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F-double sharp


Sol, So, or G is the fifth note of the fixed-Do solfège starting on C. As such it is the dominant, a perfect fifth above C or perfect fourth below C.

When calculated in equal temperament with a reference of A above middle C as 440 Hz, the frequency of Middle G (G4) note is approximately 391.995 Hz. See pitch for a discussion of historical variations in frequency.

It has enharmonic equivalents of Fdouble sharp (a diatonic semitone below G) and Adouble flat (a diatonic semitone above G).



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