Hello
I am listening classical music, and once I had same question like you, I ended up buying it and now after probably 5 month I can say:
1. On normal listening volume you can hear 60Hz-12kHz range, (I tested it on sine wire sound producing program) if you play 15Khz sound you will hear nothing
2. It performs awfully large orchestra and violin compositions
3. It could be good for solo Cello, Brass, and guitars. (if recording is good)
4. If you listen Jazz also performance
exceeds expectations
5. I never owned such worst headphone for female opera songs
Burning helps (perhaps). Yes mid bass is not well defined and overpowered, Example: listening Carmen by Bizet you will notice that drums are somewhat not as it should be. Lot of people talking about need of amplification BUT my experiences are different if you have new Realtec onboard sound card you would not need AMP but it helps anyway.
So if you have only 77-84 $$ it is normal headphone
MalVeauX member of this community recommended me Audio-Technica TAD400/500 series, probably it is better but I never tried it myself.
I don't know what headphone you owned in past, so probably you will be disappointed on first listening experience.
Happy listening
Lumos