A couple initial thoughts of the Pro iCan with the Arya (in SS mode)
Comparison setup:
Tidal + Audirvana upsample to max pcm sample rate
USB —> Soncoz SGD-1
RCA to ifi, balanced to A90 (I could not not any noticeable difference in SE vs Balanced on the ifi)
ifi on low gain ~9.30, A90 on med gain ~ 9.30
All devices warmed up for a couple hours for good measure and the Arya is burned in
Detail Retrieval:
The best I’ve ever heard so far, (previous amps I have tried are: Topping A90, Cavalli Liquid Carbon, Gustard H16, Bryston BHA-1) I am sure that there are better resolving amps out there than the Pro iCan but for my setup and the Arya, the Pro iCan has the most detail I’ve ever tried. I feel that a lot of this has to do with better instrument separation. Besides that, I believe it is indeed more resolving outright with better textural nuance as well.
Tonality:
Obviously in SS mode, the Pro iCan is pretty neutral with the ever so slight warm shift. Everything is smooth without being smoothed over. In fact this is by far the biggest upgrade for me over the A90. On the A90, there are some tracks where I would avoid completely because the setup was a bit too shouty for me and I really could not listen for a very long time at all (something I did not do with the Gustard)
On the setup before the A90 (Gustard H16), I felt that the treble on the Arya was not too bad and I could handle it with almost anything I threw at it. When I had to replace the Gustard with the A90 however, I felt that the A90 was driving the Arya a little better, especially in the low end. The Arya was a little more punchy and dynamic with the A90 than the Gustard. After a little while however, the setup was getting too shouty for me and as I mentioned before, I started to avoid some tracks altogether.
Now with the ifi, it provides an even greater sense of dynamic punch, greater detail retrieval to my ears and the slight added smoothness means the Arya is no longer as peaky and shouty as before. The ifi also fuller sounding, like there is more substance behind the music. I do not know if this is just differences in volume as I cannot objectively volume match but I have matched it as close as possible with my own ears.
Imaging and Soundstage:
The ifi in SS mode provides me with a clearer image of each instrument in the stage, the A90 I found occasionally on some busier tracks to blend the instruments slightly. The soundstage is also a little more holographic and everything is just a little more spaced out. Its not a huge difference, its like taking a couple rows back in a concert hall. Imaging is also more accurate where I am able to more distinctly place vocalists on a stage. Say a vocalist is about 45 degrees to the right from the microphone, the A90 would place is much further towards 90 degrees while with the ifi, you can clearly tell that its middle right and not hard right.
Tube modes:
Overall I see a lot of consensus that the stock tubes are actually fairly neutral and don’t actually make a huge difference and I find this to be true. The tubes only add a little more warmth to the sound. That said however, I would not call it a gimmick or anything like that. I find it really enjoyable to be able to switch from the clean SS mode to a slightly warm tube/tube hybrid all in one unit, being able to suit different tracks and different moods at a flick of a switch was a huge appeal to me.
Xbass & 3D modes:
I did not really play with these so much as I found that I preferred them off most of the time, the Xbass however like the first setting on some tracks and sometimes go with the 2nd setting when I want to feel the wubs (the Arya handles it like a champ).
The 3D sound I am not that convinced by, it just made everything sound hollower
TLDR: Overall a fairly substantial upgrade over my A90 by completely outclassing it in every aspect as one would expect for the price, ever so slightly warm tilted sound in SS mode, smoother while being more resolving, gobs of power, well built, potential to tube roll. Probably never going back to a chip based amp after this.