I recently purchased an older 4647 cabinet that is cut for a single 15-inch woofer, typically a 2225, but in my case, it has a 2226J. I turned the cabinet upside down and cut a hole for a 2370 horn and a 2426J. I am satisfied with most of the sound, with the exception of the bass. It is lacking and muddy. My woofer tester says the 2226J has an Fs of 50 Hz and a Qts of .4. Cabinet volume is now about 4.75 cubic feet. My pencil and paper calculations suggest a port length of 1.5 inches for each of the four three-inch ports. I tried this, and it did not help. I have pushed the cabinet tight against the wall, which helped a little. I have tried different chokes--from a cored 14 gauge with a dcr of .16, up to an air-core 18 gauge, the latter sounding about the best overall. I have tried varying the amounts of cabinet (fiberglass) stuffing. More sounds better, but not good. I have tried different port lengths and numbers, resulting in minimal differences. I have a hefty amplifier, and I am using 10 gauge wire. I have an LR2 to the woofer at 1200Hz and 18 dB/octave up top (for what it's worth, I have found the Mundorf Supreme caps to be the best yet with the 2426J after many long nights of listening comparisons). The cabinet sounds misaligned, and right now, I am out of ideas and a little frustrated. The cabinet measures 30.5 X 20.5 X 17.5 externally. If someone has a comment or a suggestion, I'd love to hear it!