Richter tuning

Richter tuning is a system of choosing the reeds for a diatonic wind instrument (such as a harmonica or accordion). It is named after Joseph Richter, a Bohemian instrument maker who adopted the tuning for his harmonicas in the early 19th century and is credited with inventing the blow/draw mechanism that allows the harmonica to play different notes when the air is drawn instead of blown.

Richter tuning is designed as a compromise between diatonic melody and harmony. The lower portion of the harmonica is designed to play the tonic and dominant chords on the blow and draw respectively (in the key of C, this would be the C major and G major chords). The remainder of the instrument is tuned to, in this example, blow entirely in the key of C major, with each successive note following the sequence

and the four notes not in the C major chord arranged on the draw in the sequence

For example:

There have been many variants of Richter tuning.

Country tuning raises the initial F by a semitone to an F♯. This primarily aids in harmony in the key of G, facilitating easy play of the G-C-D (I-IV-V) chord progression, while maintaining a partial G7 (minus the root) higher on the harmonica. It can occasionally be helpful in some melodies, most notably "The Star-Spangled Banner," which has a low F# and a high F. For example:

(Compare this to major seventh tuning, below.)

Harmonic minor tuning is a variation in which E is replaced by E♭ and A is replaced by A♭. Thus the blow notes repeat a sequence of

(perhaps shifted to begin with E♭ or with G) and draw notes at some point begin to follow a repeating sequence of

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