Tom Danley's B-DEAPE...

[qi]

Hi

Does anybody know how to build Tom Danley's (patent-pending) B-DEAPE?

Exactly what is going in inside?

Apparently it is two "mirrored" folded horns exiting in such a way as to exploit corner-loading.

There is a HUGE thread on it here...

http://www.avsforum.com/avs-vb/showt...hreadid=272320

[mikee12345]

its magic and ur not allowed to know

i dont know how a small mouthed horn like that can act proper mouthed in room.

thats for them to know,and for us to ... i dont know... NOT find out!

its the placement that counts.

my 25hz horn is 120cm x 90 x 45cm

(modeled and CADed)

[qi]

from the B-DEAP marketing blurp...

"The acoustic mirror image concept dictates that when an acoustic space is halved, the mouth area of a bass horn is also halved; when corner loaded, the mouth area is reduced to one-eighth. With the B-DEAP approach, the last half of the horn (the big end) is created through the existing room and enclosure boundaries."

...well, we know that much

[mikee12345]

That in itself is nothing new.my corner horn does this

However they have the acoustic space near the mouth restricted...

[John Sheerin]

Hi,
There's nothing magic there - just build a horn that matches the flair of the corner of a room when you position the horn a certain way in the corner. Pick the flair such that the room corner extension will allow you to chop off a majority of the horn, leaving only the small end to be built into a box. It would not be strictly necessary to use a dual path horn with 2 drivers - one would work if it had the correct parameters for a particular alignment. Other than that, it is typical horn design (ie, use 'real' formulas, not the dreck that floats around in unconnected forms on the internet). For example, try McBean's horn simulator, although that's not really a design program - just a method for evaluating a design.

Also of interest may be some FEA sims I did of a few different horn loading geometries in a corner.
http://ldsg.snippets.org/HORNS/basshornfea.html

John

[mikee12345]

Thanks john ive seen those FEA its good.And very easy to see results.

the mouth area looks very tiny for the bdeap it kinda gives u a fright

[Bose(o)]

Umm....it uses boundary gain to it's advantage?

[qi]

Also of interest may be some FEA sims I did of a few different horn loading geometries in a corner.

Hi John

Great job on those sims!

http://ldsg.snippets.org/HORNS/basshornfea.html

Have you had a chance to sim the dual B_DEAP setup they use in the home theatre link above?

They are firing two mirrored B-DEAPs toward the center of the rear wall about a foot off the wall.

As far as the inner design of the B-DEAP goes, do you think maybe that there are two mirrored folded (snail-shell) horns inside?

I believe I read somewhere that Danley described the inner design as "half of a LABhorn" (obviously the beginning half)

[John Sheerin]

Hi,
No, I haven't specifically simulated that geometry, but you can get an idea of what it might do based on what I have posted on that webpage. At low frequencies, it would work fine minus the effects of room modes - higher up it would start to have some directionality.

John

[qi]

This is my interpretation ONLY, based on other threads:

1. I cut Tom Danley's LABhorn plan in half diagonally.

2. I chose the half with the first half of the horn folding (DUH!)

3. I modified it for 1 driver only (needs much refinement).

4. I mirrored it and put the two halves together.

5. I resized it to be 42" x 42" x 18"...