Pros: Many inputs, solid case, also a great pre-amp, no lack of power, excellent absolutely neutral sound, digital volume control, remote is handy.
Cons: Quite a bit of power used and heat generated, heavy, data connection cable looks like an afterthought, only worth getting for balanced headphones.
Possibly the hardest thing to describe about the Phoenix is it's sound. Simply put, it has no particular "sound", but simply lets the music through as it is, without imposing anything upon it. For the purist who seeks this, it is perfect, but it's not the kind of amp that will impress you on first listen, but usually only after switching immediately to a lesser amp and realising what is missing.
The soundstage with balanced headphones is wide. This is even very apparent with speakers when used as a pre-amp. With balanced Grados the result is like sitting in the front row when the band is stretched across the stage, for example. This is not lost in the slightest in complex and fast-paced music at all, the question of power never arising.
The two amps I have had the chance to compare the Phoenix to directly are the Luxman P-1 and Audiovalve RKV Mark II (upgraded with OPA627 OPAMPs). The Luxman, having only a single-ended output cannot duplicate the Phoenix's soundstage when balanced, but offers a touch more punchy and musical single-ended presentation than the Phoenix offers with single-ended headphones, but the Phoenix very slightly bests it in the treble. The RKV too has a noticeably more "fun" presentation, with awesome bass, more so than the Luxman, but the treble is a little rolled-off and doesn't present percussion instruments with nearly as much ability or detail. There are times I wish the Phoenix had a little more punch to it, especially as my main headphones are HD-800s.
As for the design, it un-ashamedly takes a leaf out of the Mark Levinson book, putting the power and electronics in one box, while the other purely only has the amplification circuits and volume control. While the RCA and XLR sockets are high quality, one might wish for better quality DC and ACSS sockets and the data cable is clearly a kludge, being a modified serial cable. Otherwise, it's a beautiful unit in the flesh, with a solid aluminium chassis and, unusually, a remote milled out of solid aluminium. However, considering the cost of having a Beta 22 built, for what you get, it's a comparative bargain, especially if you pair it with an Audio-gd DAC that has ACSS output and also use it as a pre-amp. Audio-gd also, thankfully offers to pay for return shipping if anything goes wrong with the unit during the warranty period, which is often a concern held by people buying gear from China.
Edit: Since this review was written, the case venting, data cable, ACSS sockets and ACSS cables have been upgraded in the design to address the concerns mentioned.