Foam Core Board Speaker Enclosures?

Next idea is along the lines of daisy but as a Pentagon. Quick sketch is easy, real drawing, well, we'll see.
 

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OK, more to scale, I found this may or may not work. For the expansion needed, the 'petals' have to be wider like in this diagram so I'm not sure how the mouth flare is going to work. The actual change in the angles with be rounded not sharp as drawn but that seems to change rather quickly right at the mouth. As far as size goes, it's scalable like the other designs but I notice this has a much larger chamber and shorter horn lentghs. They seem to be about half of what the spiral offers. Right now the throat atarts at 1" and exits into the mouth horn at around 2.5" (pentagon - 32" flat to tip.)

Thoughts?
 

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Where in that huge thread....

Details of Flatter is Better BIB build in the Terry Cain BIB thread. I thought since it is a foam core build, better to post final pix and sound clip here though.

They sound great and have the ability to fill the room with some nice bass. I like how they ended up looking too. I just need to decorate them now.

Where in that huge thread did you find the plans for this little beast? Looks interesting.

I dug around a little but that thread is almost as long as this one is. :)
 
Founder of XSA-Labs
Joined 2012
Paid Member
Recurve,
I was initially inspired by Jhutka's TC9FD BIB
322415d1357667795-terry-cains-bib-why-does-work-does-anyone-have-those-fostex-craft-handbooks-bib-vifa.jpg

but wanted to make it flat for a wall mount as I have no floor space.

I came up with the flattened design based on the volume and length dimensions produced by GM's BIB calculator (which gives same dimensions as Jhutka's design above). I basically preserved cross sectional area by squashing the BIB to 3 in deep. I had to make an inverted V divider to have enough room for driver. Plan as built is below (note typo - 3 in deep not 4 in). I made the V curved as a change from original BIB design to buy more clearance for driver and hoping to make horn expansion exponential instead of conical. Very easy to do with foam.

326725d1359323897-terry-cains-bib-why-does-work-does-anyone-have-those-fostex-craft-handbooks-fib-asbuilt743522927.jpg

The thread is here: http://www.diyaudio.com/forums/full-range/66173-terry-cains-bib-why-does-work-does-anyone-have-those-fostex-craft-handbooks-516.html

Internals look like this:
326458d1359206536-terry-cains-bib-why-does-work-does-anyone-have-those-fostex-craft-handbooks-fib-01.jpg


I have mounted them upstairs (out of the "speaker warehouse") and have been listening to them a lot. They sound very nice - some people would say bass-centric but I like the sound for some types of music. It can actually handle rap and hip hop now - surprising :). I recommend it as a fun and nice looking speaker that fits into any room with no floor space.

X
 
Surface Tension,
Those look great, :cheers: so you opted for some pretty thick plywood there. It must give it a substantial feeling and less resonance on the baffle. Are those Vifa's being driven by the tube amp in the picture? What depth are you using on the channels?
X

Thanks xrk, I like the thick baffle for driver mounting, foam works well for the back and spiral. Thick baffle still seems to retain that magic sound on acoustic and vocal. Speakers are about 6.5' apart on center. The back has a piece of Sonic Barrier 3/4" foam 8"x 8" centered behind the driver with a ply strip 18"W x3"H x1/2"D (Gorilla Glued) and a saw tooth hanger. That makes the the speaker 3/4" out from the wall. Moderate stuffing in the channels, heavier stuffing at the exits. Sounds great as a stand alone system, integrates well with sub (PE SUB-1200) on demanding music (this room is big with high ceiling). The amp is Elekit TU 879S with JAN 12AT7WC & stock 6L6GC.

20"x20" with 2 1/2" depth channels

Sorry, no test data here, just ears and lots of :)
 
Founder of XSA-Labs
Joined 2012
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How are they for near-field?

I made my first 20in cornu this weekend and I see what you all mean by you have to stay back a bit...

They work well closer than cornu. Near field ? I listen to them about 7 ft away if that is near field. The bass goes up the wall and off ceiling so there are certain locations were room modes reinforce bass. Depends on room.
 
what are you making?
It's my 6 years old son that is building houses to his cuddly toys.
No speakers yet...
But hi is always making drawings first than cutting and gluing.
We use Pattex Wood Express glue.

This is the final house, I think it looks like the drawing.
No not really done, still missing lights.
NrA5ygL.jpg



2UyC98T.jpg


Sorry for the off-topic, but I will try to steal some foam board and build some speakers.
2-way BiB with Aura NS3 and a tweeter from the "speaker" bin.

\M