do you need a gasket to invert subs?

[pwr2max]

I am wondering if i need a a gasket or mdf ring between the sub and enclosure if i am going to invert it? Also, do i have to worry about the rubber surround hitting the edges of the box if i follow the manufacturer's reccomended cut-out diameter (i am mounting the subs invertedly to the outside of the box)? thanks.

[InhumanAcura]

Wire them the opposite (reverse phase), use the recommended cut-out, and the rubber ring around the driver should be enough gasket.

[pwr2max]

lol that was short...thanks alot