I drew heavily on Augerpro's carcass and port design. I made some modifications to make them fit behind my screen wall while allowing the L/R's to be able to accomodate up to 25 degrees toe in - crossing about 2 feet in front of the couch. I needed to rear mount the woofer to get the accoustic offset needed, so I build a box with a removable back. I also didn't follow his design entirely in that I didn't have the 1 1/4" huge roundover, and as an "econo" build, I was trying to not have to buy more tools (I already have a garage full!).
Final dimensions: 25.5" x 16.5" x 11.25". Baffle 1" thick (laminated 3/4" MDF and 1/4" MDF). Sides and back are 3/4" MDF. Final volume about 1.65 cuft net.
Components: Dayton PA310-8 woofers, Selenium D220ti tweeters, QSC waveguide, and Zilch designed e-wave SR crossover.
Here are two of the three glued up carcasses, with a 1/4" recess for the waveguide (the hardest part of the whole construction process).
Here's a closer shot of the recess.
I opted for a side mounted 4" port, like augerpro, and the best location ended up being a bit higher in my box due to the T shaped cross brace. Because of the removable back, an x shaped brace that went to the rear wasn't really an option.
The woofer hole is pushed right up against the WG opening, and I opted to use a 3/8" roundover on the woofer hole (right into the WG), edges of the box, and for the port roundover as well.
I put together my first crossover - breadboard, with the recommended components from Zilch's "flex your PCD muscle" thread over at the Parts express TechTalk forums. Not too hard really, even for me with no speaker building experience.
And here's the finished product!
The back, with recessed L-pad and terminals. On the inside, I added a 1.5" wide x 3/4" thick plywood keel right down the middle of the removable back to minimize flex in that large panel
The trio (two with left ports, one with right).
And in their final resting place behind the AT screen. The bottoms of the speakers are just above the bottom of the visible part of the screen, and the left and right are toed in about 25 degrees.
I'm still forming my listening impressions, but early listening shows them to have better midbass than the Infinities, and have much more detail to the sound. They are not as "in your face" as the Hereseys, but only have slight high frequency harshness at high volumes, where the Heresey's were unbeareable. So far, early on, they are hitting on all cylinders of what I need for new HT speakers. They can keep up (and exceed) my current sub on a very modest 100w receiver. I don't notice any compression even at listening levels well above what I would use (they get loud!!). I'm still dialing in the l-pad - currently at about the 12:30 position. It's nice that I can dial in the HF section to taste and how it responds in my room. As I add side wall diffusion/absorption treatments, I may have to tweak the pad - nice to have the option.
Thanks to everyone, especially Zilch for the component design, and Augerpro for inspiration on a really nice box/port form factor. These are not going anywhere, and I need to put my Infinities up for sale now.