01:05 AM   #710
xrk971 is online now xrk971  United States
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Give it a try and let us know. Another foam to try is the expanding insulation fill stuff.
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