RME ADI-2 DAC FS is it "All That", especially for under $2,000?

Yes, I thought about that, but for the extra there is some flexibility for room correction etc. I´ll get round to that once I´ve figured out the basics. And it´s German, for what it´s worth.

Although it sounds incredibly clear, when the volume is set in mid-range there is more audible white noise from the monitors, more than with the old DAC which is inside the pre-amp. Is there any reason why I should not set the volume to maximum and attentuate through the pre-amp?

I am very interested on hearing the comparison of the RME vs D90, I know the D90 measures outstandingly good and 4499 it is indeed a newer AKM but some people which have gotten the D90 have mentioned glitchy performance and said the sound is not engaging as with other similar DACs. Would you mind sharing @OP your upstream source? If you are using DSD with the RME you could take advantage of direct dsd but this will invalidate the DAC DSP and volume control in which case having a preamp still will be a good option.

Hello again. I did compare the RME vs D90 and my Music Hall 25.3 as well.

The RME and D90 sounded virtually identical to my ears. I really could not discern a meaningful difference, especially enough to sway me one way or the other. I am sending the D90 back, the added functionality of the RME is worth the extra $ to me. I will be using it as just a DAC, and will continue using my PS Audio preamp.

The Music Hall was less refined than either of the other 2, it did have more bass, but not as tight. It almost sounded like it had the slightest bit of reverb relative to the other 2. Which was nice in some ways.

Although I am good at critical listening, my ears unfortunately are not what they used to be.... :( Others with better ears might be able to pick out more subtle differences.

I have a RME coming in as well as a Chord Qutest and will compare to Chord 2Qute which I have had for some time.  The 2Qute has always amazed me with its clarity, drive and fullness, but then again I have alot of tube gear downstream from it.

I just have a question how were you able to get Topping 90 for $630 from Apos audio. I called them and they were not able to seel for 630.
Thanks, 
Great price for the Topping 90