Pros: Ample power, Spacious stage, Excellent clarity and imaging, Flexible connectivity
Cons: Volume pot action sensitivity
[This is just an impression. Sorry for lack of time to write up a full review, but I would simply like to recommended it.]
The combination of Phoenix and Ref-1 constantly amaze me with the the clarity and 3D-like soundstage. Many of my previous amp gave me an sonically "watching the view from TV box" that kind of feeling. Phoenix, instead, give me the "going out and see the real view" that type of realness and freshness.
The clarity and focusing are so good, that I don't need to "look for" each instruments. They just come out of picture and show their presence naturally. Music has been displayed effortless with ample power. This is the system you can constantly listen to and still amaze you from time to time.
Comparing to Decware CSP2+, an SET OTL tube amp, the soundstage of Phoenix is slightly father. CSP2+ gives me a nice sense of intimacy: the sound was so close to me that I can feel its texture and "body heat". CSP2+ is also an highly transparent and with excellent clarity. In comparison, Phoenix sometimes seems to be colder and I though that I would prefer CSP2+ over Phoenix. However, when I intentionally compare the sound of these two, eventually I still found Phoenix wins in its own strong point: absolute clear, well focused, and sharp sonic image.
And sometimes I though CSP2+ may gives more bass volume. But again, later I found the bass of Phoenix is still more solidified with real embodiment. The bass density is thrill to listen. One caveat is that that may need quality source such as Audio-GD Ref-1/7 to make that kind of bass possible.
The performance to value ratio is so good that makes you hard to find a persuasive upgrade. I has been hard to me to find a reasonably priced competitor.