TRUE - “Sincerely” from Violet Evergarden. The s- and t-sounds in that song are crazy difficult to control and they can sound sibilant really easily on less than ideal headphones. If the headphones’ got spicy treble? This song will literally kill your ears. If the headphone has excellent high frequency control and can tame the harshness of those S-sounds? The song will sound amazing. This song is what I use to test headphones, because if it sounds sibilant or harsh, instant disqualification.

Headphones that have passed the test: Denon D7200, Sennheiser HD660s, etc