Artificial Harmonics
The tern artificial harmonic is a bit of a misnomer, they are still harmonics, but the artificial aspect of it is based on the fact a guitarist is fretting the string and artificially changing the fundamental note of the string. A guitarist familiar with natural harmonic node placement will already be familiar with what is going on with the string itself to create the harmonic sound. However, artificial harmonics are generally performed so differently from natural harmonics that it is useful to consider them two different techniques entirely, even though the way they produce the harmonic sound is basically the same.
Natural harmonics are fairly easy once you know where the nodes are located and have some practice with them. However, since the fretting hand is fretting the notes, and no longer available to activate the harmonic node, and the node locations change for every fret, artificial harmonics are much more difficult to work with. The advantage to using artificial harmonics is that you are no longer limited to a handful of notes, which may or may not be useful in a particular key, but it will take more time and practice than natural harmonics to actually learn to do consistently.
The example below is a line more typical of a method of playing artificial harmonics that is sometimes referred to as harp harmonics. The fretting hand frets the indicated note on the tab, while either the index or middle finger of the picking hand is outstretched to lightly touch the string at the node located above the fret indicated above the score. Remember, like a natural harmonic, you aren’t fretting at the node, you just need to lightly touch the string.

The above example activated the relative same node, the node that divides the string and half and raises the string pitch up an octave. Even though it is the same type of node, each fret locates this node in a different spot. An easy rule of thumb to figure out where the nodes are is to just add the fret location of the desired node type to the fretted node location (so the halfway node located at the 12th fret of the natural harmonic is located at the 17th fret for the artificial harmonic of the 5th fret). This is fairly useless once the nodes rise above the 24th fret and for most pinch harmonics, but it is a decent starting point.
The harp harmonic method shown above usually is not very good for adding fast, short harmonic notes to lines that are still mostly regular notes. The hand positioning for it requires too much movement in faster passages, but it is useful for slower passages that require very particular harmonic notes to be activated.
Pinch harmonics is the more common method for throwing artificial harmonic notes into solos, though how often this appears in rock solos varies more based on the guitarist than the style of music. Playing these require touching the node with the thumb of the picking hand while the string is plucked (most people tend to overlook that you still are hitting the node, but that is why hitting the string in different places with the thumb produces different harmonics). The only way to get good at this technique is to practice it. Just fret a note and keep plucking the string until you find the node and get it to ring clearly.
The issue with this technique is that many guitarists hold the pick slightly differently and pinch harmonic nodes are generally higher than the highest fret on the guitar. Since there is no relative way to show where the node is and the way the strike approaches differs from one guitarist to the next, you do need to practice this and find what works for you. This can be a difficult technique to start practicing, but once you start getting clean harmonics using it, it becomes much easier.
Keep on rockin'!

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