Arrived and had a good test.
There is a background hiss with SE846 but only hear it between tracks, barely noticeable during music (though Note 4 is dead silent).
Using default Android 5 on S6/Note 4 I detected popping noises on the S6 but perfect with Note 4. Just noise/crackle if connected to my Tab S 8.4.
So focusing on the Note 4 (as not good with other two) it sounds stunning with more richness/smoothness to my ears, but the Note 4 output itself is also...