Left hand technique

The fingers of the left hand press on the strings to shorten their effective length and change the pitch of the notes that the right hand plays. In musical notation the fingers are referred to as 1-4 from index to little fingers. The basic position for the left hand is much the same as that of the right, except upside down. Unlike many players of steel-string and electric guitars, which have narrower neck and fingerboards, the classical guitarist does not place her or his left hand thumb over the top of the neck, instead placing it directly behind the neck, usually opposite the second finger.

To play a note cleanly the fingertips of the left hand should be pressed against the string just behind (to the headstock side of) the appropriate fretwire. Often the left hand fingers are all required at once and many (sometimes awkward) hand positions are necessary. Chords requiring all six strings usually employ the barre technique. The guitarist places the first finger across all of the strings at a particular fret and uses the remaining three fingers to play other notes.

When playing notes on the treble strings above the twelfth fret (where the shoulders of the guitar meet the neck) the left shoulder is dropped down a little and the thumb is placed on the underside of the fingerboard to the left of the other fingers. For example if the middle finger is playing an F# at the fourteenth fret of the first string the thumb would be pressing upwards somewhere near the eleventh fret.

One and the same note can be played on different strings: this is possible since the vibrating part of a string can be shortening (higher pitch) or lengthened (lower pitch) by pressing the string against the correct fret with a left-hand finger.

The guitarist often has a choice here:

  • Using a manageable left-hand fingering that is not too difficult. (Often fingerings at a higher or lower fret-position (on other strings) might simplify the flow and progression of left-hand fingerings)
  • Using a left-hand fingering so that the notes are played on strings with the desired timbre/tone (the same pitch played on different strings has different timbre/tone due to the characteristics of the string)
  • Choosing a left-hand fingering in such a way that a voice on a string is kept vibrating for its duration: without stopping it too early due to another note played on the same string.
  • Compromising this duration if the left-hand fingering would otherwise be too difficult (e.g. in transcriptions): compromising it in the best way possible (e.g. if possible fretting/pressing (without plucking it) a lower, harmonically related note on a currently unused string, so that it vibrates in resonance, even when the actually plucked note/voice is stopped early due to the fretting of another note on the string).

Slurs

Slurs, trills and other ornaments are often played entirely with the left hand. For example; in a simple case of an ascending semitone slur (Hammer-on), a note stopped by the first finger of the left hand at the fifth fret is first played in normal manner, then, without the right hand doing anything further, the second finger of the left-hand is placed straight down at the sixth fret on the same string, using its momentum to raise the tone of the still-ringing string by a semitone. A descending slur (Pull-off) is simply the opposite of the above, the slur begins on the higher note and it is common that the finger pressing the higher note actively plucks the string as it lifts, causing the string to vibrate from the fret that the lower finger is depressing. The lower finger is usually in position and pressing before the procedure begins. Three specific descending slurs exist, (1) the active finger lifts directly up and off the string, (2) the active finger rests against the adjacent string immediately after, and (3) a hybrid of these two in which the finger bumps the adjacent string before lifting off.

If these procedures are repeated a few times the result is known as a trill. Because the note is being plucked repeatedly it is possible to continue a trill indefinitely. Often the upper note in such a trill is played by alternating fingers thus: 2-1-3-1-2-1-3-1...

Vibrato

Vibrato is possible with a classical guitar by pulling the left hand finger back and forth horizontally (i.e. along the string axis, and not across it as for a "bend" in rock or blues music) producing a subtle variation in pitch, both sharper and flatter than the starting note, without noticeably altering the fundamental tonal focus of the note being played. When vibrato is required at the first or second fret it is sometimes beneficial to push the string across its axis as it produces a more noticeable vibrato sound there. This second method will only vary the pitch by raising it sharper than the starting note which is the most common method of vibrato used by steel string and electric guitar players.

Harmonics

Natural harmonics can be played by touching a left hand finger upon specific points along an open string without pressing it down, then playing the note with the right hand. The positions of both the left and right hand are important. The left hand must be placed at a nodal point along the string. Nodal points are found at integral divisions of the string length. The simplest example would be when the left hand finger divides the string in two and is placed at the twelfth fret. The note then played is one octave higher than the open string. If the string is divided in three (left hand finger near the seventh fret) the note played is one octave and one fifth above the open string. The player must be careful not to pluck the string at another node (nearer the bridge) otherwise the harmonic will not sound. This can be easily demonstrated by resting a left hand finger on the fifth fret and trying to play the note by plucking the string at the twelfth fret with the right hand - no note will be produced. Ideally the right hand should pluck the string at an antinode.

Artificial harmonics are played by stopping the string as usual with the left hand then resting (not pressing) the index finger of the right hand on the string at a nodal position (commonly 5, 7, 9, or 12 frets above the left hand finger) and plucking the string with the ring finger or thumb of the right hand.

Left hand positions

In common with other classical stringed instruments, classical guitar playing and notation use formal positions of the left hand. The 'nth position' means that the hand is positioned with the first finger over the nth fret.