Audio: repeat (0:03)
repeat plays repeat notes on a cello. The repeat figure shows the score consists of a single repeated note, the note D. It is played on the open D string of the cello, and the D an octave above and the D an octave below.
The simplest way to move between two notes in a melody is to move to the same note again, repeat it, in other words.
A repeat note is an enigma. It is an extremely effective and simple tool for emphasising a significant change in a melody, however, there is no motion, the note is not moving relative to anything other than itself. It is the greatest discontinuity in a melody. A repeat note is far more disconcerting than any other type of motion because the listener has absolutely no idea what is going to happen next. It destroys all sense of movement and with it the notion of scale and key. All that remains is a solitary note. That is why a repeat note, and its close relation, the drum roll, is used to convey tension and excitement and build up an atmosphere of anticipation.
It does not take long for a repeat note to destroy the sense of motion in a melody. We already know that a listener has difficulty perceiving a rhythm when the gap between successive beats is more than 2 seconds. It seems reasonable to assume that a note repeated for longer than 2 seconds will begin to destroy the perception of key. This is not long, the equivalent of one bar of music in 4/4 meter at a tempo of 120bpm.
A note does not have to be repeated in unison, it can be repeated an octave above or below. Repeating a note at the octave is a way of partly avoiding the disorienting effect of a repeat unison.
A repeat note is used to good effect as a drone in harmony. A repeat note in a solo melody should be used sparingly, last less than a couple of seconds, and display a prominent government health warning at all times.