Well, if both the Output and the Direct Out are hooked up to amps, the Output will only output the delayed signal and the Direct Out will output only the "dry" signal, or what you're actually playing.

If you plug a dummy cable in the Direct Out and feed the Output to your amp and set up the dials like I described above, then only the delayed signal will output to your amp. That makes it sound really interesting... must be heard for the coolness to be fully understood.

Hope that makes sense!