Next upgrade options

@saurabhgarg B&Ws do midrange really well. They also throw a very nice soundstage. My recommendation would be to change the amp. Your Luxman us very nice but you probably need something fuller and warmer without accentuating the top end. If you decide to go the route of separates, Pass Labs X250.8 with Audio Research tube preamp would be a good combination. You can also do all tubes and get ARC separates. Depending how much you want to spend you can try a used Gryphon Diablo 300 integrated. New Simaudio Moon North series is supposed to be excellent, there’s also a new ARC integrated amp. 

Stick with what you have but consider different speakers like Revel Salon 2's. You certainly have spent plenty of money already! Speakers always make the biggest difference in any system!

If you dare, Loan a CDT / CDP > DAC ( your own model ) to produce a Source and compare to to your Source in use.

There is the suggestion that the Hard Media Option will enable the Downstream devices to present in a way that creates an impressive End Sound and totally acceptable to your preferences, when experienced as a comparison to what is already on offer.

Limiting oneself to one source, or one version only of a Source is a limitation to the End Sound that can be experienced and in many cases a thoroughly enjoyed alternate sonic.

I have been at comparisons with DAC's and could easily live with a Third of what has been demo'd, some might win more favour if experienced for a longer period. Even with some models being notably different in how they influence the End Sound produced.   

The same happens for myself with Phonostages and Speakers.

In one home, there is more than one permutation for an assembly of a System that can totally satisfy the end user an additional Source is not too invasive. 

@audphile1 thanks for suggestion. I am tilting towards getting Diablo 300 or Luxman 590 axii. Latter is type A amplifier. 

@ghdprentice thanks for the suggestions. I was thinking to get a Type A Amplifier . Heard it is tube sounding. I am happy with most of other facets except getting a more fuller sound. 509z is the only amp I have tried.