I had Pass designed amps for nearly forty years. Threshold s/500 then Pass X350 with and Audio Research Reference preamp. Sonus Faber Olympica 3... I now have Sonus Faber Amati Traditional.
I had been hesitant to do a tube amp because of the reputation... tube life and biasing. But finally decided to go ahead. My dealer brought over an Audio Research Ref 160s.
I slid the 175 pound X350 to the side, so I could slide it back in for comparison. When I sat down and listened to the ARC Ref 160, within seconds I knew the Pass was never going back in. There was absolutely no competition. I acknowledged that the brick wall slam had disappeared. But every aspect of the sound quality improved, including the bass. More natural, forceful midrange, natural treble, musical... hugely musical. All the detail was there, but in proportion to how it should be, not unnecessarily highlighted. The bass was so much better, natural sounding, nuanced... not just a big bump... or slam. I instantly realized the slam from the Pass and most other solid state amps is phony. If you go to a concert... say Rock. The heavy bass sound arriving from the stage is what it sounds like on the ARC amp... not like the artificial brick wall (and die) sound wall of solid state. While I liked the slap in the chest... absolutely every aspect of the music got better... not by a little... a lot, overwhelming. So after 40 years of solid state amps, I just had to ask... why the heck didn’t I do this decades ago. I have no excuses. I had heard the ARC amps before... I just don’t know.
Over the last six years I have also had ARC Ref 160m monoblocks for two of those years. Outstanding. If I could have afforded them, they would have stayed.
FYI, I used to have an Aurlic Aries G2 streamer. I have heard the G2.2 has much better sound quality than the one I had.