Warming up digital in my setup

Your description reminds me of every time I have heard KEF speakers, especially the LS50.  Bright, hard metal tweeters aren't helping.  Try a speaker with a folded ribbon, like a Golden Ear stand mount.  

As for DACs, I tried a bunch of ESS chip DACs and found them all glassy and hard sounding.  I ended up with a Denafrips Pontus II.  I tried to avoid Chi-Fi, but after trying cheaper DACs from Cambridge Audio, Project, FiiO, and the Schiit Gumby, I gave in and got the Pontus II.  Still breaking it in, but it seems to avoid that harsh, glassy sound without losing any detail retrieval.

@zlone I'm intrigued by your Pi/Allo setup.  Early on, my first headphone setup used a Pi w/ HiFiBerry Hat.  It worked out really well to stream Spotify -- it was basically set and forget.  I still have a few raspberryPi 3 and 4, so I'll check this out and report back!    

@martinman I'm intrigued by your Pi/Allo setup.  Early on, my first headphone setup used a Pi w/ HiFiBerry Hat.  It worked out really well to stream Spotify -- it was basically set and forget.  I still have a few raspberryPi 3 and 4, so I'll check this out and report back! 

Worth a shot. I run mine with Moode, but Volumio is good too. Also use this low cost LPS:

I will be interested to hear your results.

If you have a tape loop, get a tube buffer. That should warm it up a bit. 

Definitely the phone setup.  Get a used Lumin u1 mini, Kimber Kable D60 spdif, used RME ADI2 dac fs. You will be happy. Quboz subscription. I use this setup in my den with PS Audio BHK signature pre and m700 monoblocks into Kef R11.  No glass.