Coupling

(Ger. Koppelung, Oktavkoppelung).

In Schenkerian analysis (see Analysis, §II, 4), a method of Prolongation involving the linking of two registers separated by one or more octaves. The two registers are not sounded simultaneously, but are ‘coupled’ by movement from one to the other and back again. At a primary structural level, coupling reinforces movements in the Obligatory register of the Urlinie, i.e. the prevailing octave of the fundamental upper voice.

At later levels, that is, towards the musical ‘foreground’, coupling enables the composer to abandon a register while fulfilling some other task elsewhere. Ex.1 shows one of Schenker’s favourite examples of coupling in the bass voice, the last six bars (bars 98–103) of the slow movement of Beethoven’s Sonata in D minor op.31 no.2 (Der freie Satz, 1935, fig.108/2): the B' at the beginning of this passage, which is picked up by the B' at the end (note Schenker’s exclamation mark), is coupled to the B in bars 100–02, which supports a more delicate contrapuntal design. Coupling is indicated here by the straight lines joining the Bs in the two registers.

As coupling involves the linking of octave registers, it may be thought of as a synthesis of two closely related methods of prolongation, namely, ascending and descending Register transfer.

WILLIAM DRABKIN