Many modern ensembles which specialize in the performance of Baroque music have agreed on a standard of A = 415 Hz. An exact equal-tempered semitone lower than 440 Hz would be 415.30 Hz; this is rounded to the nearest integer. In principle this allows for playing along with modern fixed-pitch instruments if their parts are transposed down a semitone. It is, however, common performance practice, especially in the German Baroque idiom, to tune certain works to , approximately a semitone higher than 440 Hz (460–470 Hz) (e.g., Pre-Leipzig period cantatas of Bach).