A few reviews:
https://musicphotolife.com/2018/07/astellkern-afutura-se100-review-premium-digital-audio-player/
http://majorhifi.com/astell-kern-se100-review/
Other notes
https://www.head-fi.org/threads/ast...pressions-reviews.882806/page-5#post-14339492
"Features aside, the sound is about 95% of the SP1000 (and imo the ak70mii is about 90%)."
https://www.head-fi.org/threads/inc...tura-and-a-norma.879337/page-15#post-14322448
https://www.head-fi.org/threads/inc...tura-and-a-norma.879337/page-13#post-14312748
https://www.head-fi.org/threads/inc...tura-and-a-norma.879337/page-12#post-14304990
"So I finally got a chance to audition the SE100 and do some A/B comparison with my SP1000 SS, here are sone impressions:
First thing you will notice is that the SE100 is A LOT lighter than the SP1000 due to the different chassis material, so if weight was a concern for you with SP1000, this should help.
I was only able to find a couple songs that's on the demo unit and my SP1000, so take it with a grain of salt.
The clarity is there. It's pretty clean up top, the vocal sounds pretty similar to the SP1000, and with a slightly more aggressive low end. With the SP1000, I think it wins on 2 fronts: soundstage and dynamics.
The presentation of the SE100 is pretty flat, ie its very horizontal. When I go back to my SP1000, I find the music to be a lot more 3D. Width wise they are pretty similar, but the SP1000 has more depth and height as well.
The next thing I notice is the dynamics. The decay of notes are better rendered on the sp1000, the sound goes smoother from soft to loud or vice versa.
So if you ask me, at half the price, the SE100 offers a lot of what the SP1000 does, but just with a less refined presentation. Hope that helps."