@mtbiker29 @simplystereo
I actually have had both Sopra 1 (and 2 and 3) and Diablo EVO.
I had Sopra 1 right before Diablo in the same room and system.
PrimaLuna Evo 400 separates
Nordost Heimdal 2 xlr and speaker
Lumin A1.
I found the Sopra 1 to have a bit 'more' bass, but not as controlled or defined as Diablo EVO. The Sopra 1 was overall - and everywhere else - less refined than Diablo EVO, and the Sopra 1 had a zingy mid/treble region that I had heard in Sopra 2 (more below)
In a different home/room and gear, I had Sopra 2 and 3. Room was 14x21x10 and I could not get Sopra 2 to stop beaming its tweeter. I had the same issues with Sopra 1 in another house/room (above). There is something with the Sopra series - to my ears - that are overly zingy and attention grabbing in the upper-mid/lower treble region that no matter what, I can't NOT hear. In half or more of what I played (Rock, Singer Songwriter, Folk, AltCountry, Jazz, Pop/Electronic), I couldn't get past that zing. In the Sopra 3, however, it seemed much more balanced, and might have broken in and gone away...
Take most of this with a HUUUUGE grain of salt. Why? Because, I never let any of the Sopras break in. I couldn't take the sound. BUT, and it's a big BUT, Diablo EVO never sounded that way even from the first minute - sweet, airy, and extended, w/o the grabby zing.
E.g. whey I'm wanting to go back to Diablo, but it is hard to tell what they changed, and I've never heard the previous generations... hence this OP.
Hope that helps!