Parallel and counter parallel

In music, a parallel chord (relative chord, German: Parallelklang) is an auxiliary chord derived from one of the primary triads and sharing its function: subdominant parallel, dominant parallel, and tonic parallel. The term is derived from German theory and the writings of Hugo Riemann (see: Riemannian theory).

The substitution of the major sixth for the perfect fifth above in the major triad and below in the minor triad results in the parallel of a given triad. In C major thence arises an apparent A minor triad (Tp, the parallel triad of the tonic, or tonic parallel), D minor triad (Sp), and E minor triad (Dp).

For example, the major  tonic  and  tonic parallel  and minor  tonic  and  tonic parallel .

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