ozzy
I used to own the PS Audio Direct Stream Dac. Running direct to my amps it was a bit anemic.
That’s totally understandable when you see this frequency response graph, the roll off in the bass with a 100k load starts at 100hz and gets worse as it goes down to 20hz, which indicates to me it’s capacitor coupled.
And that capacitor "could" be too small (impedance mismatch) when it sees the input of what ever amp/s you have or even 10kohm Passive preamp load as well, it could be much worse and roll off the bass even more than with 100k, and resulting in your "anemic " sound
https://www.stereophile.com/images/914PSDSfig04.jpg
Cheers George