Musical Slurs: Meaning and Performance Across Instruments

In Western musical notation, a slur is a curved line that embraces a group of notes, signaling to the performer that these notes should be played without separation. This technique is known as legato articulation, a style of playing where notes flow smoothly into one another without audible gaps.

Visually, the placement of the slur depends on the direction of the note stems: the curved line is generally placed over the notes if the stems point downward, and under the notes if the stems point upward.

Key Facts

• Primary Purpose: Indicates legato performance and helps delineate the extent of a phrase line.
• Visual Marker: A curved line placed above or below notes depending on stem direction.
• Instrument Variation: The physical execution of a slur varies significantly between strings, winds, keyboards, and voices.
• Extreme Notation: Very long slurs may be used by composers to demand the maximum possible legato, even if technically difficult to achieve.

The Function of Slurs in Different Musical Contexts

Keyboard and Wind Instruments

In keyboard music, slurs serve two main roles: they define the boundaries of a phrase and indicate that melodies or arpeggiated chords should be performed legato. For woodwind and brass instruments, slurs relate to tonguing (the use of the tongue to articulate the start of a note). A slur indicates that the performer should not re-articulate each note with the tongue.

An exception exists for the slide trombone and similar slide-based instruments. Because of how pitch is controlled, certain note combinations cannot be played without tonguing unless the performer creates a glissando (a continuous slide between pitches). In these instances, "legato tonguing" is employed.

String Instruments

For bowed string instruments, a slur indicates that the grouped notes must be played in a single bow stroke. While slurs suggest phrasing, they are not always definitive phrase marks. If a composer wishes to unite several separate bow strokes into one larger melodic idea, a specific phrase mark—notated as a broken line above the passage—is used instead.

For plucked string instruments, such as the guitar, slurs indicate that notes should be played without plucking each individual string. This is achieved through techniques known as hammer-ons and pull-offs.

Vocal Music

In vocal compositions, slurs are typically used to indicate melisma, which occurs when a single syllable of text is stretched across multiple different notes.

Summary of Slur Execution by Instrument

Slur Performance by Instrument Type

Instrument Category	Performance Technique	Specific Terminology
Bowed Strings	Played in one continuous bow stroke	Legato
Plucked Strings	Notes played without individual plucking	Hammer-ons / Pull-offs
Wind/Brass	Played without re-articulating each note	No tonguing (or legato tonguing)
Voice	Multiple notes sung to one syllable	Melisma
Keyboard	Smooth transition between notes/chords	Phrase delineation

Frequently Asked Questions

What is the difference between a slur and a tie?

While they look similar, a tie specifically combines adjacent notes of the same pitch into one single, longer note, whereas a slur connects notes of different pitches to be played legato.

How do I know if a slur is placed above or below the notes?

The placement is determined by the stems: if the stems point downward, the slur is placed above the notes; if the stems point upward, the slur is placed below them.

Can a slur span across multiple measures?

Yes, a slur can be extended over many notes and may encompass several bars to indicate a long, continuous musical phrase.

What happens if a slur is physically impossible to play?

In cases where a composer writes a slur that is nearly impossible to achieve technically, it serves as an instruction to perform the passage with as much legato as the instrument allows.