Quote Originally Posted by stan View Post
great Ads!

13mm should be plenty, 18mm would be a very heavy cab, but may sound different...
i think open back is the way to go unless you like volume and porting calculations...

here is some advice from celestion themselves on making cabs - they dont seem to concerned over open back cab sizes...
http://celestion.com/speakerworld/gu...wn_Guitar_Cab/

I measured the thickness of the MDF used to make the Cab for my Marshall MA100C amp, and it comes out at 15mm, so yeah, I think you're right about 13mm being plenty.