So I found myself constantly looking at other cabinets, I found the BC410, and BC210 cabinets as O.K., but not an overwhelming good sound at loud volumes. So I took the cabinets apart to inspect the drivers and this is what I found, They didnt lie in the advertising of these cabinets, they are custom Eminence drivers. Just really low quality offshore Eminence drivers. I was curious of the specs on the drivers so I e-mailed Eminence and they emailed the specs below. Re 14.62 Ohms fs 58.7 Hz Le 1.06 mH Mms 21.5 grams QM 2.76 Mmd 17.7 grams QE 0.81 Cms 0.341 mm/N QT 0.62 Rms 2.877 N*sec/m Xmax 3.30 mm Vas 61.2 liters Pmax 75 Watts SD 355.4 cm^2 Bl 12.01 Tm VD 117.4 cm^3 Coil Diameter 1.50 Inches EBP 72.9 Gap Height 0.24 Inches Magnet Weight 20 ounces Efficiency 1.49 % Winding Width 0.500 inches SPL 93.7 dB 1W-1m On the plus side the cabinet itself is made of descent quality, with some bracing between the center supports. Comparison between the original drivers and th 4 Ohm MCM replacements I am going to use. Picture of all the drivers replaced, rewired the cabinet in series/parallel. Redid the 2X10 cabinet as well, below is a stacked picture of both. I havent had a chance to really crank these up, but so far a quick low volume test tells me this has made a significant impact on the bass authority and clarity. These have a great midrange as well, by far better than the stock drivers TC Electronics loaded these cabinets with.