mrbunny, Aug 2, 2015 : I suppose it will all come down to quality once it arrives. I noticed massive difference between my Z3 and my Nexus 6 (Z3 takes it!)[/QUOTE] I just compared my Moto X 2nd Gen (i believe uses same audio chip as the Nexus 6) to the OP1 audio quality using the same song and my RHA T20. The Moto X is louder which, means it has a more powerful amplifier but the sound was not as good just louder, the bass was not as deep and the trebles were less controlled and the mids less defined. When i plugged in my OP1 the sound quality was definitely better although not as loud on maximum volume. The RHA T20 are an amazing pair of earphones and definitely sound better on the OP1. So the OP2 will sound better than your Nexus no doubt but i will be surprised if they will sound better than your Z3 because Sony are known for using top quality DAC's in their phones. That is the best i can do until i get the OP2 to test.