wiring uk mains (240v) to a car subwoofer.

bought a new mutant subwoofer (the 250w version) and didn't realise it was for a car. now i'm trying to wire mains through it. i have a 75w amp, but the sub is active, so only needs audio not power through the same cables. i think i might try and use an inverter, but i don't know the ampage it would produce, or how the speaker would handle it. any ideas? tl;dr new car sub, wire it to mains please?

i've looked into that, but its got a strange connection, like a 5 part power lead, with ends that connect to the battery. other speakers are mostly out of my price range, and the ones that are don't go as low. besides, it's a challenge.