X250.5 compared to Naim Nait5i

I believe that the Dali speakers are the limiting link in your system right now.
By the way your hearing is in good shape, Stereophile measured a 5 db peak in the treble, which sounds exactly as you described, bright and shrill.
Two speaker drivers operating in paralell will have a theoretical max 6 db gain in loudness.
A treble range lifted 5db above the midrange is the direct result of those redundant tweeters.
I do not understand why Dali insists on running two tweeters at mostly overlappping frequencies. My guess is that they do it as a marketing gimmick.
The speakers sound pretty impressive in the showroom, all that clarity...but later on, listening fatigue sets in.
I believe you will be much happier with the Maggies.

Thanks guys. Getting it now - I have had the Maggies hooked up with the bigger gear. Yes, the Nait and the Dali's sound very detailed and as complete novice I was impressed with this and still am. However, with the Maggies running off the Pass Labs 250.5 and Parasound JC2 I have a great sound which I would call more "realistic" if I had to label it, still, the Nait and Dalis at that price do sound great and I think they are a good first step. I know I will probably never be completely happy, especially when I read all the opinions here and there and I will always want to experiment and explore.....I guess I am straying from my first intention - to buy a nice sounding system, to it becoming more of a hobby - an added bonus as far as I am concerned!

Magnepan 1.6 is much better match with BIG TUBE AMPS like the Sonic Frontiers Power 3 which I am currently running.
The upstream source is absolutely important too.
I had tried numerous CD (YBA, Sony scd-1, Mcintosh, Esoteric, etc), DAC (Meridian, Audio research, Esoteric, Mcintosh, etc), preamplifers (YBA pre 1, McIntosh C2200, Audio research Reference 2, Conrad Johnson ACT, etc.) and power amplifier ( Pass, XA60, X250, YBA 1 & 2, McIntosh MC2301, MC250, etc)
All the above are excellent gear, yet, the only one sounds natural, real and good to my own ears are the following combination.
Tentlabs CD player, VAC preamplifier (upgraded capacitors: Mundorf Gold/Silver/Oil), Sonic Frontiers Power 3, AudioNote SET, Maggie 3.6
This combination compares to systems costing over $200,000 (Mcintosh, Sonus Fraber, Wilson Puppy, Audio research, etc)
; it just cannot compare.
I compare all the system to real, live music, and if your ears tell you to continue to listen; that is a good system.
Not listening to "Stereophile" or any person who has a "CONFLICT OF INTEREST" (they benefit from it: just like we should never listen to real estate agent, stock brokers, and especially, the lawyers; they all want nothing but your money)
Use your own ear; better yet, learn to play instrument and then you can tell which is real and which is just total horse shit.