The separation between vocal and music is good. Vocal sounds solid but need more details. Base is good with right delay. Overall performance is excellent. However there are room for improvement in terms of the cable design. There are noise coming from cable when it get contact with anything. The cable is too short.
I have to say the ie600s are fantastic ear buds however they perform at their best when used with a DAC and of course using hi res files. The sound is simply outstanding no regrets what so ever. Please note the sound is still 8 out of 10 through a smartphone. When connected via a decent DAC and using the 4.4 balanced cable supplied honestly 10/10....Thankyou Sennheiser!!