Ok, so this is my first amp and set of components. I bought the CDT cl-61a (just like everyone else on this board) and a 4 channel Eclipse amp model EA3422 - 50W x 4 @ 4 ohms (link)

http://www.eclipse-web.com/products/amp/amp.html#EA3422

My HU is the Alpine 9807 with 4V preamp outputs.

I do not have a sub (yet), so its just the amp powering the fronts(I'm going to let the HU power the rears for now). I'm looking for help on what to do to make them sound their best. I'm using the passive crossovers that came with the CDTs, I left them at the flat 0db setting.

So, what do I adjust on the amp? I've done lots of searching on this board, and found some useful info...but none for my exact setup. I don't think my amp has the option to select "4V" to match the HU output, but I need to know what to do with the gain, should I use HP or LP, and about where should I set them? I know I'll have to make adjustments to what sounds good to me, but I need to know where to start and what to adjust. I'm very new to having high quality equipment and I just want to get the best out of it...please help! Thanks!

Use the HP for the fronts, set it at 70Hz-75Hz.

Set the HU volume at 3/4 (27 to 28). Have everything on flat (no bass bost etc). Put a CD that you know has good quality and relatively loud (many recordings are as low as -3db). Set the gains all the way down. Listen to the CD, raise the gains till YOU START hearing distortion, then, turn them slightly down. You want to get the max output at volume 27 w/o distortion.