My bedroom speakers. X-over design by Troels Gravesen can be found on his webpage under Vifa constructions. The first filter in the so called Vifa Premium 11 kit ( w= 2 mH serie + 10 uF (parallell) t= 3,3 ohm + 5,6 + 0,33 mH (parallell) was way to bright. The firts ten .. or so... cabinets had their flaws. This one is properly braced, flare ported and lined with bitumen sheets, felt on sidewalls. 1" eggcrate foam + 1 sheet of ½" sheepswool in the back.