Hello, new user here. I have 2 Eminence Kappa 3015's that I put in custom 1x15 LDS cabs that were built for JBL K140's, tuned to 40hz. Each cab is about 4.7 cu/ft with 2 ports originally 4" x 6". I extended the ports by 2", so now 4" x 8", but the speakers are farting out on the lower notes (4 string). Seems like these aren't ideal cabs for the Kappa's, but I thought I'd give it a try with my limited knowledge.
My other options are a narrow Acoustic 2x15 406 cab, and a JBL 4648 2x15, originally designed for subs in movie theatres (yes, it's heavy). I realize the latter seems like an obvious no-go but it's about 8 cu/ft with 2 ports 5.5" x 8".
So, are any of these cabs viable, or should I start from scratch? Is there an ideal cab dimension for these? Thanks.