I'm a huge fan of baroque music played on original instruments. Many years ago, I conducted a small such ensemble, and we always tuned to 415 Hz. I'm quite used to that, but I would not use it outside of baroque music. Oh yeah, you can hear the difference, big time (and no, I'm not exactly a spring chicken...)
BTW, nowadays many symphony orchestras around the world tune to 442 Hz. There are some definite advantages to that, for start you get a brighter sound. Actually some of them go even higher (Berliner Philarmoniker tunes to 445 Hz.)
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