Recordings are not classified according to Library of Congress but rather by a number based on the publishers number (prior to 2008) or on an accession number. General collection levels will be maintained at 3 for standard classical and jazz repertoire, and at a 2 level for ethnomusicology, film music and similar genres. Current popular music will be collected only if requested. Films (DVDs) will be collected for major works, for conductors, performers but not as ephemera.
| Call no. range | Subject | Level | Comments | |
|---|---|---|---|---|
| M1 | Collections of miscellaneous works, 2 or more composers | 3a | ||
| M2 | Collected works of historical, genre, geographic origin.etc. | 3b | Vital for research. | |
| M3-3.1 | Collected works of individual composers. | 3b | Vital for research. | |
| M5 | Miscellaneous collections, 2 or more composers, for varying combinations of instruments. | 2 | Prefer to buy individually when possible. | |
| M6-19 | Organ music | 3 | Organ program no longer exists but existing collection, with occasional additions, is used by area musicians | |
| M20-39 | Piano music | 3b | One of largest COM majors; heavily used | |
| M40-175 | Music for individual solo instruments | 3b | Collect solo music for all instruments | |
| M176 | Motion picture,radio,TV music | 0 | Occasional purchase; often under other instruments or ensembles | |
| M177-179 | Collections for 2 or more miscellaneous solo instruments | 3a | See also M200-900 | |
| M180-195 | Duets for two organs,harmonium | 1 | ||
| M198-216 | Multiple players and/or pianos | 3 | ||
| M217-285 | Piano and one other instrument | 3b | All chamber music with score and parts as available (M200-M999) | |
| M286-298 | Duets without piano | 3b | ||
| M300-986 | Chamber ensembles; trios to nonets | 3 | Trios, quartets, quintets at 3B; larger ensembles 3A | |
| M990 | Chamber music, early instruments | 2 | ||
| M1000-1075 | Orchestra music, all forms, including concertos for solo instrument with orchestra | 3b | For concertos, purchase full score and piano reductions if available (ex. M1010 full score piano concerto; M1011 piano solo and piano reduction | |
| M1100-1160 | String orchestra music | 3a | ||
| M1200-1270 | Band music | 3a | ||
| M1350-1366 | Reduced orchestra, dance orchestra, jazz | 2 | ||
| M1375-1420 | Instrumental music for children | 1 | ||
| M1450 | Dance music | 1 | ||
| M1480-1480 | Electronic, aleatory,chance | 2 | ||
| M1490 | Music printed before 1700 | 1 | Cannot afford originals | |
| M1495-1497 | Collections of vocal music, sacred and secular, 2 or more composers | 2 | Prefer separate editions | |
| M1500-1526 | Operas, musicals, incidental music, ballets | 3b | ||
| M1528-1529 | Duets, trios, etc. for solo voices | 3a | ||
| M1530-1546 | Choruses with orchestra or other ensemble | 3b | ||
| M1547-1610 | Choruses with keyboard, other solo instrument or unison | 3a | ||
| M1611-1626 | Songs, solo cantatas | 3a | ||
| M1627 | National music, international | 2 | ||
| M1628-1677 | National music, US | 2 | Includes popular music (M1630.18) at 3a | |
| M1678-1853 | National music, other regions, continents | 2 | ||
| M1900-1998 | Songs of special character, children's songs, games | 1 | ||
| M1999 | Sacred vocal music, 2 or more composers, various forms | 3a | ||
| M2000-2007 | Oratorios | 3b | Full and vocal scores when possible | |
| M2010-2017 | Services (Roman Catholic, Orthodox, Lutheran, Anglican, etc.) including Masses, Requiems, Vespers, etc. | 3b | Full and vocal scores | |
| M2028-2019 | Sacred duets, trios, etc., solo voices | 3a | ||
| M2020-2036 | Sacred chorus, accompanied (Cantatas, choruses, etc.) | 3b | ||
| M2060-2101 | Sacred choruses, partsongs, keyboard, unison or unacc. (Choruses, anthems, motets, special texts, etc.) | 3a | ||
| M2002-2114 | Sacred songs, solo cantatas | 3a | ||
| M2115j-2146 | Hymnals (combining words and music) | 2 | ||
| M2147-2160 | Liturgy & ritual (prescribed service music for RC, Orthodox, etc.) | 2 | ||
| M2161-2184 | Liturgy & ritual (Protestant) | 2 | ||
| M2186-2184 | Liturgy & ritual, Jewish, other non-Christian | |||
| M2190-2196 | Sacred vocal music for children | 1 | ||
| M2198-2199 | Gospel, revival, temperance | 1 | Special Collections has strong holdings | |
| M5000 | Unidentified compositions | 0 | ||
| MT170-810 | Orchestral studies, exercises, technical materials for all instruments | 3a | 3b for standard orchestral instruments; 3a for harp, guitar, etc. | |
| MT820-893 | Vocal techniques | 3b | ||
| MT898-948 | Techniques for children | 2 | ||