I agree with you on the sibilance and difficulties with female vocals. I do think the issue with my HE6SE is that it is more pronounced to me. My HEX V2, HE-500, and the HE-6 I have access to all have ringing issues in the 8-10 kHz areas, but none has a spike of such severity as the HE6SE centered at 3.8 kHz. Those other cans are all excellent for female vocals. For $699 brand new I shouldn't complain, just listen to music w/o female vocals - except that's about 40% of my listening.
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