Frank was corrent in pointing out interconnect would be a better cable to substitute the stock REL cable. The signal cable in a REL sends low level info to REL, this is how REL detects how hard the main amp is working and at what freq range. Like power amp input, it's a high impedance input into REL and will not draw much current if any at all. For that fact, you want to keep the signal as pure as possible and shielding is more critical than current capability in this cable. Speaker cable does have shielding mechanism buildin, but not quite as extensive as interconnect in most cases.
Otherwise you will see the stock REL cable at least as thick as those Monster cable you can buy from Circuit City.