@Hixs The T1 is a Tube amp (amp only), while this is a solid state DAC and amp. The X1S's sound is very neutral, and it is known that tube amps color the sound. So it really depends on whether you need a DAC, and whether you like coloration. If the answers are yes (to the DAC) and no (to the coloration), then this is a big step up.

Any idea what the output impedance of the amp is?

@Kdraper No idea, but it drove everything I had and them some to very satisfying levels. Believe me, I complain a LOT about amplifiers that don't drive my headphones well, and the amp in the X1S excelled with everything I had; soundstage-wise, as well as overall driving power. Volume-wise, I could not get past 11 o'clock, although volume != driving power.
 
That being said, I haven't tried it with anything above 300 ohms. But, the K7XX is notoriously power-hungry, and it did absolutely fine with them, as well as with the T90's 250 ohms requirement and others. IMO, output impedance shouldn't be on anybody's list of concerns for the X1S.

@avitron142 @Hixs Good review, but I do want to point out the T1 is NOT a tube amp. It is a tube DAC with a built in amp. IMO the amp section is not very good, so I would imagine the X1S beats it on that front.

Looking forward to trying this out later on the tour.

nice write, glad you enjoy yours. the only one thing i can say against the 4th gen x1 is that I cant get pass 8 oclock when the knob can turn from 7 to 5. I even tried it with 250ohm dt880 and hd600. maybe its only me, but that little range of turn, its very hard to adjust to my liking and enjoy the x1. reading from the comments, it seems like it is still the case with x1s. but on the other hand though, it can drive some small speakers to a pretty good level and itwas designed to do that with the x1 x2 x3 combo.

Cool. These sound like they will fit lcd-3 quite nicely, if I get a pair? Or you think the power my be lacking just a touch? Thanks for the in-depth review!

thanks so much for the review. i was excited when i first heard about this and wanted to hear some comparisons especially to the schiit stack, and i like the fact that i wouldn't have as much room taken up since this is a combined dac/amp. definitely might be in the market now.

@BenHolmes I wouldn't say they can't drive the LCD-3's, as much as it may not be up to par to bring out the best of such an expensive pair. I can tell you though that they held up nicely with the T90's, which is no sloucher itself; so I'm guessing that it would do great with the LCD's too.

@PoRidge The X1S is powerful too, bu the volume knob is very refined, and I had no problem finding the volume that worked for me. 

Great review! I have also had the X1S for a few weeks and just received the HE400i for an all Chinese combo. The design is great and everything is easy to use, the amp section also powers my cans to some earsplitting volumes when cranking it up. Enjoy!

Actually the Aune T1 has the unusual arrangement of having a tube buffered DAC and a solid state amp. It uses the 6922 / 6DJ8 / 7308 / PCC88 family of tubes. I don't doubt that the XS-1 will outperform the T1 although the T1 works fine with my HD600s and is a good introduction to tube rolling.

Great looking device! Any chance of having a look under the hood?

Good review  @avitron142 , congrats!
I was curious about this product and now your review answered many of my questions.

@DJScope This sample is part if a tour, so we can't exactly open it up
 
@Baycode I'm glad I could help!

You feel it's miles above the LH Labs Geek Out 1000, what about the Pulse line?

@foreverzer0 Sorry, never tried it.

Would this work well with the Philips Fidelio X2?

What about iFi iDSD Micro, Gustard X series, or Schiit Yggdrasil?

@The Lamonster @foreverzer0 Can't answer either of your questions, never listened to the equipment you have listed. But @foreverzer0 comparing this against a $2200 DAC is not really fair, IMO.
 
@Sundown I believe you can only listen to one at a time. This was done to avoid a scenario when you have all the inputs plugged into, and want to listen to them at different times, but everything plays all at once.

Doesn't sound fair but with the value getting increasingly better, it's not dramatically far off anymore. Many say the $500 iFi DSD Micro is 90% of the Chord Hugo, which is between $2-3k range. IMO, asking how a $300 Xune X1S compare to a $500 DAC (that is 90% of a $2500 DAC) isn't completely left field these days. Also, it's to give an idea if all things being equal, a Yggy being 9/10, how would a X1S be on that scale.