Single Sharps & Flats:
bA = #G
bB = #A
#B = C
bC = B
bD = #C
bE = #D
#E = F
bF = E
bG = #F
Double Sharps & Flats:
bbA = G
xA = B
bbB = A
xB = #C
bbC = bB
xC = D
bbD = C
xD = E
bbE = D
xE = #F
bbF = E
bbG = F
xG = A
xF = bA