Anybody could advise cables for my system.........

I used to use vintage audio gears in the past so I have least concept about brands and types of speaker cables and interconnects. Recently for experiencing different taste of sound I change my system and I'm now in need of information about interconnects and speaker cables to select.My system:

Transport Audio Research CDT1
DAC Audio Research DAC3
(Between CDT1 and DAC3 I use Audioquest AT&T
digital cable)
Pre-amp Audio Research ReferenceII Mk II
Power-amp Krell KSA250
Speakers Duntech Sovereign 2001(Single-wired

In urgent need of advise from any of you about interconnects(about 2m,Balanced-terminaled) and speaker cables(about 12 feet,either Y or banana-terminaled will be fine).
Thank you!

I've said it before, but:

I have all Krell gear and have recently discovered Silent Audio Apollo-A interconnects:

The best I've ever used!

My recent upgrade of interconnects and speaker cable resulted in Nordost Red Dawn interconnects and Alpha Core Goertz MI-2 Veracity speaker cables. It was a close call between the Goertz and the Speltz Anti-Cables. Both are exceptional deals.
Xtreme Cables are worth an audition in any system.
I have owned Audioquest (Crystal), MIT (750 Plus series 3), and Wasatch LC-550 (which I currently have for sale that meets your length requirements). I found the Wasatch to work great with Audio Research gear and was a clear step above my past two cables. Wasatch was founded by a past Kimber employee. Click on my ad and check out their website. I will be willing to let you try the Wasatch with a full money back gaurantee. You would have to pay shipping. I currently own custom made Verbatim cables for my Von Schweikert 4jr's.