Reentrant tuning

A re-entrant tuning is a tuning of a stringed instrument where the strings (or more properly the courses on coursed instruments) are not ordered from the lowest pitch to the highest pitch (or vice versa).

A break in an otherwise ascending (or descending) order of string pitches is known as a re-entry. Most common re-entrant tunings have only one re-entry. In the case of the soprano ukulele, for example, the re-entry is between the third and fourth strings, while in the case of the Venezuelan cuatro it is between the first and second strings.

Instruments often tuned in this way include:

Instruments occasionally tuned in this way include:

The tunings of coursed instruments, such as the twelve string guitar and eight string bass, are not considered re-entrant provided that the principal strings of each course are ordered from lowest to highest.