I know this is old, but I have an old Aiwa stereo with dual casset decks, 5cd changer, aux ins, etc. and it's 200 watts and the speakers are bi-amped. One speaker cable has a blue RCA plug on it and the other is two bare wires. Is that similar to yours?
I would suggest finding a regular receiver for a home stereo system that is capable of running bi-amped speakers. Bi-amped means that the mid/high and low are powered by separate amps and that the frequency crossover is done inside the amp/receiver and not in the speaker. Then you can get a 1/8" to dual rca adapter and plug in that way.