A flat
The equivalent of an f sharp is a G flat.
A double sharp is the enharmonic of B nature
It's called enharmonic spelling. An example is C-sharp and D-flat.
Just as G sharp is one semitone above G, and G double sharp is two semitones above G, G quintuple sharp can be found five chromatic semitones--equal in twelve-tone equal temperament to a perfect fourth--above G natural. G quintuple sharp is enharmonic to A triple sharp, B sharp, and--most notably--C, as well as D double flat, E quadruple flat and F quintuple flat. On a piano, this note can be played by striking the white key immediately on the left of a pair of black keys. Triple sharps, triple flats, quadruple sharps and the such are very rarely encountered, and so the inability to play a quintuple sharp on the piano will not severely disadvantage one. Wherever did you come across this one?
No. It would be F#X or Bb bb. (F sharp double-sharp or B flat double-flat.)
G sharp (enharmonic A flat).
F sharp is the enharmonic.
F sharp is the enharmonic.
The enharmonic equivalent to A-flat is G-sharp; The enharmonic equivalent to G-flat is F-sharp.
Yes.
The equivalent of an f sharp is a G flat.
G double sharp is a very clumsy way of saying (enharmonically) "A natural".
A flat. Because this note is between G and A, you can go up from G (make it a sharp) or down from A.
G sharp (enharmonic A flat).
A double sharp is the enharmonic of B nature
Enharmonic
Yes, that would be F♯x (F triple sharp) - enharmonic with G sharp.