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Best cabinet for odd subwoofer driver

Sir.Byrd said:
Okay, I can just use a tube, I was just being cheap :P
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PVC and cardboard tubes are both pretty cheap :scratch2:, but you seem to be pretty good with the woodworking - I bet you can figure out a way to keep that one piece of wood replaceable until post-testing. It's not that touchy, after all; you can just seal the seams with duct tape or something until it's time for glue.
 
I could have it be replaceable pretty easily actually, just put a few screws into it, might have to beef it up since it would be going into the edge of plywood, or I could make it out of solid wood or put in threaded inserts, or just get it right the first time.
 
Okay, could it be folded into four lengths? This gives what seems to be to be a better size box (as in, one dimension is not significantly larger than the rest)
The dimensions are not perfect, but they are pretty close. Cabinet thickness is 1" this time. Port tube is 5x5 with 3/8" wall thickness.
If this works, it won't be too tricky to do.
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Sir.Byrd said:
If this is wrong let me know.
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Looks good.

Pipe resonance theory isn’t based on swept volume per se, but CSA, so the slot would need to be of the same area as the pipe and due to the local boundary conditions would be much shorter for a given tuning.

A slot’s aspect ratio will affect tuning also, so depending on whose math you trust, the end correction could be so much that even just a baffle thickness cutout would still be too long, requiring a larger slot area.

GM
 
Sir.Byrd said:
Okay, could it be folded into four lengths?
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Sure! As long as you use the 1.0:1.414 ratio and the ~7.1 ft^3 net Vb is preserved, you can fold it up like a pretzel, with any response discontinuities being relatively minor and high up enough in BW that any will either be attenuated by internal damping and/or the XO.

GM
 
Would the port work along the side or top of the non-driver section? I was thinking that would give better placement options.
 
To maintain the same tuning, it just needs to be near the bottom. As it moves back up the pipe, it raises Fb [technically Fp], potentially creating a booming or even ‘one note’ in-room response, so the vent would need to be longer to get back to the original Fp.

Note that the driver’s specs and sim implies that the current ~20 Hz Fp is as low as practical [note the ‘saddle’ dip between Fl3, Fh3] short of stuffing the vent or sealing it up, so best to raise Fp by shortening it.

GM
 
Haven't built it yet.
Subway had a leak in their soda machine upstairs (and subsequently didn't know and/or care that it was a problem) and almost ruined everything in the back room.
Working my way too it, now it's waiting in the queue of actual projects, rather than potential projects.

Thanks for your help!
I will post photos when I get to it.
 
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