The long / Narrow room - system configuration

My room is the same size. Ceiling slopes slightly from one and to the other (8' to 10').

Using 25' single ended IC's is fine (and actually the preferred way to do it IMO), but they should be a good shotgun design like MIT, Straightwire, etc. And always, always point all IC arrows to the preamp, not in the direction of current flow. Lift all grounds on your AC plugs except the preamp, and you shouldn't have any moise problems at all.

As for room setup, you're doing what most folks do (getting back as far as possible from the speakers) but which you shouldn't/can't in a room that narrow. You didn't say what kind of speakers you have, but pull them at least 4 ft off the rear wall and +/_ 3 ft from the side wall with almost no toe-in (yes, I know -- they'll be close together.) Then place your listening chair (your ears actually) about 8 - 10 feet from the speakers.

This is called "nearfield listening" and is the only setup possible in a room like ours, if you expect to get a life-like soundstage.

I would just add to what Sns said. Theoretically, long wall placement is desireable for soundsatge creation because with the speakers still reasonably close together (not over 8 ft c to c) you eliminate those nasty image-killing second arrival reflections off the side walls.

However there is a minimum room size for this to be practical, when you take into account the fact that you need some space behind the speakers (the most for dipoles) and you don't generally want your chair or couch hard up against the wall behind. After a lot of analysis and experiment, I think this minumum size is 16 x 24 (or larger.)

The world seems to be full of 12x 14, 18, and 24 foot rooms, and it's that limiting shorter dimension that ultimately forces a lengthwise arrangement with a nearfield listening position.

Fjn04, it sounds like you're getting there pretty fast! One thing I would recommend after reading your room description is:

To symmetricalize (is that a word?) the acoustics of your room by creating an absorbtive area on the right wall pretty much equal in size and exactly opposite the opening to your dining room on the left. There are so many ways to do it, I'll leave that up to you.