I've got this old 1980 Carvin 15" bass master cabinet that I'd like to swap in a good (light) full-range efficient speaker, for a stand-alone practice/smll gig setup. Mostly classic rock/old school stuff, but I'd like something punchy enough for occasional modern rock numbers. The cab's net internal volume is just over 3 cf (with typical speaker volume subtracted), so I thought a Kappalite 3015 would be a good fit. I might have to add another port, the existing one is only 3" dia. Anyone try the Kappalite 3015 for standalone application, or have other speaker recommendations?