Editing Harmonica (section)

==Techniques==
{{Main|Harmonica techniques}}

'''Vibrato''' is a technique commonly used while playing the harmonica and many other instruments, to give the note a 'shaking' sound. This technique can be accomplished in a number of ways. The most common way is to change how the harmonica is held. For example, the vibrato effect can be achieved by opening and closing the hands around the harmonica very rapidly. The vibrato might also be achieved via rapid glottal (vocal fold) opening and closing, especially on draws (inhalation) simultaneous to bending, or without bending. This obviates the need for cupping and waving the hands around the instrument during play. An effect similar to vibrato is that of the 'trill' (or 'roll', or 'warble, or 'shake'); this technique has the player move their lips between two holes very quickly, either by shaking the head in a rapid motion or moving the harmonica from side to side within the embouchure. This gives a quick pitch-alternating technique that is slightly more than vibrato and achieves the same aural effect on sustained notes, albeit by using two different tones instead of varying the amplitude of one.

In addition to the 19 notes readily available on the diatonic harmonica, players can play other notes by adjusting their [[embouchure]] and forcing the reed to resonate at a different pitch. This technique is called '''bending''', a term possibly borrowed from guitarists, who literally bend a string to subtly change the pitch. Bending also creates the glissandos characteristic of much blues harp and country harmonica playing. Bends are essential for most blues and rock harmonica due to the soulful sounds the instrument can bring out. The "wail" of the blues harp typically requires bending. In the 1970s, [[Howard Levy]] developed the '''over bending''' technique (also known as "overblowing" and "overdrawing".) '''Over Bending''', combined with bending, allowed players to play the entire chromatic scale.

In addition to playing the diatonic harmonica in its original key, it is also possible to play it in other keys by playing in other "positions" using different keynotes. Using just the basic notes on the instrument would mean playing in a specific mode for each position. For example the Mixolydian mode (root note is the second draw or third blow), produces a major dominant seventh key that is frequently used by blues players because it contains the harmonically rich dominant seventh note, while the Dorian mode (root note is four draw) produces a minor dominant seventh key. Harmonica players (especially blues players) have developed terminology around different "positions," which can be confusing to other musicians, for example the slang terminology for the most common positions (1st being 'straight', 2nd being 'cross', 3rd being 'slant', etc.).

Another technique, seldom used to its full potential, is altering the size of the mouth cavity to emphasize certain natural [[overtones]]. When this technique is employed while playing chords, care must be taken in overtone selection as the overtones stemming from the non-root pitch can cause extreme dissonance.

Harmonica players who amplify their instrument with microphones and tube amplifiers, such as blues harp players, also have a range of techniques that exploit properties of the microphone and the amplifier, such as changing the way the hands are cupped around the instrument and the microphone or rhythmically breathing or chanting into the microphone while playing.