Good point Squeegy...
I have definitely heard differences using different interconnects. There are some I stopped using because of an effect similar to what I heard in the Rotel phono stage. More extended highs and lows at the expense of some midrange. The ones I use now are all very basic. Copper, many fine strands, not twisted, foil shield. They seem to sound just a tad more open than "in the box" cables, without having any dramatic effects.
Something that slightly favors the frequency extremes might work really well with the NAD. Might make the NAD sound a little more like the Rotel did, but to a lesser extent. Might soften the sound of the NAD a bit without overdoing it...
Thanks for the kind words guys!!!