Audio-gd Phoenix

Not mass market gear, but if you are looking for an enthusiast class A headphone amp that can drive very power hungry headphones the Phoenix remains a solid choice as long as you have the space for it.

[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.

Lots of ink has been spilled about this amp already. The “big thread” on the Audio-GD Phoenix is VERY long – so long it’s only useful as a running dialog about the amp – reading through it to glean information has become very difficult. But it shows that there is a lot of continued interest and excitement for this amp, which is in my experience somewhat unusual for an amp that sells for more than $1,000. So I was very excited myself to get the chance to listen to it.

One thing I DID glean from the big thread, however, was that a review of the Phoenix without a pair of balanced headphones would be less than useful, since it is a fully balanced design, and that this is a big part of what makes it what it is. As luck would have it, a pair of 600 ohm Beyerdynamic DT880’s that had been recabled for balanced popped up in the FS forums about the time the Phoenix arrived. This was almost too good to be true, since I am thoroughly familiar with the DT880 (as well as being a big fan), and I would be able to compare the same exact headphone balanced and unbalanced. SO I bought the balanced 880/600’s, and all was well. I already had a balanced DAC (the Music Hall dac25.2, which when used balanced bypasses the tubed output stage). So my review of the Phoenix is primarily using that configuration – Denon CDRW1500 > toslink > dac25.2 balanced > Phoenix > DT880/600 balanced.

When the Phoenix arrived, I was taken aback at how heavy it was. This is one SERIOUSLY built amp. It’s also cosmetically beautiful – if you are into audio gear as jewelry, the Phoenix will tickle your fancy in this regard, I’d wager:






I was further taken aback at how HOT the Phoenix is. I guess it’s biased HIGH into Class A, because this thing is very hot, even at idle. I had to put my DAC up on some very tall isolation feet so there was enough air circulation above the Phoenix. There are 2 chassis, and it’s better to put the “control” chassis above the chassis with the headphone connectors from a heat management perspective. The Phoenix’s chassis gets warmer than the chassis of any tube amp I own. No kidding.

I broke the amp in for 300 hours before reviewing, and with the 150 the factory puts on, that’s 450 hours. Should be plenty, and I did not notice any change in sound during the time I did my auditioning. The only operational “quirk” of any kind I had is some very slight clicking when using the volume control, as other users reported. But it was very slight. And when using the remote control, there is no clicking when changing volume. Otherwise, the Phoenix performed flawlessly.


SOUND

The Phoenix is, without a doubt, one of the smoothest sounding solid state amplifiers I have ever heard. It has an effortless, delicate, nuanced delivery that will melt the heart of even the most die-hard tube-loving headphile. The overall presentation is just slightly dark. I can see why HD800 owners like the Phoenix – the very slightly laid-back treble would no doubt mate well with the HD800’s treble presence. Same with the DT880 – there is no question that the Phoenix delivered the best sound out of the DT880 that I have ever gotten from a solid state amp, and indeed with the balanced DT880, the best sound I have ever heard from any DT880, period. The balanced DT880/600 and the Phoenix provide a level of performance that is hard to imagine unless you hear it. It’s wickedly good. You could listen to it for hours and hours with no fatigue, and with a deep sense of engagement.

For example, during Joan Osborne’s aching cover of “I’ll Be Around”, I noticed at one point while typing the sentence above that I wasn’t typing anymore. I got lost in her voice. I mean totally lost. This doesn’t happen to me nearly as often as I wish it did. But the Phoenix was able to deliver goose-bump thrills on a more than just occasional basis.

Part of the magic is the absolutely spooky dark black background that the Phoenix produces. This aides in both dynamics (which are very good but not the absolute best I have heard), and in transparency. The Phoenix is definitely highly transparent sounding – it is completely free from any sort of veil or haze or glaze – it provides a pure, wide open sound that serves all kinds of music very well.

The midrange is very full and rich, but in no way syrupy or fat. But it is less thin than many other SS amps, even in the $1K+ price class. I don’t have any of the other high-end SS amps I have reviewed around for reference any more, unfortunately, but I have reviewed or owned the B22, RSA Apache, Blue Circle SBH, ALO/RWA Amphora, Meier Opera – all some nice SS amps. And at least from memory, I would take the Phoenix’s midrange performance over all of these. Joyc e Cooling’s fragile first-alto vocals on “This Girl’s Got to Play” were sumptuous, as were Mae Moore’s on “Love Will Bring You Back”. Female vocals are absolutely wonderful on the Phoenix. Guitars had nice crunch and tone without sounding overly forced.

