Down facing drivers

[evad]

This question has probably been asked and answered many times berfore, but the number and models of drivers change rapidly. "Are some drivers not meant for down facing? If so which, and what determines this"?
I'm interested in the PE 12" RSS315-4.

 

[myhrrhleine]

Floppyness of the cone.
Gravity pulls the cone down, out of alignment.
Thus it is no longer capable of equal +/- excursions and can distort.
VC misalignment with magnetic field also increases distortion.

 

[BoomieMCT]

This should answer all your questions about this.

 

[ashok]

Check this free download
http://www.subwoofer-builder.com/sonosub.htm

 

[evad]

Thank you Gentlemen, I was sure you would know the answer to my dilemma. In the driver specs the Xmax of 14mm is not noted as peak to peak, so I am assuming it is one way, If so the sag is approx. 3.36% which is within tolerances. By the way BoomieMCT, talk about an out of the way link! Thanks for the resource page.