Absolutely stellar. They are arguably one of the best all-around IEM's ever made. They make you want to listen to music. Listening sessions turn into epic, hours long, musical journeys. You just get lost in the beautifully balanced sound. The bass is to die for. Not "Bass Head" but when the music calls for head crushing notes, they deliver with enthusiasm. Wide, holographic soundstage. I could go on raving for days. No matter your favorite genre of music, you will not be disappointed. HIGHLY recommend the KK. If you like IEM, these are a must-have in your collection. For most, these could be end-game IEM.