-
And the video that @Pinski posted contains the explanation for that 1st Formula:
The natural musical alphabet consists of whole steps and half Steps
A w B h C w D w E h F w G (B&C, E&F are critical pairs, only 1/2 step apart)
In those intervals with the ‘w’ you find your “accidentals” or sharps/flats resulting in the 12 notes of the musical alphabet or chromatic scale.
A – A# – B – C – C# – D – D# – E – F – F # – G – G#
I put dashes in there so that they remained spaced after posting)
Note that A# is also Bb C# is also Db, etc.What naturally flows from all this is the second Fretboard Formula:
“The octave of each note is 12 frets higher on the same string,
A appears again, after the G# the next fret is an A, one octave higher than the open string.