Hello @Robert1976, this is my second response to you so I may repeat some things. You have gotten many helpful responses and the expected skeptical ones as well. Recall I have Nucleus+ on my network and Tambaqui DAC with revealing SS electronics and incisive (but natural) speakers. When I got my Tambaqui, I certainly thought I was done. But as you state, many recordings sound a bit harsh, while most sound amazing. Yes the Tambaqui is a Streamer and DAC, so I did not think I needed a separate streamer. BTW, I have taken the small steps as well. LPS on my Nucleus. Using Supra Cat 8 cables. Upgraded Switch - Silent Angel Bonn 8 (I am sure there are better), EtherRegen in front of the Tambaqui and now also Muon Filter in between EtherRegen and Tambaqui. Everything helped some, the Muon #1 and the EtherRegen #2.
But the addition of a separate Streamer was a bigger improvement. @Verdantaudio is a great resource and he has helped me by phone. I like the Antipodes stuff, but went another way, keeping my Nucleus+ and adding the Auralic Aries G2.1 streamer. It is. not cheap but lots less than some you may be considering.
Aurender has great reviews and following, but not a Roon device and I am into Roon for good. The Innuos Statement looks nice..check out the power supply upgrade by Sean Jacobs.
When you look at the expensive digital stuff, it all has very enhanced power supplies. So following the lead of another contributor here, I modified my Aries with a custom Sean Jacobs power supply and custom K-S umbilicals. This was not cheap, but adding the power supply to the Aries G2.1 was less than other top end streamers, and I wanted to keep my Nucleus so I did not need (example K-50) a Player and streamer.
OH MY. When I first hooked up the new power supply to my Aries it was incredible.
I did not know how much better my system could sound. Much more engaging, better soundstage, fuller and more emotionally involving (if I can get away with saying that), more lifelike and SMOOTHER. I went back to some of the harsher recordings and they were so much more listenable (Californication, Chicago Beginnings).
I kept the Muon filter in the system, but found with the new power supply, the EtherRegen was not such a big deal and put it in my other system, along with another Muon filter I like it so much).
I also love my smooth Kubala-Sosna Elation Cables (including USB and power), but have not heard yours. Of course room treatments help as well, but you can only do so much sometimes.
You have a great DAC. I am sure there are amazing tube DACs, but I think many discussed are inferior to the Tambaqui. As someone told me once here, you have a Porsche of a DAC but are feeding it cheap gasoline. The front end of digital prior to the DAC is hugely important. And, having a Nucleus as player, a good streamer with USB to a great DAC gives you the flexibility to change any of the three of them down the road, or simply try other USB DACs to see!