Tuning my system towards a darker tone

I am trying to tune my system in a darker direction; as I have a bright ( lots of glass) listening area and have been directed by my interior designer ( aka wife) not to add room treatments.  Starting with power cords, then possibly ICs would like to find a natural sounding power cord but with a darker tone.  System includes: leben cs 600 amplifier, Linn Akurate Streamer DAC, Feikert Volare TT, Luxman CD player.  Current power cords include Luna, Audio Art and Raven.  Note: my speaker cables are not in play as they are within the walls and were picked to appease building codes in our area.  My price range for cord 500-1000.


Maybe they should not cross at all. They could point straight across the room.

I asked because I have the similarly designed O/96's and they sound terrible pointed straight out.  In my room they sound best with the tweeters crossing right at the listening position which is how John DeVore suggests as a starting point when adjusting toe-in.  Even opened just a little bit loses a lot of sound quality/soundstage in my room.  I thought you were suggesting some form of extreme toe-in which piqued my curiosity as I had never tried that before - until this evening.  Nope, that degrades sound as well so back to the way I had it.
Well, really depends. Going only on the measurements, it does seem you can reduce the treble quite a bit by using the toe-in.

Obviously, don't make them suck. :)
If you decide to experiment with cables,research Triode Wire Labs. Their power cables are very effective (especially with digital) at taming aggressive high frequencies. Thirty day audition period to return if they don't work out for you.
Thick drapes and fine tuning the speaker positions as others have mentioned will help.
Erik suggested WireWorld Eclipse interconnect/speaker cables.  These are good to help calm down things, but only if you get the "copper only" cables. 

In addition, get some basic level copper-only gold-plated Audioquest power cords.  The combination of their copper-only solid core conductors and gold-plated plugs will really help calm down the harshness and highs.  It will also smooth out the sound compared to stranded power cords.
I recently ordered aTriode Wire lab cord and await its delivery !
Apparently stuck in USPS morass