Volume of middle chamber?

I want to build this box, but I cannot find what volume the middle chamber should be. The subs are Rockford R1S4 12's and the MANUAL specs a sealed enclosure at 1.02 ft^3, if that helps.

I guess it's safe to assume that there is no specific answer after 120 views and 0 replies. Maybe someone has some guidelines? Should the middle chamber be the same volume as one of the sealed chambers? Or should it be the same volume as both sealed chambers combined? Maybe the middle chamber is nothing more than a ported common chamber box all its own?

Views can be from non-members and bots as well as members, so it's a meaningless statistic regarding answers. My suggestion is 1/3 of the total combined volume of the enclosed chambers. Keep in mind that you can easily make it smaller by adding material in the chamber, but it will be difficult to make it larger. Is there a particular reason you want to build this enclosure versus more traditional enclosures? the12volt • Support the12volt.com

My apologies concerning view count. After re-reading my previous, I can see how someone can infer a snarky tone, and that is certainly NOT the tone I wished to convey. Thank you for the explanation. I mistakenly thought that I might have stumped 120 people. In regards to the reasoning behind the design... I might have recently (3-4 yrs) discovered I have a touch of OCD. Primarily, it boils down to what I believe is the best balance between aesthetics and performance, without complete disregard for space utilization. I have a 2006 Acura TL and I currently have 2 12s in a 2.8 cu ft common chamber enclosure ported through the passthrough of the rear seats. 2.8ft was perfect for the four 8s I lost to an older (2000-ish) amp that finally bit the dust. I deconstructed the box and simply replaced the baffle board with cutouts for 2-12s instead of the 4-8s. Secondarily, I have been shown the light while lurking and researching. I am almost ashamed to admit that the current enclosure is most likely what caused the amp to fail. Hold your gasps til the end please: Single ply of 1/2 inch MDF throughout; no glue at joints or edges; held together with drywall screws; no bracing anywhere; not mechanically secured, carefully constructed to be wedged in place; poor fitment to the back of the seats; and finally, very little usable trunk space. If I were to build a 4th order box for a single 12, .66ft might sound about right. I will admit a little hesitation for that volume to accommodate 2 12s. However, the size of the rectangular port will be in the neighborhood of 4.5X10in or so. I will be removing the box that would get me fired, taking new and better measurements, and playing around with the calculators a little more to help with a plan of attack.