AzmodonAfter getting the diffuser on I needed a new project... with 8 days till the final races... and after seeing 514's build, and many many hours of youtube, I decided to give it a shot. Having never built an enclosure before, why not jump in the deep end with a 4th order band pass?
First Idea
needed more air volume above and below, but didn't want it to be taller, so I added air columns to the rear - the port on the right side is tuned to the resonant frequency of the sub.
converted to 3D for cutout patterns
laid out
cut out Monday night
Parts arrived last night at 6pm
Box 90% done by 3am
Tonight's wiring and final assembly + resin coating
(calculations for the nerds)
Sub requirement for ported = 1.1ft^3 minimum / sealed = 0.6ft^3 optimal
Resonant @ 38.4Hz
displacement = 0.07ft^3
Octagon volume at bottom = 2(1+2√) x 4.55in^2 x 2in = 0.11569ft^3
Lower chamber = 35x16x3 = 1680 / 1728(in^3 to ft^3 conversion) = 1.208ft^3
Expansion box = 6.25x13.875x2 = 173.4375/1728 = 0.1ft^3
supports = 0.003ft^3
Total = 1.423 - 0.07 - 0.003 = 1.35ft^3
Port size needed = 2 x 2.875 @38Hz = 5.97"
Port dimensions = 2 x 2.875 x 6" + chamfered edges
Sealed chamber = 35x14x1.75 = 857.5 / 1728 = 0.4962ft^3
Expansion box = 17.25 x 2 x 5.75 = 198.375 = 0.1148ft^3
expansion box entrance (volume of the cutout between the chamber and the expansion area) = 0.5x1.75x17.25 = 15.09375 = 0.0087ft^3
supports = 0.0008ft^3
Sub face displacement offset by dished area
0.4962 + .1148 + 0.0087 = 0.6197 - 0.0008 = ~0.62ft^3
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