A Dictionary of Music and Musicians/Mixed Cadence
MIXED CADENCE. The two most distinct and obvious forms of cadence are such as are formed either by the succession of dominant or of subdominant and tonic harmony, and these are respectively called Authentic and Plagal cadences. The term 'Mixed' has been applied to a cadence which is in some senses a combination of these two forms, by having both subdominant and dominant harmony in close juxtaposition immediately before the final tonic chord, by which means the tonality is enforced both by the succession of the three most important roots in the key, and also by giving all the diatonic notes which it contains.
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