tremolos

Tremolo refers to two related musical effects that share a common goal of producing rapid fluctuation. In its most basic sense, tremolo means a rapid repetition of a single note or a rapid alternation between two neighboring pitches. The term is also used for a timbral or amplitude modulation produced by a device or electronic signal.

In notation, tremolo is indicated by strokes drawn between the stems of two notes or by beams crossing a single note. Measured tremolo specifies a definite subdivision (for example, the repeated notes fill the note’s written value), while unmeasured tremolo gives no exact rhythm and is resolved by the tempo or the performer’s discretion.

On bowed string instruments, tremolo is typically realized as rapid, even bowing. A single pitch can be tremoloed to sustain the note, or two pitches can be alternated to create a shimmering texture. In orchestral writing, tremolo helps sustain notes or intensify passagework without resorting to longer, tied values.

In guitar playing, tremolo can mean tremolo picking—rapidly repeating a single note—or the use of a tremolo arm (whammy bar) to modulate pitch. In electronics and recording, tremolo describes amplitude modulation, often produced by low-frequency oscillators in amplifiers and synthesizers, yielding a pulsating loudness.

Historically, tremolo appears in Baroque and later repertoire as tremolando figures for strings, with later composers expanding the technique for dramatic effect. The terms tremolo, vibrato, and trill reflect different kinds of fluctuation (repetition, pitch deviation, or alternation), and their usage varies by instrument and tradition.