Connecting a sub to a Marantz SR4200...help needed

[g-child]

Hi Guys,

I just bought a Velodyne vx-10 subwoofer for my Marantz sr4200 receiver. I was all excited on my drive back to the store (who wouldn't? it was Christmas all over again!)). However, the excitement was short lived. I connected the subwoofer (via the mono input) to the pre-amp subwoofer out on the receiver, enabled the subwoofer in the settings, popped in the loudest movie I own and...nothing! When I connect the sub to the front channel speaker, the cone moves, but not nearly producing as much bass as I expected. I suppose my lack of research has bit me in the butt. I've only read enough to decide on the model.

From my discription above, can someone diagnosis my problem and tell me how to fix it? I've never connected a subwoofer to my receiver, so I don't know if the problem is the receiver or the sub. I was also under the impression that the vx-10 has its own built in amplifier, however I am not so certain now. Do I need a special cable to make the connection (I using a spare RCA cable right now)? Any ideas or suggestions are welcomed. Thanks!