My search for a great sounding headphone rig that rivals my former high-end 2-channel system (that I miss so much) continues, and has led me to the AudioValve Solaris amplifier, designed and hand-made by Helmut Becker in Kassel, Germany.
The Solaris is a "universal" amp in that it is a genuine integrated that can drive any headphone including dynamic and electrostatic sets, plus it can drive loudspeakers with its binding posts on the back. It is a dual-mono design, and delivers up to 12 watts per channel of OTL Class A tube power, has multiple inputs (balanced, singe-ended, and even a MM phono preamp built in) has front-panel gain control and a balance control. It also has pre-outs in case you'd like to use it as a preamp for external amplification. It uses Russian 6GV18 (ECL85) tubes, not exactly standard fare, and the owner's manual warns against "tube rolling" and states that removing the glass top before the 3-year warranty expires (without factory authorization) will void the warranty. Solaris is continually servo biased, so the tube performance remains at peak for their life.
Solaris is a handsome looking amplifier. I am not normally seduced by looks and bling, but I must say the gloss black exterior, gold knobs, and large window to view the tubes has improved the looks of my home office listening area immensely. It also comes with a simple remote volume control, just in case you need to sit more than arm's reach from it. The amp is large, about the same size as a standard home hifi receiver, and weighs in at about 10 Kg (22 lbs.) My version does not have a DAC built-in, but it is available in that configuration.
So how does it sound? I use a signal path that is a Roon music server, player is Sonore Ultrarendu, DAC is Schiit Yggdrasil (V. A2) to the Solaris, and currently listening with MrSpeakers Ether C Flow and Sennheiser 650 headphones. Cables are from Audio Quest and Zu Audio. I played a variety of music since my taste is somewhat eclectic, ranging from Mahler's 3rd to Killing Joke, Steely Dan, Depeche Mode and Herlin Riley. I also listened for a while to some Motown soul courtesy of Qobuz high resolution streaming.
The sound from Solaris was universally excellent, with a slight bass emphasis that should come in very handy when using electrostatics. It seems to have a bit of a house-curve built in rather than being ruler-flat and to my ears it sounds very good. It brought my dynamic headphones to life. One of my ulterior motives for choosing Solaris was its ability to also drive electrostatics, but is has made my Ethers come to life in such a way that I am less inclined to make that investment. Although... I hear Voce calling my name.
There is absolutely zero detectable noise from the amp and dynamics are shocking. FR is beyond human hearing and THD is rated at 0.002% @ 1 watt. This amp can drive headphones with authority, clarity and musicality. Switching over to loudspeakers, the sound was equally impressive into my ancient set of rebuilt Infinity RS-IIs that adorn the back wall of my office. Very nice.
I said in the beginning of this post that I was striving to replace the sound of my old 2-channel setup. I used to own a Shindo Cortese amplifier, and the sound from Solaris very much reminds me of the Shindo with its F2A tubes and custom hand-wound transformers. What I hear now is very close indeed. So close that I find myself missing it less...
Solaris is not an inexpensive amp, but for the capabilities it offers I feel it is well worth the money. It comes in at less money than a Blue Hawaii SE, and has more capabilities, for example.
I highly recommend Solaris as an end-game amplifier.
Thank you so much for your impressions David, greetings Helmut