Cross relation is a music theory term used to describe the clash between two notes in different voices or parts of a composition. This clash occurs when a note in one voice is followed by or played simultaneously with its chromatic altered form in another voice. In simpler terms, cross relation is the dissonance created when a note and its chromatic alteration are played together.

What Is Chromatic Alteration?

Chromatic alteration refers to the modification of a note by changing its pitch through the addition of sharps, flats, or natural signs. For example, if we take the note C and add a sharp sign to it, it becomes C#.

Similarly, if we add a flat sign to it, it becomes Cb. Chromatic alteration can also be applied to intervals, chords, and scales.

Examples of Cross Relation

One common example of cross relation occurs in Baroque music where the leading tone (seventh scale degree) is raised by half step in one voice while being lowered by half step in another voice. This creates a clash between the two voices due to the chromatic alteration of the leading tone.

Another example is found in hymns where an ascending melody contains both natural and sharpened versions of the same note. For instance, if one part sings an A while another part sings an A# immediately after it, this creates cross relation.

How Do Musicians Deal With Cross Relation?

Musicians have various ways of dealing with cross relation depending on the context and style of music being played. One approach is to simply avoid using cross relations altogether. This can be achieved by choosing different notes that do not create dissonance when played together.

Another approach is to use cross relation intentionally as a compositional tool to create tension and release within a piece of music. This technique can be particularly effective when used sparingly and in the right context.

Conclusion

In conclusion, cross relation is a musical term used to describe the clash between two notes in different voices or parts of a composition. It occurs when a note and its chromatic alteration are played together.

Musicians can deal with cross relation by avoiding it altogether or using it intentionally as a compositional tool. Understanding cross relation can help musicians create more interesting and complex pieces of music while also avoiding unwanted dissonance.