check the fuses in the marantz (if there are any)...

Bigger cables could raise capacitance, and lower resistance, though this is only a little difference, it could be a trigger for the amp to clip, at loud volumes, combined with low impedance. This could cause the amp to go in protection mode, possibly blow a fuse. worst case scenario it'll fry your amp, but this is in a really extreme situation...

Normally, though, a cable couldn't do this...

check for fuses in the nova too, could be the main fuse that blew...
as long as you haven't seen the magic blue smoke, it's still fixable


Keep them spinning,
Bert.