HELP: how to compensate too laid-back source

Dmitrydr, like the other poster here, I think a cable swap may be a good place to begin.

I'm using Acoustic Zen Silver Reference II, Matrix II and Hologram II in my system and enjoy the sound very much. The Silver Ref II and Matrix Ref II do sound very different, the Silver Ref II is leaner and more detailed because of its silver composition and the Matriz Ref II is fuller and rounder because of its copper design. But they share a signature AZ smoothness, and work well together in the same chain.

I used to own the Simaudio Moon I-5 as well, and am quite familiar with its sometimes thin, bright nature. Cardas Golden Cross helped to tame it to an extent, but I realize your problem is the opposite of what I experienced with the I-5 three years ago.

A recent thread commented on the differences between Cardas Golden Cross and Acoustic Zen Matrix Ref II interconnects. I never did a direct comparison, but the other posters did. They remarked that the Matrix shared the same smoothness and warmth of the Cardas, but with better extension on the top end along with a bigger soundstage.

While the Silver Ref II is by no means a bright cable, it is silver and will therefore be leaner than the Matrix Ref II. I think the Matrix Ref II may help you and will definitely be a big step above the Monster cable you're using. It's also half the cost of the Silver Ref II.

You should be able to snag a used Matrix Ref II for about $350.

I agree with Slappy, except that I think that you've already done it...backwards! I suspect that the Marantz has a much warmer presentation (and more perceived bass) simply because its top octaves are rolled compared to the more neutral NAD, and that has you cuddled up in its warm 'n cozy presentation...most of the time.
So try a fast, linear interconnect like a Blue Heaven or Pro Silway MkII. If still too laid back I'd return to the NAD or save some money and wait for the cheaper NAD 521BEE and maybe put a Harm Tech Truthlink on it like I probably will in November. Linear but not TOO wide open.
Probably easier to start by replacing the Monster with the Nordost or Harm Tech and maybe my PCK13Q+G power cord for a cleaner, linear presentation as well (RSVP), in the event that the culprits are just a cheap rolled off cables. If it's still too laid back for you then get another front end if necessary. The cables will still probably be fine for any CLEAN-topped CDP. Have fun. Ern

It's interesting what CD players have NAD's neutrality but significantly better resolution?
I'm quite confused: complex classical music was almost unlistenable on NAD, but a acoustic music from MA recordings sounded pretty good and natural, better then on Marantz. How to get both in one? I want smooth symphonic and chorals as well as naturally sounding drums from MA...

Ern, you may be right about a reason of "warm 'n cozy presentation... most of the time", but I think Marantz indeed produces much more bass... Well it's not an excuse for too laid-back sound :)

Before you do anything, including making judgments, let the CD player fully break in.

Years ago manufactures offered tubed buffers and other such gizmos to tame forward Cd players. Perhaps someone should create a solid state gizmo to add "presence" to overly laid back front ends? What comes around goes around, wait I'm getting dizzy.