Flutter Tongue (Flatterzunge)

What it is: Rolling a continuous "rrrrr" with the tip of the tongue while sustaining a note — like rolling a Spanish R into the mouthpiece. Some players who can't roll their tongue use a back-throat "uvular" version instead.

What it sounds like: A buzzing, growling sustain — the note is still pitched but it has a constant rapid texture overlaying it. Iconic, immediately recognizable.

When to use it: Tension, otherworldly atmosphere, modernist color, animal/insect imagery, "spooky" textures. The flute and clarinet flutter especially well; oboe and bassoon are harder. Brass also flutter, often with even more aggression.

Notation: Usually written as a tremolo (three slashes through the stem) plus the marking flz. (German Flatterzunge) or flutter.

Tip: Some players physically can't roll the front-tongue R (it's a tongue-tie thing). Always ask the player ahead of time. Don't ruin a passage by demanding it of someone who can't.

Listen:

Debussy — Prélude à l'après-midi d'un faune — the flute's languid flutter
Berio — Sequenza I (solo flute) — extreme extended-technique vocabulary
Strauss — Don Quixote — flutter tongue for the bleating sheep