The bigger the drivers and the more you use means each individual driver moves only a little. Therefore the amp has a lot of control over the dampening. Hence better bass. I'm using 3 woofers because I'm monoing all the bass and using am only a single channel amp for the bass. Using 2 in parallel is a better load for the amp then 1 If your amp can handle it. NEVER WIRE SPEAKERS IN SERIES ! The impedance is screwier, if you need more impedance you can add non inductive resisters in series to the drivers. Anyway I've made my own with 3 18 inch drivers, the bass is perfect for the mmg's. Here's how to do it, the easy way instead of the way I built it. All the braces are 8 inch wide plywood, screwed and glued on edge to the panel and all braces are on the same side of the panel. After the first one they have to be custom fitted to fit in between the others. You'll end up with a rectangle that's divided up into 12 sections, 3 across and 4 down. These sizes below will work for 12 or 15 inchdrivers. To my knowledge this is a very rare way to build a sub, I've never saw it done any where. Get the highest wattage rating you can get, with the lowest resonant frequency. the spl will be 2x a singlecone. my spl is 100 db and at 4 watts you can't stand to be in the room. Mine is a mono. You could blow the drivers if your system is "cranked" so watch it. The sound is the best bass I have ever heard next to live jamming, my brother-in-law is a drummer. The kick drums are very accurate. The crossover can start at 35 hz because of such extreme sensitivity to input. Mine need a 12 db per octave cross over. I'mstill experimenting with mine. The front of the panel is 1 foot away from the back wall, so you'll be using 4 square feet of floor space for it. Paint to taste. Acoustically the panel is 5 ft. 4 in. by 7ft. 4in. Like magneplaners "they just shouldn't work because of the front and back wave canceling each other", but they do work and well ! Enjoy. 1. Get 1/2 particle board panel 4 by 6 foot. 2. Get 1/2 plywood boards cut 8 foot long by 8 inches wide. 3. Cut the holes for the drivers, one above center ( the 3 foot horizontal level ) by 3 inches the other 3 inches below. 4. Put 8 inch wide frame around the whole panel. Screw and glue it, going through the front of the panel in to the side of the plywood. The plywood will be edge on so that it makes the panel a shallow box. 5. Across the center of this boxed area, in between the holes cut and fit a cross piece from left to right side. This piece must be screwed and glued to the panel and at both ends to the edge frame. 6. Put in 2 vertical braces 1 inch away from driver holes, screw and glue it. Go from top to bottom. Also connect it to the center horizontal brace. God your having fun now! 7. At inches 20 from the top and bottom put in the last 2 horizontal braces. Again screw and glue the on edge plywood from thefront panel also connect it to the vertical braces. 8. With the speaker cabinet on its back. Silicon glue the drivers to the board, NO SCREWS. Trust me it works better and it will hold the drivers in fine. Let glue set for 24 hours. Its best to have the wires connected before you do this. Its also a good idea to just run wire straight from drive to amp, no jacks or plugs in-between Any questions, write me back. TAZSMONN Minneapolis