Wayne Parham Messages: 18789 Registered: January 2001
Illuminati (33rd Degree)
The illustration with the Linkwitz formula shows the forward axis is straight in front, but does mention hat it can be shifted by driver position front or back. It is also shifted by crossover phase. The two aren't the same kinds of delay, but if the overlap band is narrow enough, the effects will be pretty much the same. Crossover phase shifts delay by a moving amount proportional to frequency, but this movement is small if the overlap band is small. If the crossover uses low-order slopes, then the crosover band will be wide enough that the null angles will shift through the overlap band, effectively creating a wider null area.