thorough bass: see figured bass.

sea bass: see bass.

ground bass, melodic phrase used repeatedly as a bass line. In its earlier form, developed in the 13th and 14th cent., the ground or basso ostinato [Ital.=obstinate] never varied in harmonization or pitch. The tenor, or pes, of Sumer Is Icumen In is such a ground. Another sort was developed during the 17th cent. by Purcell and his contemporaries. This ground was not rigid as to pitch, sometimes moving from bass to soprano. It was composed with varying melodies and harmonies in the upper parts. The result was often a series of variations as in the baroque chaconne and passacaglia. The device often has great dramatic effect. J. S. Bach and Handel made remarkable use of it.

figured bass, in music, a system of shorthand notation in which figures are written below the notes of the bass part to indicate the chords to be played. Called also thorough bass and basso continuo, it arose in the early 17th cent. in Italy as a means of notating an accompaniment. It soon became so widespread that the baroque era is sometimes called the age of basso continuo. The harpsichord's part in sonatas was indicated by a figured bass, and the harpsichord and the organ are usually played from a figured bass in the vocal works of Bach and Handel. The realization of the basso continuo involves considerable improvisation, varying in style according to composer and period. Both Bach and Mozart wrote out rules for playing the figured bass. After the time of Bach, with the development of the symphony, the figured bass disappeared except for limited use in opera and as a device for teaching harmony.

double bass, bowed stringed musical instrument, the contrabass of the modern orchestral string section. It originated as a double-bass viol, an instrument described as early as 1566. A true double-bass violin appeared during the 18th cent. but was rejected as unwieldy and of poor tonal quality. The present double bass is tuned in fourths and usually has a flat back and sloping shoulders but has never attained a definitive form. The bow, the last to give up its convex shape, was long held palm upward like the viol bow, but the violin style is now customary. Indispensable in the orchestra, it also has a place in the dance band and jazz.

bass viol, properly, the largest instrument of the viol family. The term now refers most often to the double bass.

bass, common name applied to various fishes of the families Serranidae (sea basses) and Centrarchidae (black basses and sunfishes). The sea basses are a large, diverse, and important family of perchlike fishes with oblong, rather compressed bodies. All basses are carnivorous and most are marine, although several species are found in freshwater (see sunfish). Sea basses inhabit warm and temperate seas throughout the world and are highly valued as game and food fishes. Along the Atlantic coast as far north as Cape Cod is found the common, or black, sea bass, a sluggish bottom fish averaging 6 lb (2.7 kg) in weight and 18 in. (45 cm) in length. Offshoots of the sea basses and classified with them are the white basses, including the striped bass (or rockfish) and the white perch, both found in fresh and brackish waters from Florida to Canada; the white bass of the Mississippi valley and the Great Lakes; and the similar but smaller yellow bass, found in the same range. The white sea bass of the N Pacific, however, is a member of the Sciaenidae family (see croaker). The Pacific sea basses include the giant sea bass, or Pacific jewfish, a bulky bottom fish that reaches a weight of 600 lb (270 kg) and a length of 7 ft (2.1 m), as well as the 2-ft (60-cm) kelp and sand basses. The so-called Chilean sea bass, or Patagonian toothfish (Dissostichus eleginoides), of the deep, cold waters of the Southern Hemisphere, is a member of the Nototheniidae family. The groupers are an important genus of large tropical sea basses. Very closely allied to the sea basses are the tripletail, with prominent anal and dorsal fins, and the robalo, or snook, widely distributed in tropical American saltwaters. Basses are classified in the phylum Chordata, subphylum Vertebrata, class Osteichthyes, order Perciformes, families Serranidae and Centrarchidae.

bass, in musical harmony, the part of lowest pitch. The term is used for the lowest-pitched male voice and for instruments of low pitch, such as bass clarinet, bass drum, bassoon (bass oboe), and bass trombone.

