I was approached by Audiotailor to review a new tube headphone amplifier with a unique circuit design. Of course I was immediately intrigued by the idea. I cannot reveal the details of the design, but it does result in their being two headphone outputs, with different sound signatures. This is the principle “feature” of this otherwise well built and attractive, but otherwise unassuming tube headphone amp. The Jade is made in China, and will sell in the USA for $350 shipped – an attractive price.
The Jade uses the current reigning king of headphone amp power tubes – the 6AS7G – as its output tube. The input tube is a 12AX7. The amp uses one of each tube, meaning that one channel rides on one section of each of these dual-triode tubes. I am a fan of the 6AS7G – it is a powerful, good sounding tube that offers a lot of inexpensive tube rolling options. And of course the 12AX7 may be the most popular 9-pin dual-triode ever. That does mean there are some expensive variants here, but there are also affordable options.
My Jade, which is an early production unit, did not come with any tubes, so I cannot comment on the stock tubes, but this is just as well – it surely would have come with Chinese tubes, and I wouldn’t even have used them. For the review I used primarily a GEC 6AS7G and a Sylvania 5751 – my experience is the 5751, which is the lower gain version of the 12AX7, sounds better and is quieter in headphone amplifier applications.
I mentioned mine was an early production review unit, and as such, there were two issues. One is that the 6AS7G’s tube socket was mounted too close to the PCB, and as such, the tube would not insert fully. I alerted Audiotailor, and they have assured me this will be fixed in the final production. It was OK for reviewing, but not acceptable for a buyer, so it’s good they will be correcting that. Also, the volume control was noisy when changing levels. No problem during listening, only when the volume was being changed.
Sonically, the Jade was terrific, but it’s a little hard to write the review since one really has to review the different outputs separately. One output is close to solid state – firm, detailed, deep bass, high resolution, very clear and transparent, and certainly not bright or edgy, but not lush or ripe, either. The soundstage was very well defined, but wider than it was deep. It was actually quite similar to the tube-hybrid Head Direct EF1 in sound, which is to say, excellent. Were this it’s only output, I would recommend the Jade, but not to people who were looking for a “tubey” sounding amp. Its sound is more “Yang” than “Yin”.
The other output was still very open and transparent sounding, but this time the sound was a little softer and sweeter on top, a little warmer throughout, and with just a little less deep bass, but with a little fatter mid-bass. Mids were on the lush side. The soundstage again was very good, but deeper than it was wide. In this case, were this the Jade’s only output, I would have happily recommended the Jade, but to people looking for a tube amp that was a little on the tubey side. So this output is the more “Yin” of the two.
What this does is make the Jade a terrific amp for people who own multiple headphones of different sound signatures. I preferred the “Yang” output with my JVC headphones, but I preferred the “Yin” output with my Beyer headphones. The differences are NOT night and day, but they are easily heard, and they do make headphone matching both easy and fun.
The overall quality of the sound from the Jade was very high for the price. The amp was very quiet. I enjoyed a very wide variety of music, and here again, sometimes I would prefer one kind of music on one or the other of the two outputs, although I normally cannot be bothered with such things. I like to set stuff like that and leave it, so once I identified which of the outputs was best on the specific headphones I was using, I would just leave them that way.
The Jade is not the very last word in resolution, or detail. You can't really expect that from a $350 tube amp, and you don't get it. But it's very musical, and highly enjoyable nonetheless.
Being a tube amp, it’s possible to tune the amp with different tube choices. I briefly used a Tung-Sol 5998, and it was just slightly less warm. So of course I slightly preferred it with the warmer of the Jade’s outputs. I did not try rolling 5751’s much – I only have RCA’s, Sylvanias, and GE’s, and I do not hear a huge difference amongst these – and what I do hear makes me prefer the Sylvanias.
The Jade will be sold web direct, and at $350 shipped to the USA, I think it’s attractively priced. For me it was definitely better sounding than the Darkvoice 336SE. It certainly compares well with the Head Direct EF1, and does offer the option of the two sound signatures. The Jade had no trouble driving any of my headphones well, but the lowest impedance headphone I now own is 64 ohms, and so the EF1 might still be a better choice for very low impedance headphones like Grados or Denons. And it’s not a giant killer – both my Singlepower amps were better, as one would expect them to be for the price and topology.
In any case, assuming Audiotailor seems to have resolved the small early production issues my review sample had, it gets an enthusiastic recommendation from me as a flexible, good sounding tube amp at an affordable price.