As Drubin says, the REL is designed to be connected to the speaker outputs of your amp.....i've owned a few Rowland pieces and have a Storm III and can't remember anything different about the speaker connectors...
if you were planning on using some Pre-Outs, don't, the REL sounds better at the speaker outputs.
if you were planning on using some Pre-Outs, don't, the REL sounds better at the speaker outputs.