''Scoop design"

One other architect issue
I have a concept dinner ,ready made shop and for this deal the architect is the king ....
HIFI speakers are actually encapsulated in the design of the shop .
4*2Way 8"speakers enough for dinning, for about 100pax, but later on after the food there might be just a bit of dancing ....
so bass is not enough ....
King of the shop refuses to go for biger speakers ...
king of the shop refuses to install a couple of small subs
SO existing speaker is a Hifi speaker 2 way 100W in a sealed enclosure
Again the size of the box is given and the goal is to produce as much base is possible ( even if this might not be right soundwise )
I guess this is a story that we go for best bang
So there is one chance to go for a bass reflex design to gain more bass....

But i was offered one other design that i am sceptic about and i need opinions
The guy who calculated the box sent me a brief diagram and promissed to produce more bass than a typical bass reflex
can you comment on the idea ? ( later on i expcect dimension and choice of units )

scoop.jpg
 

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Excuse the graph is poor
hint here is that if one calculates given size, to given units , with a front bass reflex design there is a very good chance that the size of the box cannot accomodate the bass reflex tube ...Height of the enclosure might not enough for that ....
One option will be a double but smaller calculated reflex left and right of the tweeter,
other option will be to have oval bass reflexes again left and right of the tweeter Behringer style
and the last option is to do a port like the picture seen above or any other idea
 
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So it could be any of these designs or it could be a port Question is what will produce the most bass
At low volumes, given the same box tuning (Fb) all the ports will perform approximately the same in the low frequency, though proximity to the woofer will create different phase cancellation effects in the midrange frequencies.

The larger area, deeper rectangular shelf port depicted in the first post has more enclosed volume than the smaller ports depicted in post #3.The larger enclosed volume port will have a lower vent velocity, so will be able to be linear to a higher sound pressure level than the smaller ports.
At high volumes, the deeper shelf port will produce the most bass .

None of the above are "scoop designs", nicknamed because of the back loaded horn's resemblance to a sugar scoop:

Scoop Designs.png
 
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No the area that speaker is placed is a specific area and this cannot be changed
About 50 cm Height 28 cm wide and 23 cm deep
speakers are installed in a decorative construction and this cannot change
installing any other visible unit is not allowed
What I mean is: Are there any cavities in the ceiling/In the floor of the upper floor OR in the ornamentive construction. Such caveties can be used for bass.
 
No the area that speaker is placed is a specific area and this cannot be changed
About 50 cm Height 28 cm wide and 23 cm deep
speakers are installed in a decorative construction and this cannot change
installing any other visible unit is not allowed

50 cm x 28 x 23 (18 cm thickness) 21.96 litres or .78 cu ft


Ceiling Speakers, here's 3 examples
JBL 328c, Electro Voice Pro 8A, Focal IC 108 (nla)
https://jblpro.com/products/control-328c
spec sheet shows 1 cu ft box measurements

https://ojas.nyc/
https://ojas.nyc/collections/frontpage/products/artbook-shelf-speaker-hammertone-gray
16” h x 14” w x 12.5” d or Metric 40.6 cm H x 35.56 cm W x 31.75 cm D (18 cm thickness)33.29 litres



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Electro Voice Pro 8A
.26 cu ft to 1 cu ft sealed or vented

http://pdf.textfiles.com/manuals/STARINMANUALS/Bosch - EV/PRO-8A, PRO-8AT5, PRO-8AT30.pdf


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Focal IC 108 (nla)
https://www.focal.com/sites/www.focal.fr/files/shared/catalog/document/FT-IC108-gb.pdf

 
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