You will need two adapters (Line level or something similar IIRC) to take the speaker signal and convert it to the phono inputs that a normal amp would need.
Some amps can take a speaker level input.
I've found Steve at MegaWatt a very very helpful guy in the past.
Tel: 01928 500015
Email:
[email protected]
Give him a bell, I'm sure he'll be able to
help you out.
Cheers,
Steve