Otis, Bass, 1784-1861, American portrait painter and mezzotint engraver, b. Bridgewater, Mass. He probably produced the first lithograph in America, a portrait of the Rev. Abner Kneeland, in a volume of his lectures (1818). Otis practiced portrait painting in New York City and Philadelphia, reproducing some of his works in mezzotint. Among his best-known likenesses are those of Thomas Jefferson, Stephen Girard, and James Madison. His only known genre composition, Interior of a Smithy, is in the Pennsylvania Academy of the Fine Arts.

Bass Strait, channel, 80 to 150 mi (129-241 km) wide, between Tasmania and Victoria, SE Australia, connecting the Indian Ocean and Tasman Sea; Port Phillip Bay and Melbourne are on the northwest coast. Bass Strait is an important fishing area. The exploration of the strait by Englishman George Bass in 1798 proved that Tasmania was not a part of the Australian continent.

Lowest-pitched of the modern stringed instruments. It varies in size, up to 80 inches (200 cm) tall. Its shape also varies; its shoulders usually slope more than those of the violin, reflecting its status as a hybrid of the viol and violin families (the name comes from the double-bass viol). It emerged from these families in the late Renaissance, and it has always been less standardized in form than its cousins in the violin family. It normally has four strings; the orchestral instrument often has a lower fifth string (more often, an extension is added to the fourth string), and the jazz instrument has a higher fifth string. Its range is an octave below that of the cello. It is normally bowed in orchestral music and plucked in jazz. In rock bands and some jazz bands, the electric bass is used instead.

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Any of about 400 species (family Serranidae) of carnivorous fishes, most of which inhabit shallow regions of warm and tropical seas. Sea bass have a slender body, small scales, large mouth, and straight-edged or rounded tail. The spiny frontal section and the soft-rayed rear section of the dorsal fin are usually joined but may be separated by a notch. Species range from about 1 in. (3 cm) to 6 ft (1.8 m) long and may weigh 500 lbs (225 kg). About 12 species in the family Moronidae (sometimes considered a subfamily of Serranidae) inhabit temperate waters. Seealso bass.

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or basso continuo

In Baroque music, a special subgroup of an instrumental ensemble. It consists of two instruments reading the same part: a bass instrument, such as a cello or bassoon, and a chordal instrument, most often a harpsichord but sometimes an organ or lute. Its appearance in the early 17th century reflected the radically new musical texture of accompanied melody that was especially typical of the new vocal genre of opera. The continuo (which has a counterpart in the bass and rhythm guitar of a rock band) came to be employed in virtually all ensemble music of the Baroque era.

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Any of about six species (genus Micropterus) of slender freshwater fishes of the sunfish family; found in eastern North America. Two, the largemouth and smallmouth black basses, have been introduced into other countries and are prized as hard-fighting game fishes. Black basses are larger and longer-bodied than sunfishes and more predatory. The largemouth bass may grow to 32 in. (80 cm) long and weigh 22 lbs (10 kg); it lives in quiet weedy lakes and streams. The smallmouth bass, which usually grows to 5–6 lbs (2–3 kg), inhabits clear, cool lakes and running streams.

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Lowest musical voice or register. In vocal music, its range is approximately from the second E below middle C to middle C itself. A basso profundo emphasizes a lower register, a basso cantante a somewhat higher one. Outside of Russia, the solo bass voice has generally been relegated to certain standard operatic character roles. The lowest-pitched member of most instrumental families is usually called the bass (bass clarinet, double bass, etc.). In Western tonal music, the bass part is usually second in importance only to the melody, being the chief determiner of harmonic movement, a tendency that became particularly notable after the appearance of the basso continuo circa 1600.

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Strait separating mainland Australia from Tasmania. It is some 150 mi (240 km) wide at its widest point, about 185 mi (300 km) long, and 180–240 ft (55–75 m) deep. It was named in 1798 for the British surgeon-explorer George Bass. Development of its offshore petroleum resources began in the 1960s.

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