The theorbo is a string instrument played by plucking, and it belongs to the lute family. It has a long neck with a second pegbox. Like a lute, the theorbo has a curved back with a flat top, and it usually has one or three sound holes with decorative patterns called rosettes. The player uses the right hand to pluck or strum the strings and the left hand to press down on the strings to change their pitch.

The theorbo is related to other instruments such as the liuto attiorbato, the French théorbe des pièces, the archlute, the German baroque lute, and the angélique (or angelica). It is different from a regular lute because the first two strings are tuned an octave lower. The theorbo was used during the Baroque music era (1600–1750) to play accompaniment parts in basso continuo groups, which often included harpsichord, pipe organ, and bass instruments. It was also played as a solo instrument. The theorbo has a range similar to that of a cello.

Origin and development

Theorbos were created in Italy during the late 1500s. They were inspired by the need for instruments with a deeper bass range for a new type of music called opera, developed by a group known as the Florentine Camerata. These instruments were also used in musical works that included basso continuo, such as collections by Giulio Caccini. In his 1607 opera L'Orfeo, Claudio Monteverdi listed two chitaroni as needed for the performance. At first, musicians used large bass lutes with long string lengths and a special tuning method. Later, they added neck extensions and extra pegboxes to fit longer bass strings, called diapasons or bourdons, which improved sound quality and expanded the range of notes available.

The terms chitarrone and tiorba were both used to describe the instrument, but they have different origins. Chitarrone comes from the Italian word chitarra, meaning "guitar," and refers to a larger version of the instrument. The round-backed chitarra Italiana was still used, often to distinguish it from the flat-backed Spanish chitarra alla spagnola. The origin of tiorba is unclear, but some believe it may come from Slavic or Turkish words meaning "bag" or "turban."

Athanasius Kircher suggested that tiorba was a nickname in Neapolitan for a grinding board used by perfumers. It is possible that jokes about the instrument’s large size led to the nickname, which became common over time. By 1600, Robert Spencer noted confusion between the names chitarrone and tiorbo. By the mid-1600s, tiorba became the preferred name, a tradition still followed today. This helped distinguish the theorbo from other instruments like the chitarrone moderno or guitarrón. Smaller versions of the lute, with shorter string lengths, led to instruments like the arciliuto, liuto attiorbato, and tiorbino, which were tuned differently for smaller ensembles or solo performances. In basso continuo music, theorbos were often played alongside small pipe organs.

Important early composers and players in Italy included Giovanni Girolamo Kapsperger and Alessandro Piccinini. Giuliano Paratico was another early chitarrone player. In England, little solo music for the theorbo remains, but William Lawes and others used it in ensembles and operas. In France, theorbos were used in orchestral and chamber music until the late 1700s (e.g., Nicolas Hotman, Robert de Visée). Court orchestras in Vienna, Bayreuth, and Berlin still included theorbo players after 1750 (e.g., Ernst Gottlieb Baron, Francesco Conti). Music for the theorbo is written in tablature, a notation system showing which strings and frets to press.

Tuning and strings

The tuning of large theorbos includes an octave shift, called "re-entrant tuning," for the two highest strings. Composers like Piccinini and Michael Praetorius noted that metal strings (such as brass and steel) were sometimes used instead of gut strings. In Syntagma Musicum, Praetorius described the Laute mit Abzügen (or Testudo Theorbata), which had doubled strings (courses) that crossed the bridge and connected to the instrument’s base. This design differed from his Paduanische Theorba, shown in the same illustration, which had single strings. The Lang Romanische Theorba (or Chitarron) also appears to have single strings attached to the bridge. Unlike Renaissance lutes and archlutes, theorbos often used single strings for courses, though some had double strings. Most theorbos had 14 courses, but some had 15 or even 19 courses (as noted by Kapsberger).

Theorbo tuning in A is common, with modern players typically using 14-course instruments (lowest course is G). Some players tuned the theorbo a whole step lower in G. Most solo music is written for A tuning. The re-entrant tuning allowed new ways to arrange melodies and inspired a right-hand technique using only the thumb, index, and middle fingers to play chords, which Piccinini compared to a harp’s sound. The deep bass range and re-entrant strings required the bassline to sometimes be played an octave lower when accompanying basso continuo to keep the improvised chords above the bass instruments (as Kapsberger described). French music treatises also included chords where a lower note sounded after the bass when the bass moved upward. The English theorbo had only the lowest string tuned an octave lower (as noted by Thomas Mace).

Regional differences

The theorbo was created in Italy and has a long history in Italian music as both a solo and accompaniment instrument. Caccini wrote in Le nuove musiche (1602) that the theorbo was well-suited for supporting a singer’s voice because it could provide strong sound without overpowering the vocalist, marking the start of an Italian tradition of songs with a single voice accompanied by the theorbo. Italians called the theorbo’s diapasons its “special excellence.” They considered the theorbo an easier alternative to the lute because its appealing sound could mask poor playing or weak musical phrasing.

The Italian theorbo first arrived in England in the early 1700s, but a different design based on the English two-headed lute, created by Jaques Gaultier, became more popular. English theorbos were usually tuned to G and had double strings throughout, except for the first course, which used reentrant tuning. Theorbos tuned in G were better suited for flat musical keys, so many English songs and ensemble pieces written for the theorbo were in flat keys, which would be difficult to play on a theorbo tuned to A. By the 1800s, the theorbo had fallen out of favor in England because of its large size and low pitch. It was replaced by the archlute.

