Aurender ACS10

Keep going. What kind of tube amps and preamps. And long term intent. 

The answer is maybe but certainly not worthwhile, in my opinion. While the ACS10 may be somewhat dated, it’s still a very capable and well-engineered network transport (streamer/server). The additional cost of the N200 would be better invested elsewhere in your system—or simply left in the bank if you’re already satisfied with your setup.

Thanks for your responses . ghd please have a look at my profile to see my set up .

Thanks for adding your virtual system. Very helpful. Nice system. I have to agree with @lalitk. The N2x series was a notable improvement over the previous generations... but there is a real possibility that you would not get the, "Wow, that sounds A LOT Better"... that should come with an upgrade. But you might. 

I think your system would benefit from a N20. This would be a step up. Somewhere in here an upgrade of you preamp would be appropriate to bring it up to the level of your speakers should be considered. If it were me, I would do the preamp first (I am a big Conrad Johnson fan), then the streamer. 

OK ghd. At 90 years old soon I have no right to make mistakes for what will be my last improvement. So which preamplifier could replace my CJ? ARC, CJ, Manley, Cary, Cayin, new or rather used.