Library of Congress Classification: Class M: M1-M5000

Sources: Class M; Mark McKnight. Music classification systems, 2002.

Class numbers in the Library of Congress Classification system are alpha-numeric. The letter portion includes one or more capital letters to indicate the general subject area. The number portion includes one or more Arabic numbers to subdivide the subject area.

Class M, for music, is subdivided into three main sections:
M notated music - musical works, either as scores or some other form of notation
ML literature of music - books about music, such as biographies, histories, discographies, thematic indexes, musical ethnographies, etc.
MT musical instruction and study - method books, studies and exercises intended for pedagogical use (as opposed for concert use), treatises, books on music theory, music-appreciation textbooks (even those with extensive musical examples), etc.; includes both scores and books.

General guidelines for Class M

Source: http://www.loc.gov/catdir/cpso/LCC_M_GL.pdf

Definitions of collection:

1. an item containing compositions by two or more composers;

2. an item containing works by one composer and selected from two or more of the composer's works;
   or,

3. an item containing one composer's works in more different forms or for a greater variety of performers than are provided for by any more specific class.

A collection is not to be confused with a set, which is a group of compositions published as a single work. This can be determined by an identifying number, such as an opus number or book number, etc., or a qualifying number that indicates the individuals parts are part of a larger work.

Further subclasses of collections are:
Miscellaneous collection: contains both original and arranged works
General collection: contains a greater variety of forms or types of works than may be provided for by any more specific neighboring class.
Special collection: contains two or more works by one or more composers that are of the type indicated for separate works, e.g., class collections of string quartets as well as individual string quartets in M452-M452.4. 

Class numbers for instrumental music

Class numbers for instrumental music focus on number of instruments and are easy to remember. Music for two instruments is generally classed in M2XX; three instruments in M3XX, etc., until M9XX, where music for nine instruments is classed as well as for chamber music for ten or more instruments, one to a part.

Many class numbers are subarranged according to whether it is a collection (a miscellaneous collection of original and arranged works; a collection of original works; or a collection of arranged works) or a separate work that is original or a separate work that is arranged. When this subarrangement is used, a span of 5 class numbers are given, to be subarranged according to Table 2, Table of original works and arrangements.

Each number in the first row is the last digit in the first number of a span of numbers (i.e., M60-M64, M224-M228).

The table has been expanded to include the first digit 0.

For example, the span of numbers for viola and piano music is M224-M228. Take the last letter (4) of the first number in the range (224) and go to Table 2. Find "4" in the top row and following the numbers down from there:

M224 for a collection (2 or more works) of original and arranged works for viola and piano
M225 for a collection (2 or more works) of original works for viola and piano by one or more composers
M226 for a single original work for viola and piano by one composer
M227 for a collection (2 or more works) of arranged works for viola and piano by one or more composers
M228 for a single arranged work for viola and piano by one composer (including excerpts from a single work by one composer)

The span of numbers for five wind instruments is M555-M559, which is also subarranged using Table 2.

M555 for a collection (2 or more works) of original and arranged works for five wind instruments (woodwind and/or brass)
M556 for a collection (2 or more works) of original works for five wind instruments (woodwind and/or brass)
M557 for a single original work for 5 woodwind and brass instruments
   M557.2 for a single original work for viola and piano by one composer for 5 woodwind instruments
   M557.4 for a single original work for viola and piano by one composer for 5 brass instruments
M558 for a collection (2 or more works) of arranged works for five wind instruments (woodwind and/or brass)
M559 for a single arranged work for five wind instruments (woodwind and/or brass) (including excerpts from a single work by one composer)

The complication is that there are two subfamilies of wind instruments:
woodwinds: flute, oboe, clarinet, recorder, saxophone, bassoon, etc.
and
brasses: horn, cornet, trumpet, trombone, baritone, euphonium, tuba, etc.

Note that the class number M557 is further subdivided: M557 is for quintets for a combination of both woodwind and brass instruments; M557.2 for only woodwind quintets, and M557.4 for only brass quintets. (Adding to the confusion is the terminology "woodwind quintet," which is used for quintets with flute, oboe, clarinet, horn, and bassoon. These qualify as "wind" quintets for cataloging purposes because they include a non-woodwind instrument; the horn is a brass instrument.) The rest of the span of numbers is not similarly subdivided. For example, M556 is used for collections of original works for either wind quintets, woodwind quintets, or brass quintets, not M556, M556.2, and M556.4. M559 is used for a single work arranged for either wind quintet, woodwind quintet, or brass quintet; M559.2 and M559.4 are not used.