Bass performance was interesting. Extremely tight and deep, and well defined, and very articulate. There was just a very little bit less punch than I expected, I guess, but I didn’t consider this a deficiency – the bass was very well integrated with the overall sound, and while I have heard amps with just a bit more bass weight, the Phoenix’s overall smooth nature meant that this did not yield any brightness in the overall sound. Far, far from it, in fact. The Phoenix is unfailingly smooth and rich sounding, without sounding in any way slow or lacking in detail. Listening to “Inhaler” from Hooverphonic’s “A New Stereophonic Sound Spectacular” showed the Phoenix to deliver very musical bass of exceptional control, but with just a bit less weight at the bottom than I get from other top tier amps. But again, this is very slight.

Higher up, things are also really, really good. Treble detail is better than some amps that sound brighter. The treble is so smooth and pure that it doesn’t call attention to itself (which is a good thing), but small details still come through. For example, there are some triangle strikes in part of “Inhaler” that come though very nicely in spite of that song’s waterfall of instrumentation. Ditto some triangle strikes in Mastodon’s “The Last Baron” from their new “Crack the Skye” (which was outstanding via the Phoenix). If all SS amps had treble like the Phoenix, the world would be a far happier place, IMO. The ability to be simultaneously so detailed and so smooth is a big part of what makes the sound of the Phoenix fly, IMO.


Imaging is exceptionally well defined, and this is sometimes a hard trick to pull off in an amplifier with as smooth a treble as the Phoenix. Many people confuse image specificity with an exaggerated treble which pushes detail in your face. The Phoenix does no such thing – it is a very natural soundstage, with outstanding image stability and definition, with a great sense of space created. It does seem to be a little less “out in front” of the head than some of my better tube amps, but it is nonetheless very, very good. Width of the soundstage is also excellent. One would hope that an amplifier in this price class would contribute to excellent soundstaging (which of course is dictated largely the headphones), and indeed, the Phoenix does very well here.

I will say that the Phoenix did work a little better for some headphones than others. All of my 600 ohm Beyers sounded nothing short of wonderful, even single-ended. This is a Beyer-lover’s amp, for sure. I can’t wait to hear with with the new Beyer T1 when my pair arrives. But the Beyers were a better fit with the Phoenix than the JVC DX1000’s were. While I thought the DX1000’s sounded excellent via the Phoenix in many respects, the slightly dark sound of the DX1000 paired with the slightly dark sound of the Phoenix was a little TOO dark when used in combination. Not so much that it renders the combination unenjoyable – quite to the contrary, I still enjoyed it. But if the DX1000 were my only headphone, I wouldn’t choose the Phoenix. Similarly, if the Phoenix were my only amp, I wouldn’t choose the DX1000. The DX1000 sounded a little better on my Decware CSP-2 and my Darkvoice 337 than I felt they did on the Phoenix (both of those of amps were about the same price as the Phoenix, when the price of the tubes in them is factored in). I wish I still had my Denon D5000’s – I bet they would sound great with the Phoenix if my memory of them serves me. I also don’t have AKG K340’s anymore, but I bet a balanced pair of those would be dynamite on the Phoenix.

A word about balanced versus SE performance – since I had both balanced and unbalanced DT880/600’s, some easy comparison was possible. I would say that the sound in balanced was 15-20% better than SE – much higher than I expected. The soundstaging was better; the overall sound was more nuanced and delicate; decay and hall acoustics were easier to hear. I would highly encourage owners of balanced headphones to find a way to audition them with the Phoenix. I also think that spending $1,200 for this amp if you don’t own a pair of balanced headphones, or plan to buy some soon, probably isn’t the way to go. It’s still a great amp, but you’d be paying a big premium for a benefit that you couldn’t use.
 
I did also use the Phoenix as a pre-amp in two settings.  I first used it in my "he-man" speaker rig.  In this setting, it was OK, but a far cry from my Cary SLP-05.  In the context of my pretty high-end speaker rig, I felt the Phoenix was outclassed.  Good, but not great.  I also used it as a preamp to drive a pair of Dynaudio powered monitors.  In that context it was much more comfortable, and sounded excellent.


SUMMARY

The Phoenix is a world-class solid state headphone amplifier that truly shines when used with balanced headphones, but is still very good running SE. When driving a pair of balanced DT880’s the sound was so enjoyable it was hard for me to do anything BUT enjoy it. I had always kind of poo-poo’d the whole balanced thing for headphones, even though my speaker-rig preamp and power amp are balanced. Shame on me. Now I get it. While the combination of balanced 880/600’s and the Phoenix push the $2K mark, the price is fully justified by the performance, IMO. In fact you can easily spend more and get less. The Phoenix is just a touch on the dark side, so it’s a good idea to consider the pairing headphone a little carefully. But having done so, the Phoenix is a magical bird, indeed. Based on my prior experience with SS amps in this price class, and I have owned or reviewed more than a half dozen, I believe the Phoenix is also an excellent value, even at $1,200. Super-enthusiastically recommended. I was sad to see the review loaner go.

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.