The passamezzo antico is a ground bass or chord progression that was popular during the Italian Renaissance and known throughout Europe in the 16th century.van der Merwe, Peter. 1989. Origins of the Popular Style: The Antecedents of Twentieth-Century Popular Music, p.207. Oxford: Clarendon Press. . The progression is a variant of the double tonic: its major mode variant is known as the passamezzo moderno.
The sequence consists of two phrases as follows: (For an explanation of this notation see Chord progression)
i bVII i V III bVII i V i
Though usually in the key of G minor, in the key of A minor this gives:
Am G Am E C G Am E Hm
The romanesca is a variant of the passamezzo antico, where the first chord is the III (e.g., a C major chord in A minor). A famous example is "Greensleeves".
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