Identifying A440 vs A415 and knowing baroque temperaments are completely different skills. A415 is about a half step below A440, but without absolute pitch you

Identifying A440 vs A415 and knowing baroque temperaments are completely different skills. A415 is about a half step below A440, but without absolute pitch you can't really tell. Tuning is mostly about counting the beat frequency between overtones of two notes in an interval, and then you sort of learn the "color" of the exact interval. Things like equal tempered fifths and the Werckmeister F4-A4 third become pretty recognizable when you know them.