"M10-A10" vs. "Silbury"

[cogitech]

Originally Posted by Scottmoose

He would. Back horns don't often sound like a regular box speaker; if he hasn't heard any & is considering these, I'd strongly advise he listens to a pair with a similar terminus configuration if possible (FH3 or something like that) & thinks long & hard before making a decision.

Perhaps this is something I need to learn before helping my friend with this decision.

I have never heard a back-loaded horn either.

Maybe I should do a FH3 build and stick a couple of my EL70s in them so we can both hear a horn before going forward...

[Scottmoose]

I would. If impractical, then you already know what I think, it just tends to underline it.

This is the open baffle thread: http://www.diyaudio.com/forums/full-...e-project.html

Excellent. Thanks Jim. Not sure how I missed that one.

Oh, they're doing fine. I finished the prototypes and they are the current speakers in my 2-ch.

Very neat.

[xrk971]

Originally Posted by cogitech

Perhaps this is something I need to learn before helping my friend with this decision.

I have never heard a back-loaded horn either.

Maybe I should do a FH3 build and stick a couple of my EL70s in them so we can both hear a horn before going forward...

Build it with foam core first to get a feel of the sound, super fast and doesn't cost anything if you have drivers already. I built an FH3-inspired horn and really like how it sounds. It has really helped to give me confidence to build it in wood later.



FH3-inspired Foam Core Mini Build

And if you don't like how it sounds, you have only lost a day of your labor. If you like how it sounds, like I did, you have a set of nice sounding speakers that you can use in places where you ordinarily would not take a heavy, expensive speaker.

Good luck with your decision.

X

[cogitech]

Very cool xrk! I saw that thread before but it is hard to believe foam core sounds good.

I might just do it.

In fact, maybe I will build Silburys out of foam core, just for sh!ts n' giggles!

[xrk971]

Foam core Silbury's would be a sight to see.

[cogitech]

Originally Posted by xrk971

Foam core Silbury's would be a sight to see.

Indeed.

I doubt they make 72" foam core panels, though. I'd have to laminate offset layers to achieve that length. This would increase cost, but it would provide extra strength and damping, too.

[xrk971]

Sorry for the thread hijack. If we continue with this line, we should take it up in the foam core thread.

For a quick and dirty foam core horn, you can butt-join the panels together with hot melt glue. The numerous channels on the inside provide a lot of supporting bracing underneath the panels so it will still be quite rigid. The exterior panels just need to be airtight and the hot melt glue joint does that very nicely. If you wanted, you can add a thin layer of paper on the outside of the butt joint with PVA glue and it will increase strength and rigidity and make it look like one big piece.

Uline sells bigger pieces of foam core (96 x 48 inches in fact but they want $15/sheet and you have to buy a carton so it is prohibitively expensive). 48 x 96" White Foamboard S-11755 - Uline

The Elmer's brand board which is really nice and perfect for exterior panels is available in 36 x 24 in size so that only 2 would have to be butt joined. But again, price may be prohibitive to buy a carton of 25. At least it is only about $4 ea or $100 a carton. But if you think about how many speaker projects you can make for the $100, it doesn't seem so bad... hmmm...
http://www.dickblick.com/items/13202-2020/