Retrograde

What it means

Retrograde designates the transformation of a pitch sequence in which it is read from back to front. In German this procedure is called Krebs or Krebsgang (crab or crab motion), after the proverbial backward movement of the animal. The notes stay the same, their order is reversed; intervals correspondingly appear in reversed direction.

Musical use

The retrograde belongs among the four basic shapes that can be derived from a pitch sequence: the original, the inversion, the retrograde, and the retrograde inversion. Of these it is the hardest for the ear to recognize as a derivation, because melodic shape arises above all from forward motion — a melody read backward usually sounds like a new one. In the notation, by contrast, the relation is easily demonstrated.

In the artful polyphony of the late Middle Ages and the Renaissance, the retrograde appears in canons, in which one voice sings the same line as the other but backward, and in riddle canons, in which the instruction to read backward is encoded. In the Baroque, too, the procedure belongs to the stock of contrapuntal arts. Larger forms can be laid out as a whole in crab fashion, so that the second half repeats the first backward; this touches on the arch form.

In the twentieth century the retrograde became, in twelve-tone technique, one of the four basic forms of the row and thus a regularly used procedure.

The retrograde is to be distinguished from the inversion, in which the order stays and the direction of the intervals is mirrored, and from the retrograde inversion, which combines both.

In twelve-tone technique, the retrograde is one of the four basic shapes of the row. In older music it appears as a display piece, for instance in crab canons, in which one voice sings the other backward. Because hearing a backward-led line is difficult, the retrograde often remains more a construction than an immediately audible event.

Performance practice

If you look for retrograde forms in a piece, rely on the notation rather than on your ear. Shape retrograde lines as a musical shape of their own with its own course. And with crab canons, take care that both voices remain equally distinct.