My dream for several years was to get a Parasound JC 2, but @ 4K it is out of my foreseeable budget. I was reading a passive preamp thread, which moved me to use the XLR outs from my Oppo 105 direct to my amps. fortunately, no impedance issues and wow, the noise floor dropped off a cliff. The only negative is any volume lower han full on seems to cause bit loss, BUT, now I am exploring passive pres. I went through a bunch of them over a decade ago, but like everything else, the tech has improved.
If I had $2700 I would buy the Troubador Passive preamp, It appears to be SOTA , but not in my current budget, so I found a Hattor passive on AudioGon and swooped it up.
My hope is by plugging the 105 into it, and opening th 105 volume control,l wide open and use the passive pre VC to better control volume. Hope to have it by Saturday, then a few days to acquaint myself with its functions and listen to some music