https://www.google.com/search?ie=UTF-8&source=android-browser&q=truck+bed+liner+over+foam
(Third video down)
Bear with this guy till he stands on it, then I believe you will see the light.
Foam comes in sheets like plywood at Lowes etc.
. I had this idea for horn construction a few weeks ago and found this online today. IMO this makes everything much easier and it is waaaaaay inexpensive. I realize this may be moved to construction section but I believe it is important enough to stay here for a while as just about all of us are going to be making or buying Synergy horns sooner or later. In the aviation community we have been making airplanes something like this a long time, (albeit with a bit harder skin as your butt is in danger as opposed to a bad ear day) (-;
This is ideal for horns and perhaps could possibly be rendered non resonant enough for even enclosures in general especially small ones. There is a multitude of foam sheeting available at Lowe's etc. and trust me when I tell you as a Mississippian that pickup bed liner is STRONG and can cover rust holes up to a half an inch in diameter. Above is this fellows (very amusing) clip. Reminds me of "watch this sh** honey!" but ends well. (-:
(Third video down)
Bear with this guy till he stands on it, then I believe you will see the light.
Foam comes in sheets like plywood at Lowes etc.
. I had this idea for horn construction a few weeks ago and found this online today. IMO this makes everything much easier and it is waaaaaay inexpensive. I realize this may be moved to construction section but I believe it is important enough to stay here for a while as just about all of us are going to be making or buying Synergy horns sooner or later. In the aviation community we have been making airplanes something like this a long time, (albeit with a bit harder skin as your butt is in danger as opposed to a bad ear day) (-;
This is ideal for horns and perhaps could possibly be rendered non resonant enough for even enclosures in general especially small ones. There is a multitude of foam sheeting available at Lowe's etc. and trust me when I tell you as a Mississippian that pickup bed liner is STRONG and can cover rust holes up to a half an inch in diameter. Above is this fellows (very amusing) clip. Reminds me of "watch this sh** honey!" but ends well. (-:
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I followed your link and looked at the videos, and agree that it's got some promise. I didn't see a mention of a mold release agent, but it sure looks like you could develop a mold using the process that John Inlow describes:
DIY Paper Horn - The Paper Horn by Inlow Sound
but use the polymer instead of the paper-mache. Stiffen with expanding foam on the outside and you should be good.
Skip
DIY Paper Horn - The Paper Horn by Inlow Sound
but use the polymer instead of the paper-mache. Stiffen with expanding foam on the outside and you should be good.
Skip
Foam? Thefoam is just a core in a way. It could almost be dissolved after the liner is on, but that messes up the "stressed skin" thing we have going on. That liner is hard and thick. Really all we will be doing is vastly improving the jbl designs. Yes the famous 2380 etc are as anyone that ever dropped a speaker and broke the weaklings can tell you, just a thin plastic coat over dense foam, this is far far more rugged. Do not think of truck liner as "paint" think of it as eighth to quarter inch hard plastic. Really inert acoustically hardly rings when thumped. I think we are all working our butts off to make an inferior horn out of wood. Plus, instant prototyping and nearly pain free inexpensive revisions. it's working? Spray or brush on your horn. makes the throat adapter easy too, just bond it in and coat. Available in any color as well. You can slide refrigerators across that hard coating and it is very hard to break an eighth inch thick of dried spill piece in your hand. It expands slightly as it dries.
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Don't need a mold just a knife glue and a tape measure. The foam is the core, the liner is the strength. This is flat pack extraordinaire material, Would weigh next to nothing to ship.
Wood is a good material for horns. But even that can be improved with double walls sand filled. That's why my worry about rhino liner over foam. If something like sand between two walls of wood can make a difference, just how good is foam going to be?
I think it's a cool idea, just cautious about the materials.
I think it's a cool idea, just cautious about the materials.
Pretty damn good for mid horns almost certanly as it has already been done. But thinking further, nothing to stop you from gluing a thin plywood or other skin over it. Recording engineer intuition tells me that these layers would wind up pretty dead as acoustc resonators. There is a lot of data about light non resonant enclosures done by Harbeth, but again, these are horns, and foam horns sort of like this are already a JBL "fait accompli" (in redneck french) (-:
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One could concievably put a layer of quarter inch play around just the outside of the horn mouth wide enough to mount any woofers to. I really can't see any resonance here that would amount to much. Even doing that construction time and costs would be a small fraction of the weeks and month long process we have been using. A few hours instead possibly.These would obviously be flat sided as opposed to oval or circular Synergies, but hey those are working pretty good at Danley Sound. (-:
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Building Oblate Spheroid Waveguides Far and away the most difficult project I've done to date. Article By Jeff Poth
about halfway down- the biggest part of the horn, the mouth roundover, is foam covered in casting cloth, then fillers over top to make smooth. Casting cloth is a great material- improved if you mix in some woodglue into the water used with it, which gives it more toughness and plasticizes it. It still needs a coating but is tougher with the glue in the mix.
about halfway down- the biggest part of the horn, the mouth roundover, is foam covered in casting cloth, then fillers over top to make smooth. Casting cloth is a great material- improved if you mix in some woodglue into the water used with it, which gives it more toughness and plasticizes it. It still needs a coating but is tougher with the glue in the mix.
Good one. I was thinkng just buy a cheap horn of this type and cut the throat out. Really it all nust amounts to "no sharp corners or crap sticking out where the sound an hit it, just round everything over in the most graceful and slow and peaceful way" Hard to get a patent for common sense though, so we call it oblate spheroid around here. When we made horn throats in the early 70s we called it Bondo and common sense.
I'm going to go ahead and say this but I am sure everyone already knows this.. In order to get from a pipe such as the throat of a compression driver pretty much is, to the flare of a funnel, which a horn pretty much is, it needs to do ne so with no sharp bends that could cause diffraction which kinda creates another "speaker" or point source if you will, as gradually as possible. I'm certain that you could not br granted a patent, or make the gut at AES less likey to mess with or you certainly can't impress the great unwashed masses with this gem if wisdom, so handy words like oblate spheroid are needed instead of "make a radius instead of a sharp angle when you fix the speaker to the funnel. Ok that's out of the way....do that and it will measure and sound ideal when you make your horn out of pickup truck parts. Bwhaahhaa ( But seriously that's the whole deal).
Excuse me now I have to scratch my depleted solids exhalation aperture.
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