Lobbing -- def'n : An acoustic effect caused by multiple drivers sharing a horizontal axis, characterized by variations in perceived sound level as the listener moves about the room; resulting in the disgruntled listener tossing the offending speaker into the trash...

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8