New system too bright.Will different cables help ?

Start with the DH Lab cables, if they are the silver plated copper ones they can sound bright. If that dosent do it, find someone who will help by switching some of their stuff in and out untill you track down the culprit. Some combinations just dont gel, so it dosent necesarrily mean you have any one component thats 'bad'. Take some time and narrow it down.

In your case, I feel switching out the DH Labs for something like Acoustic Zen will make a significant improvement. I used Silversonic T14 for some time and felt it was quite lean and revealed the nasties present in my various systems. The AZ line of cables are extended and smooth. Even the Silver Ref II is a smooth sounding cable. You might give the AZ WOW a try.

I own a few different NAD pieces, the 502 being among them, and I feel they tend towards being musical, not bright. I've never heard or owned any Myryad gear, but it could be they are more revealing than the NAD components they replaced and combined with the DH Labs cabling could be the cause of the increased brightness.

It's easy to see from the various opinions regarding cables how one can
get hopelessly caught in an experimental tangle of interconnects.
Everyone who has posted has good experience with the recommended
cables in their own systems, yet few can agree on the best cable
solution, and none have experience with the mix of components that
"Khm74" has. I maintain the best solution is a careful and methodical
component swap starting with the source or amp while utilizing a good,
inexpensive, neutral cable such as Signal Cable Analog Two.

I agree with Ozfly.MIT tamed the forward upper treble on my Thiels.
The Thiels now sound super!

Dont get suckered into buying a new amp/speakers etc..many say cables are a bandaid.
I say, if they work thats all that matters.

Cables can make or break you, but you need to remember that NAD stuff tends to sound overly warm and smooth in exchange for details. I am a strong advocate of proper power delivery/noise control measures and will strongly suggest you start there. The more revealling a system the more harsh noise (glare) will sound. If you start at the source you'll be able to tell if this is the right direction and then work your way down the signal path. Since digital equipment consumes so little power you can do this rather inexpensively. Get a little 2-3 ampere ONEAC isolation transformer from eBay ($15-25), clean all the contacts inside & outside w/ DeOxy and treat them w/ ProGold. Use that on your CDP and listen. If HF glare goes down then keep working on the upstream side of your player until you can improve no more. Then move down the signal path. I would get a Porter Port cryo'ed outlet and a decent DIY based design power cord for the CDP(Bob Crump, Chris VenHaus). I have a CEC built belt drive transport and it reacts very favorably to power cord upgrades. The same goes for my little sister's NAD receiver. I had a surplus military grade, silver plated copper, Teflon power cord hardwired to it and the improvement was stunning. Bass improved tremendously and the vocals became smooth and airy.

Here's the testimonial of someone who followed my suggestions:

Power conditioning and cryo treating

I have tried DH Labs Silver Sonic interconnects and they just didn't make the cut in my system. Perhaps some solid core copper like the Straightwire Rhapsody II's or Tice PC3 will be what you want. Don't forget to allow your system at least 100 hrs for break-in.

With psychic power and primal intensity,