You can purchase a couple of 8ohm resistors of the appropriate wattage to act as substitutes for speakers to run your cables in.
Keep the volume low so you do not exceed the wattage of the resistors and keep them well ventilated as they can get very hot. I normally place the resistors on side plates.
Keep the volume low so you do not exceed the wattage of the resistors and keep them well ventilated as they can get very hot. I normally place the resistors on side plates.