Genesis Servo 12B subwoofer with Servo 12 amplifier

I recently came into possession of a Genesis Servo 12B subwoofer (#BC1386) and Servo 12 amplifier (#CC2571), inherited from the first owner. It's in excellent working condition, but I have no use for it. I am trying to find out more about it in order to determine a fair asking price but can find very little to no information on the internet. I'd appreciate any insights. Thank you!