Lucious Sullivan

Looking for assistance in finding an equivalent subwoofer to replace my 20 year old KSW 15. It's still working, but I experienced a crackling sound and it went out temporarily. I replaced the connecting cable from my audio system and it came back to life. Like I said, it's 20 years old and I need help finding an equivalent unit. It resides in a 20 by 20 room with high ceilings. Any help will be appreciated.