[QUOTE=3DSonics]PS, if in doubt, remember, the average kick drum is 24" in diameter and the skin gets displaced, depending on force applied via pedal and the tightness, both which contribute to the sound, by between a quarterinch to an in inch. I will leave it to the mathematcians in the crowd to wrok how many feet a 5" diameter diphragm has to be diplaced to match a 24" diaphragm displaced 1/3rd off center by 1".[/QUOTE] PPS, last time I enjoyed the Ravel instrumented verison of Mussorskies pictures they had 4 Kettle Drums on stage, each of them loosely tuned and around 32" diameter. Even accounting for room size differences, that is still major displacement. It does scare readily my 1" linear throw dual 12" subwoffer into a quivering heap of jelly. Arguably, I rarely listen to St Saen's #3 or the 'pictures', but is that because my system is too limited in the codpiece department or just because warhorses pease at times, but not all times..... L8er T