I had that Atoll and I paired it with a Quicksilver Line Stage. In my opinion, that amp really needs a richer, more expansive tube preamp, such as something built around a 6SN7.
Here are 4 used options which, to my mind, all seem like good bets. Others on the forum may have additional thoughts.
https://www.usaudiomart.com/details/649914968-blue-circle-bc21-tube-preamp/
https://www.usaudiomart.com/details/649929030-schiit-freya-tube-hybrid-preamp-tung-sol-6sn7/
https://www.usaudiomart.com/details/649926920-black-ice-audio-f360-tube-preamplifier/
https://www.usaudiomart.com/details/649919944-don-sachs-model-2-line-stage-preamp/