When it came time to design the crossovers for these speakers, I chose to shoot for fourth order acoustic slopes. Second order slopes would certainly be an option, but I often find that it takes less components to achieve a fourth order slope, especially with drivers that need a little extra attention in their breakup regions.

To achieve the fourth order acoustic slope on the woofer, I used what is essentially a second order electrical cutoff plus a notch filter. The notch fi lter is primarily used as the means of baffl e step compensation. Because of the nature of the baffle step, small speakers tend to suffer from a sharper transition from 2 pi to 4 pi space, and it occurs at a higher frequency. In my experience, using a notch filter in these situations can be more effective compared to conventional BSC filters.

The tweeter utilizes a simple third order electrical filter with a single resistor for attenuation. Together, the net crossover point between the woofer and tweeter is 2300 Hz.