Timpani roll
A fast, even drumming on the timpano.
What it means
The timpani roll is a fast sequence of alternating single strokes of both hands, executed so densely that no single stroke can be heard out anymore and a continuous, sustained sound results. Because the timpano has a definite pitch, a held note results that can be freely shaped in volume — from barely perceptible to great force. Unlike with the snare drum, the timpani roll works with single strokes, not with the rebound of double strokes.
In the notation
The roll is written as a note with tremolo strokes on the stem, usually tied over the desired duration. Dynamic markings and hairpins for swelling and diminishing stand below it and are especially important here, because the roll serves above all as a dynamic device. For very short rolls, some scores notate the number of strokes more precisely, to indicate the density.
Musical use
The roll is one of the most effective means of intensification in the orchestra: it can grow out of silence, hold a tension over many bars, and lead into a climax. Equally it serves as a quiet, barely audible foundation that carries a passage without pushing itself into the foreground. Since the nineteenth century it has belonged to the fixed stock of orchestration, often under sustained string or wind chords. Because it carries the pitch along, it reinforces the harmony as well as the tension.
Performance practice
Practise the roll first slowly as an even alternation of single strokes and increase the speed only once both hands sound the same; unevenness stands out more than slowness. The necessary density depends on the pitch — low timpani need fewer strokes than high ones. Keep the striking point constant, about a hand's width from the edge, and work with soft mallets for quiet passages, harder ones for loud ones. Begin a swell with very small movements close to the head. Plan the ending precisely: a roll that frays ruins the effect.
Adjust this instead of rolling at the same speed everywhere. Keep the striking point constant. Plan the ending precisely, because a fraying roll destroys the effect, and coordinate the course with the conductor.