Imac users, how do you set your levels?

[Jack71]

I just picked up an Ifi system in great shape to use with my Imac 24". I upgraded the speaker wire and connector cable and, wow! Great system. I'm wondering however, what the optimal way of hooking it up and setting levels would be. I know Klispch reccomends plugging into the line in on the back of the subwoofer but to my ear it seems to sound better plugging into the dock. I'm going to be using the computer and not an ipod as the primary source of music so I don't see the need to be able to mix audio from the computer and an ipod which seems to be the rationale behind plugging into the subwoofer. Plus, plugging into the dock should eliminate the ipod dock from the signal path, which can't be bad.

Also, I'm not sure how to deal with the computer's volume levels vs. the volume controls of the ifi system itself. Plus, if you throw itunes into the mix you've got that volume control to deal with as well. I'm afraid if I dime the computer and itunes' volume controls that I would be clipping the input of the ifi. What do you guys do?

Oh yeah, any good itunes EQ setting for Rock music would be appreciated as well. I tweaked the preset one a bit and it sounds decent, but I'm always looking to improve.