Hello experts, Jarjar here. Misa confused about Subs causing rumble on the stage. I worked as stage hand to a concert last week. They had problems with this rumbling movement caused by the subs. The subs were positioned in front of the stage, piled in 6 pairs, so there were 12 subs in total. But the vibration the subs caused was annoying for the musicians on stage. So, the techs decided to line up the subs instead of putting one of top of another. They took out their calculators and figured that if they put one sub 1mt in front of another the sound would phase up. Also, they said, it would take care of the rumbling on stage. But it didnt do much. ¿How would you solve this vibration if ceiling suspension is not an option? BTW, it was an outdoor festival with at least several thousand people in it.