Tube Preamp for Pass XA25 under $3,000

Something not mentioned yet in the responses -- you said "the more challenging funk and rock can get a bit muddled in the lower range."

You are using Harbeth P3esr speakers -- the smallest bookshelves they make. The laws of physics place some limits on just how much low frequency material they can handle. If it is there on the recording, your amp is going to try to send it to the speakers, and your woofer is going to try to play it. To use your word, that can really muddle the entire sound picture, with the system exerting a lot of energy trying to reproduce sounds they are physically incapable of doing.

I have a set of Spendor 4/5s in my bedroom system. While I absolutely love the way they sound, they have clear bottom-end limits that some material, like funk & rock, can easily exceed.  I suspect that is more your problem than the preamp. Perhaps consider a subwoofer?

I agree with mlsstl. While the Harbeth P3esr is a wonderful speaker for much of the music you listen to, not so much for bass heavy funk and rock. 

Also, as an owner of the XA25, I believe a  preamp that provides 12dB gain or somewhat more is a good fit.   I own an Aric Audio preamp that provides a variable 0-20dB of gain. The gain is usually set in the upper middle of this range for the XA25.

I have been really busy with family and work.  I will say that the Backert has improved clarity and soundstage from top to bottom, and I am very pleased.  I guess predictably the high and midrange of my usual acoustic/vocal music has really benefitted.  However, the lower ranges are also definitely shaking out more clearly, including for more "complex" music like full on rock and funk.  (Sorry I am not really all that great at describing this stuff)  There is just more separation and clarity between the instruments even in the lower mid-range than the Freya plus. 

I realize it may not mean much, but the volume on the Backert stays between 8 and noon.  As mentioned, I am listening in nearfield, and my office is around 12x12, but it is completely open on one side (behind the speakers).  So the nearfield and size of the room may be helping with the lower gain.  It is really quite loud and fills my office at noon.

I will add that I do have a pair of REL T-Zeros that help the very lower end, but again, I have to really get the sound up before I feel they are pressurizing the room.  The Harbeth's are definitely putting out better low end on their own than before with the Freya.  

It is hard to tell if the sound is "thin" or "anemic" without comparing to another preamp.  If anything is hinting at a thinness, it is the high end, but it really might just be that the clarity has thinned out the treble more than I am use to.  It may be a matter of it being less forgiving of poorer recordings.  Certainly, the comments make me want to compare it to a higher gain preamp, and there is an Aric Special for sale.  Frankly, I do need a second preamp for my living room/HT, and would happily move the Backert there if it did not perform as well as another amp.  On the other hand, I don't need another preamp without HT bypass, and I don't see that the Aric's generally have that (perhaps saw reference to a bypass mod, but I could have imagined that).  I am going to think about this some more.  I really was planning on getting serious about a streamer, but may have to divert the funds to a another preamp.

Finally, with regards to the Cary, I would point out that I have a Matrix Audio DAC, with higher voltage, and the thread recently discussing this issue involved a Matrix DAC.  So that was concerning for me going that direction.  It might not have been an issue using unbalanced inputs from the DAC, but it was a concern for me.

Thanks for the input. 

Well I am glad to hear that the Backert is providing what you wished for. I am curious as to what voltage is provided by your DAC.

Regarding the Aric Special I own one of Aric's early versions.. It was replaced by Aric with the Super. One main difference between the two is that the Special has a variable resistor for the gain and the Super has fixed resistors with four gain levels. Also the Super has superior parts inside.  I would call Aric to discuss the differences and what he can do regarding the HT bypass. Whatever you decide you will gain from the conversation. Aric is great to deal with.

Suffice it to say, I second @mesch and his suggestion on reaching out to Aric.

Happy New Year!