Like my decision to purchase a Dayton Titanic MKIII Subwoofer Kit, I also decided to simplify the crossover design by selecting an existing crossover that complemented the driver selection. Dayton's XO-2W-2.5K 2-way at 2,500 Hz is a second order 12 dB/octave crossover well suited to the SC-5.1 design, since the Hi-Vi M6N is relatively fl at up to 3,000 Hz and the Hi-Vi TN28 is good down to 2,000 Hz. Thanks to suggestions from Mike Van Den Broek and Brian Myers at Parts Express, I added a contour filter consisting of a 3.0 mH inductor paralleled with a 16 ohm non-inductive resistor, wired in series between the speaker input terminals and the Dayton crossover. They also recommended adding a conjugate fi lter consisting of an 8.2 uF capacitor in series with a 5.1 ohm non-inductive resistor, wired in parallel between the crossover and the woofer. And although the woofer is rated at a nominal 8 ohm impedance, they deduced that the best results are achieved by using the 4 ohm tap on the Dayton crossover.