Help with NAD C320BEE brightness. Break-in???

I don't think I'd squash down the top octaves with VD cables just yet. The NAD has a nice linear top end. Let it break in longer, and perhaps reassess room damping issues in the meantime, as well speaker toe-in/sidewall stuff.
I'm a firm believer in spectral tuning via transducer matching rather than cable coloring, except for very small adjustments. I use a Harm Tech Truthlink to soften FM birdies on my MD100, for example. The VD take too much of a treble cut, and therefore sacrifice much top end air, IMO.

I am driving a pair of Magnepan 3.6s with a C320BEE and the sound is glorious. This was suppose to be a temporary set up a little over a year ago while I procured an upper end digital amplifier but, the sound is so natural and sublime that I have been reluctant to change anything. Even the power is enough for my limited volume listening.

The C320BEE is a very good solid state integrated amplifier within its natural limitions. Much better than the price would indicate. A classic example of quality engineering no longer being a justification for an expensive product.

If you have brightness problems then take a hard look at your source. I am using a Jolida JD-100 and, the sound is awfully nice.

I returned the NAD and purchased a NEW MODEL Jolida 1501 (Four months old – Silver faceplate) used on Audiogon for $500.00. This was the best choice I made for my room/system. To me the Jolida is a solid step-up in performance. Beautiful solid bass, warmer and detailed mids & highs. It's in the same ballpark sound wise, as my previous system -- Krell KSA 200s / McIntosh pre. set-up.

For $500.00 it would be hard to beat. Keep in mind this is the New Jolida 1501 with new factory upgrades as the standard. I am very happy to own the Jolida!!