shiit Freya+ muffles the base? Recommendation for preamp please

I have always liked the sound of B&W. So I recently upgraded my speakers to 804s. They’ve been sitting there for a while as I do not have a proper amp to drive them, till recently I got a Classe CA-2300. So I set everything up, excitedly!

my system got:

- Shiit Bifrost

- Shiit Freya+
- Classe CA-2300

- B&W 804s

so right after I turned on, I noticed the lack of base. The mid and high are sweet and clear. But the base is just not there, completely. A friend suggested to go from DAC to amp which I did. It suddenly brought forward all the missing base, tight and clear just like how it should be. Plus I am hearing some details I don’t get with Freya+ in the middle.

So I am wondering why the Freya+ is muffling the base? Just because it’s not in the league now? 
 

while without the preamp it got all the base, I do find it’s dryer and less musical. I do like how the tube preamp tune the sounds.. so any recommendation for a good tube preamp?

thanks all!

Azmixr