Timbre & Articulation

A near-field photograph of Lizzo playing a flute which is made from patterned crystal with metal joints in one of the holding rooms at the Library of Congress. American singer/songwriter Lizzo performs a crystal flute constructed in 1813 at the Library of Congress in Washington. Unlike contemporary flutes built from wood and ivory, the sound of crystal flutes — and the metal flutes that eventually replaced them — was not susceptible to changes in temperature and humidity.
(Library of Congress | Public Domain)

While we often consider pitch and volume to be fundamental characteristics of a note, there are other characteristics that play a large part in musicality and expression.

Timbre

Timbre — a French term, pronounced "TAM-burr" — is a difficult concept to describe, but one that most people easily recognize: it is the characteristic that differs between notes played by different instruments, such as a bassoon and a cello, even if they are playing the same pitch at the same volume. This quality is sometimes also referred to as tone color.

Figure 1: Losing My Religion, a 1991 song by the American group R.E.M.. The song's texture features band member Peter Buck playing both electric guitar and mandolin, and guest musician Peter Holsapple playing acoustic guitar: three similar instruments which unique timbres.

The Harmonic Series

One factor that influences a sound's timbre is the presence and relative strength of different simultaneous frequencies within the sound. When a particular note is played on an instrument, the vibrating medium creates sound waves at that note's frequency, called the fundamental, but also at frequencies which correspond to divisions of the medium's length — at half of the frequency, a third of the frequency, a quarter of the frequency, and so on. These additional pitches are called overtones, and the spectrum of divisions of a particular frequency is called the harmonic series.

Figure 2: A tone and its first eight overtones, showing a portion of the harmonic series. Adding overtones to a tone is one way of altering a tone's timbre.

The characteristics of an instrument, such as the material from which it is made and the shape of its resonating chamber, cause certain overtone wavelengths to be reinforced and others to be suppressed. The combination of these waveforms often change the shape of the combined waveform in interesting ways which are portrayed through the timbre of the sound produced.

Figure 3: Oscilloscopes portray sound as waveform diagrams, showing time on the X axis and amplitude on the Y axis.

Noise

Another factor influencing timbre is the level of pitch and volume control imposed on particular sound waves. While a trombone can produce a sound for which the pitch and timbre are very strictly controlled, the sound waves produced by a snare drum are much more sporadic and chaotic, producing a fuzzy, unpitched sound. This quality of sound is called noise and is an important timbral characteristic of sounds which are "breathy," warm, or sibilant.

Articulation

The articulation of a sound describes the sound's shape over time. Vocal music and speech is articulated by parts of the mouth: lips, teeth, tongue and throat. Acoustic instruments can articulate notes through various means, including fingering, tonguing, and other methods.

A photograph of Brian Rosenworcel performing seated at a drum kit. The kit consists primarily of hand drums -- bongos, congas and a tambourine -- as well as a snare drum with a leather covering and some smaller cymbals, and Rosenworcel is singing while playing with his hands rather than drumsticks.
Figure 4: American drummer and singer/songwriter Brian Rosenworcel performing as part of the band Guster. A unique aspect of the band's texture is Rosenworcel's use of hand drums rather than a traditional drum kit played with drumsticks.
(Tammy Lo | CC BY-2.0)

While it is often considered a separate characteristic, articulation is usually a factor of volume, describing how quickly sounds transition to and from silence, and how their volume changes over the duration of the note.

Attack and Release

The speed and force with which a sound begins is referred to as the sound's attack. Some instruments, like marimba, have a very fast and forceful attack, while woodwind instruments like flute and saxophone are capable of slower, gentler attacks.

Similarly, the end of a sound is called the sound's release. Pipe organs have an immediate, sudden release, where the sound immediately ceases when the key is lifted. Gongs and cymbals tend to have long releases, requiring players to deliberately stop the sound by dampening the instrument with their hands.

Sound Shaping

Articulation also describes the ways which musicians shape the middle part of a sound. Accented notes are performed with an additional burst of volume at the beginning of the sound which quickly decreases to a sustained level. Longer notes are often shaped expressively with crescendos and diminuendos that help give music a sense of feeling and forward movement.

Wind players and string players usually shape notes with vibrato, a slight, cyclic variation of pitch that gives the sound a feeling of movement and vitality.

A photograph of Vienna Teng, seated at a grand piano on stage and singing into a microphone.
Figure 8: American singer/songwriter Vienna Teng performing in Norfolk, Connecticut in 2009. Singers often shape vocal tone by moving their diaphragm. While this technique is referred to as vibrato, it is technically tremolo, a slight wavering of volume rather than pitch.
(Michael Curry | CC BY-NC-2.0)

Timbre & Articulation: Summary

  • Timbre is the characteristic of sound that varies among different instruments, and is often also called tone color.
    • Timbre can be affected by the presence of specific overtones: frequencies which are multiples of a given pitch's frequency.
    • The spectrum of divisions of a particular frequency is called the harmonic series.
    • Timbre can be affected by the presence of noise, sounds which result from uncontrolled, random sound waves.
  • Articulation refers to how a sound's volume changes over a short period of time, often referred to as the sound's shape.
    • Instruments can articulate sounds through fingering, tonguing and other methods.
    • The speed and force with which a sound begins is called the sound's attack.
    • The speed at which a sound stops or fades is called the sound's release.
    • In addition to the beginning and ending of a sound, a held sound can change in volume as in crescendos and diminuendos, or waver slightly as in vibrato.

Exercises