Class numbers for orchestra, string orchestra, and band music
The class numbers for orchestra, string orchestra, and band music (not including works for solo instrument(s) and orchestra, string orchestra, or band) vary from those for chamber music. Many individual forms within these ranges are assigned separate numbers. The same class number is applied to both individual works and collections of works.

M1000-M1075 for orchestra
M1100-M1175 for string orchestra
M1200-M1268 for band (the numbers in this range vary some from the individual numbers in M1000-M1075 and M1100-M1175)

M1001 = an individual symphony or a collection of symphonies for orchestra
M1101 = an individual symphony or a collection of symphonies for string orchestra
M1201 = an individual symphony or a collection of symphonies for band

M1002 = an individual symphonic poem or a collection of symphonic poems for orchestra
M1102 = an individual symphonic poem or a collection of symphonic poems for string orchestra
M1202 = an individual symphonic poem or a collection of symphonic poems for band

M1003 = an individual suite, variations or a collection of suites, variations for orchestra
M1103 = an individual suite, variations or a collection of suites, variations for string orchestra
M1203 = an individual suite, variations or a collection of suites, variations for band

M1004 = an individual overture of a collection of overtures for orchestra
M1104 = an individual overture of a collection of overtures for string orchestra
M1204 = an individual overture of a collection of overtures for band

M1042 = an individual concerto or a collection of concertos for orchestra
M1142 = an individual concerto or a collection of concertos for string orchestra
M1242 = an individual concerto or a collection of concertos for band

Works not in one of these forms fall under the catch-all term "pieces," although even these have numbers for individual forms:

M1045 = an individual piece or a collection of pieces for orchestra
M1145 = an individual piece or a collection of pieces for string orchestra
M1245 = an individual piece or a collection of pieces for band

M1046 = an individual march or a collection of marches for orchestra
M1146 = an individual march or a collection of marches for string orchestra
M1247 = an individual march or a collection of marches for band

M1047 = a collection of dances for orchestra
M1147 = a collection of dances for string orchestra
M1247.9 = a collection of dances for band

The class numbers for dances are further subdivided according to two-rhythm (polka, etc.) and three-rhythm (waltz, etc.):

M1048 = an individual two-rhythm dance or a collection of two-rhythm dances for orchestra
M1148 = an individual two-rhythm dance or a collection of two-rhythm dances for string orchestra
M1248 = an individual two-rhythm dance or a collection of two-rhythm dances for band

M1049 = an individual three-rhythm dance or a collection of three-rhythm dances for orchestra
M1149 = an individual three-rhythm dance or a collection of three-rhythm dances for string orchestra
M1249 = an individual three-rhythm dance or a collection of three-rhythm dances for band

Classifying works with keyboard:
Piano, etc.: "Unless specific classes are otherwise available, the term is meant to include harpsichord, clavichord, virginal, and similar keyboard instruments whose strings are plucked or struck."
Continuo: "Class works with continuo parts as if the continuo were played by one, not two, performers, and, in general, as if the chordal portion of the continuo part were for piano (harpsichord, etc.)"

Studies and exercises:
Pedagogical works (with or without accompaniment): class in MT studies and exercises
Concert works: class concert works titled "studies" by medium of performance in class M.
 

Class numbers for vocal music

Class numbers for vocal music tend to emphasis the accompaniment and are less easy to remember.

Secular and sacred works of the same type and for the same medium of performance are classed in different class numbers. For example, a secular song for voice and orchestra is classed in M1613 and a sacred song for voice and orchestra in M2103. There is no pattern like M1613/M2113 or M1619/M2119 in the class schedule, making it difficult to memorize the class numbers.

Limitations of Class M

• The schedule is inconsistent in the level of detail.

  • Many classes are subdivided in detail. For example, the class numbers for music for organ (M6-M14), piano (M20-M39), violin and piano (M217-M223), violoncello and piano (M229-M236), and orchestra (M1000/M1075) are further subdivided by type of composition (suite, sonata, symphony, etc.)

  • Other class numbers are so general that a wide variety of works are classed in it. For example, see the class numbers M298 and M298.5 and M385, M485, M685, etc. and M386, M486, M586, etc. Most works that include percussion are classed in one of these class numbers, because percussion is not covered elsewhere in the schedule.

  • Still other class numbers are in-between highly detailed and not detailed enough. For example, all music for two wind instruments, original or arranged, are classed in just two class numbers: M288 (collections) and M289 (separate works).

• The entire schedule is oriented toward western art music.

• It is difficult to use Class M to classify sound recordings. (Some libraries use a variation of LC Class M; other libraries shelve recordings by accession number or manufacturer number. One system used by many public libraries is the ANSCR classification system for sound recordings, which includes over fifty major categories into which sound recordings may be organized.)

Outline of Library of Congress Classification: Class M