i tried comparing a Z1060 and an A865 a few months ago using their respective headphone out and paired those with a Sony MDR CD900ST and Sony MDR EX800ST, i find that the Z1060 sounds bigger and livelier compared to A865. this is both set to flat and all enhancements set to OFF. to make the A865 on par with the bass of the Z1060, I still need to enable the "Clear Bass" enhancement of the A865. Treble of the Z1060 gives better separation possibly because of its soundstage and gives more sparkle as well.
maybe the Z1060 sounds "colored" than the A1060, and i still find that the A865 sound "boring"-- it always remembers me of a cowon J3 set everything to OFF with EQ set to normal. I didn't compared both with an amp since it adds another "color" to the chain and I didn't bring an amp that time.