The difference, in short, is because one of the ensembles is using historical tuning practices. The modern pitch standard is A440, meaning that A4 (the A above middle C) is 440 Hertz.
The difference, in short, is because one of the ensembles is using historical tuning practices. The modern pitch standard is A440, meaning that A4 (the A above middle C) is 440 Hertz.