Right, I mean there's a small amount of non-linear compression due to confining the pressure more on one side than the other, but it's negligible, and of course the larger FH for a given BW normally yields a lower distortion than a BH, but due to our falling hearing acuity with decreasing frequency and the increasing room affect on it, it's pretty much moot.Also, this doesn't mean that some ~FR drivers can't be compression loaded, just that its BW will be more HF limited than if not. FR drivers that have a peaking mids/HF roll off FR indicate a stiff/damped enough diaphragm to compression load for use as a wide BW midbass/mid FR.
GM