New DAC or New Speakers?

Without question, change the speakers.  Differences between DACs are rarely night and day, but changing your speakers will have you up late into the night rediscovering your music collection.

Agree that speakers are where you want to start with system building.  And going from your Harbeths (86 db efficiency) to the Devores is a pretty significant change, requiring far less power to drive.  What about the Devore appeals to you? Another highly efficient speaker at about $20k that is really impressive is Wolf Von Langa Son.  A speaker that comes from the same sonic direction as Devore is Audio Note An-E.  Have you considered Tannoy or Fyne coaxial designs?  You can get some pretty nice models within your budget.  Last thought: if you like Harbeth sound a lot, ProAc and Spendor seem like natural alternatives to consider.

@mdalton I demo'd quite a few speakers, including Fyne and Proac (they were great speakers) and Spendor 2/3 Classics (that I really did not like) - the Devores were the only ones that wowed me. Hard to say that the wow factor wasn't attributable to the amazing room, the 50K DAC feeding them, etc.... But it was the only room that blew me away. 

I like the idea that they're more sensitive. I've discovered that I am a tube guy for sure. I love my VAC Sigma 170 amp that puts out 85 watts and I plan to use it with the Devores, but I see myself moving to a SET amp in my future. 

@wsrrsw Yeah, I recently learned that the room isTHE most important part of your system. I've got a buncha GIK

I have a totaldac D1, the least expensive of the bunch. I love it! It and HQ player give me give me the analog sound that I'm looking for.