The first record of a theorbo in France was in 1637, and by the 1660s, it had become the most popular accompaniment instrument, replacing the 10-course lute. The theorbo was a key continuo instrument in the French court, and several French theorbo method books were published by Delair (1690), Campion (1716 and 1730), Bartolotti (1669), Fleury (1660), and Grenerin (1670). French theorbos had up to eight stopped strings and were often smaller and quieter than Italian theorbos. They had a standard length of 76 cm (30 in), while Italian theorbos ranged from 85–95 cm (33–37 in).

German theorbos are today called swan-necked Baroque lutes. In the 1600s, German theorbists played single-strung instruments in the Italian tuning transposed down a whole step, but by the 1700s, they switched to double-strung instruments in the “d-minor” tuning used in French and German Baroque lute music to avoid changing chord shapes when playing the theorbo. These instruments were called theorbo-lutes. Baron noted that “the lute, because of its delicate sound, works well in small ensembles like trios. The theorbo, because of its strong sound, is best used in large groups, such as in churches and operas.” Theorbo-lutes were likely used with Italian theorbos and archlutes in continuo settings due to the presence of Italian musicians in German courts and the need for instruments that matched the music’s key.

The theorbo reached Ukraine around 1700 and was modified with additional treble strings (called prystrunky). This version was called a torban. The Torban was mainly made and used in Ukraine, though it was occasionally found in nearby Poland and Russia.

Technique

The theorbo is played similarly to the lute. The left hand presses down on the fingerboard to change the length of the strings, which allows different notes, chords, basslines, and melodies to be played. The right hand plucks the strings with its fingertips. A major difference between the theorbo and the Renaissance lute is the position of the right thumb. On the theorbo, the thumb is placed outside the hand, while on the Renaissance lute, the thumb is under the hand. On the theorbo, the right thumb is mainly used to play the bass strings and rarely moves to the higher strings. Most players use the flesh of their fingers on the right hand to pluck the strings. However, some historical sources, such as Piccinini, Mace, and Weiss, mention using fingernails. Fingernails may work better on the theorbo than on the lute because the theorbo has single strings. Using fingernails is often recommended in group music playing, where louder sound is more important than the quality of the tone.

Solo repertoire

The theorbo's solo music from the Baroque period mostly came from Italy and France, except for some English pieces written for the English theorbo, until the 21st century. The best music for the theorbo uses two special features: the diapasons and the reentrant tuning. Campanella passages, which let scales sound across many strings in a way similar to a harp, are often used and are very useful for skilled players.

Italy: Kapsberger, Piccinini, Castaldi
– Toccatas: These are free, expressive pieces with complex harmonies. Piccinini's toccatas have more structured harmonies, while Kapsberger often breaks traditional harmony rules to create unique effects.
– Dances: These include Correntes and Gagliardas, continuing a tradition of Italian lute dances that began with Dalza.
– Variations: These are highly complex and challenging, often based on simple themes.

France: de Visee, Bartolotti, Hurel, le Moyne
– Dance suites: Most French theorbo music includes dance suites with the order: unmeasured prelude, allemande, courante, saraband, and gigue (often with variations).
– Transcriptions: French theorbists often adapted pieces from opera composers like Lully or keyboard composers like Couperin to perform as solo pieces.

A few modern composers have created new music for the theorbo. Important works include those by Roman Turovsky, David Loeb, Bruno Helstroffer, Thomas Bocklenberg, and Stephen Goss, who composed the only concerto for the theorbo.

Continuo

The theorbo was mainly used as a continuo instrument. However, because of its design as a plucked instrument and its reentrant tuning, following strict rules for how notes should follow each other was sometimes difficult or impossible. Because of this, a special style of continuo playing was developed for the theorbo that took these challenges into account:

• Breaking the usual rules for note order to create voicings that highlight the instrument's natural sound. The bass line remains clear by using creative arpeggiation to hide incorrect chord inversions.
• Often moving the bass line down an octave to play on the lower octave strings.
• Using simpler textures. Because the theorbo has strong sound projection and rich resonance, a three- or even two-voice accompaniment can be just as effective as the usual four-voice accompaniment on a harpsichord. Also, playing more than two voices becomes difficult with fast-moving bass lines.
• Striking chords repeatedly to compensate for the instrument's quick sound decay.

Therefore, keeping the bass line and the instrument's sound clear is most important when used as a continuo instrument. Breaking the usual note rules becomes necessary to keep the bass line clear and highlight the theorbo's unique tones.

Praetorius labeled the theorbo as both a basic and decorative continuo instrument, meaning it can support an ensemble as the main bass instrument while also adding harmony and color through chord realizations.

Composers

• Giovanni Girolamo Kapsperger (around 1580–17 January 1651)
• Alessandro Piccinini (30 December 1566–around 1638)
• Angelo Michele Bartolotti (died before 1682)
• Bellerofonte Castaldi (1580–27 September 1649)
• Robert de Visée (around 1655–1732/1733)
• Charles Hurel (died 1692)
• Scott Fields (born 1955)
• Stephen Goss (born 2 February 1964)
• Roman Turovsky (born 1961)

Contemporary players

Xavier Diaz-Latorre was born in 1968.
Eduardo Egüez was born in 1959.
Yasunori Imamura was born on October 19, 1953.
Jakob Lindberg was born on October 16, 1952.
Rolf Lislevand was born on December 30, 1961.
Robert MacKillop was born in 1959.
Massimo Marchese was born on August 31, 1965.
Andreas Martin was born in 1963.
Nigel North was born on June 5, 1954.
Paul O'Dette was born on February 2, 1954.
Christina Pluhar was born in 1965.
Lynda Sayce
Richard Stone was born in 1960.
Stephen Stubbs was born in 1951.
Matthew Wadsworth was born in 1974.
Maria Evangelina Mascardi was born in 1977.
Brandon Acker was born in 1990.