Going to build a sub that can fit behind an acoustically transparent screen which has the ports either above or below the screen to minimize screen vibration.
turned me on to some neat programs that really help dial in the design and specs. I'm sure this is not the first time someone has built a sub to fit behind a screen with minimum depth and front porting above or below the screen a priority, but I couldn't locate any designs that fit my needs during my searches on this forum.
UPDATE - UPDATE - UPDATE
After all the suggestions, this is the sub I built. It's kinda of a cross between a Stonehenge and a Full Marty. Thanks to so many that post, share ideas and give suggestions. I hope this thread helps the next guy and gives ideas and confidence to anyone wanting to take on a DIY subwoofer project. From DIYsoundgroup.com's flat packs to custom designed subs, anything you set your mind to you can do.
Here's the specs on the sub (using a UXL-18)
~30" x 54" x 17.25" (18" with double front panel)
~13.63 internal Cubic Feet (12.43 Cubic Feet with bracing)
~46.99" Port Length
~Tuned to 15Hz
Total cost so far is:
UXL 18 = $550 (yep, I didn't get in on the group buy)
3 Sheets of 3/4" MDF = $96
If you pay someone to route these = $90
TOTAL = $736 per sub (not including the weeks spent on AVS dreaming and researching the design)
The interior sound deadening was another $30.
Cut out and ready to go....
Rounding the edges...
Test fit everything before gluing. It lined up better then I could have imagined. I expected to have to make some cuts, but it all was perfect and fit great.
Painted the inside of the port openings...
Rounded off the corners of the port and put a point on the port brace. Not sure it was needed, but since it was easy to do I thought why not....
It was a little scary at this pint. No going back... the glue is on!
Painting the port first is a great idea. Seen others do it and it works good.
Port corner getting a round piece of trim....
We put the egg crate foam on the places that would be hard to reach once it's done. We'll add more once it's fully dry so all walls will be covered.
Me next to the sub.
Clamped up and drying for the night. Took about 5 hours to put together with a friend helping me. This was our first time building a sub so I'm sure the next one could go faster.
17.25" wide. I'm going to add a double front so it will be exactly 18" deep when finished.