Let us consider a standard classical guitar with only 19 frets and 6 strings being played with the standard tunning E2-A2-D3-G3-B3-E4.
In this configuration, the classical guitar has a 'normal' playing range spanning the notes E2 - B5, comprising, thus, 3.5 octaves + 0.5T = 43ST -> 44 notes (T = tone and ST = semitone). This is exactly half of the playing range A0 - C8 of a standard piano with 88 notes.
The highest 'normal' note playable on top of the guitar fingerboard is B5 (19th fret of the 1st string). However, which is the actual highest note achievable on the classical guitar?
If we consider natural harmonics, by playing it on the 5th fret of the 1st string (or a little past half of the guitar's sound hole), one reaches E6, which is 2.5T above B5 (this E6 can be played as a 'normal' note on the 24th fret of the 1st string of an electric guitar).
If we consider artificial harmonics, it is not clear for me if one can produce clearly audible notes above E6. What do you know about it?
However, I was testing something unusual, and it is possible to go above E6 by playing on the 'wrong' side of the classical guitar neck. For instance, if one presses the 8th fret of the 1st string with any finger of the left hand and plucks the string with any finger of the right hand on the 'wrong' side of the guitar neck, it seems to me that B5 is produced. If one keeps doing the same thing but pressing the 1st string on the 7th fret, 6th fret, and so on, the notes produced become higher and higher. The last clearly audible note reached in this scheme, and the highest note I found on the classical guitar, is produced by doing the above technique with the 3rd fret of the 1st string pressed. However, I did not know by ear which note was this (it seems to me that the notes produced with this 'reversed guitar neck technique' do not walk in intervals of 1ST). By using the online note identifier https://www.flutetunes.com/tuner/ the program clearly identified this note as G7 (it is, therefore, 3 octaves above the 'normal' G4 of the 3rd flet of the 1st string, which is produced by playing on the usual side of the guitar neck)!
Does anyone know anything about the dynamics of the notes generated with this 'reversed guitar neck technique'? Any references about it?
And which is the highest note that you are aware of that can be played on a standard classical guitar with standard tunning?