Interpretations of historical scope of "early music" vary. The original Academy of Ancient Music formed in 1726 defined "Ancient" music as works written by composers who lived before the end of the 16th century. Johannes Brahms and his contemporaries would have understood Early music to range from the High Renaissance and Baroque, while some scholars consider that Early music should include the music of ancient Greece or Rome before 500 AD (a period that is generally covered by the term Ancient music). Music critic Michael Kennedy excludes Baroque, defining Early music as "musical compositions from [the] earliest times up to and including music of [the] Renaissance period".
Musicologist Thomas Forrest Kelly considers that the essence of Early music is the revival of "forgotten" musical repertoire and that the term is intertwined with the rediscovery of old performance practice. According to the UK's National Centre for Early Music, the term "early music" refers to both a repertory (European music written between 1250 and 1750 embracing Medieval, Renaissance and the Baroque) – and a historically informed approach to the performance of that music.
Today, the understanding of "Early music" has come to include "any music for which a historically appropriate style of performance must be reconstructed on the basis of surviving scores, treatises, instruments and other contemporary evidence."
The revival of interest in Early music has given rise to a scholarly approach to the performance of music. Through academic musicological research of music treatises, urtext editions of musical scores and other historical evidence, performers attempt to be faithful to the performance style of the musical era in which a work was originally conceived. Additionally, there has been a rise in the use of original or reproduction period instruments as part of the performance of Early music, such as the revival of the harpsichord or the viol.
The practice of "historically informed performance" is nevertheless dependent on stylistic inference. According to Margaret Bent, Renaissance notation is not as prescriptive as modern scoring, and there is much that was left to the performer's interpretation: "Renaissance notation is under-prescriptive by our standards; when translated into modern form it acquires a prescriptive weight that overspecifies and distorts its original openness. Accidentals ... may or may not have been notated, but what modern notation requires would then have been perfectly apparent without notation to a singer versed in counterpoint".
^Lawson, Colin; Stowell, Robin (1999). The historical performance of music : an introduction (5th printing. ed.). Cambridge: Cambridge University Press. p. 17-18. ISBN9780521627382.
^Margaret Bent, "The Grammar of Early Music: Preconditions for Analysis", p. 25. In Tonal Structures in Early Music, edited by Cristle Collins Judd, 15-59 (Garland Reference Library of the Humanities 1998; Criticism and Analysis of Early Music 1), New York: Garland Publishing, 1998. ISBN0-8153-2388-3.
Davidson, Audrey Ekdahl. 2008. Aspects of Early Music and Performance. New York: AMS Press. ISBN978-0-404-64601-1.
Donington, Robert. 1989. The Interpretation of Early Music, new revised edition. London and Boston: Faber and Faber. ISBN0-571-15040-3.
Epp, Maureen, and Brian E. Power (eds.). 2009. The Sounds and Sights of Performance in Early Music: Essays in Honour of Timothy J. Mcgee. Farnham, Surrey (UK); Burlington, VT: Ashgate. ISBN978-0-7546-5483-4.
Haskell, Harry. 1988. The Early Music Revival: A History. London and New York: Thames and Hudson. ISBN0-500-01449-3.
Haynes, Bruce. 2007. The End of Early Music: A Period Performer's History of Music for the Twenty-First Century. Oxford and New York: Oxford University Press. ISBN978-0-19-518987-2.
Judd, Cristle Collins. 1998. "Introduction: Analyzing Early Music". In Tonal Structures in Early Music, edited by Cristle Collins Judd, 3-13. Garland Reference Library of the Humanities 1998; Criticism and Analysis of Early Music 1. New York: Garland Publishing. ISBN0-8153-2388-3.
Roche, Jerome, and Elizabeth Roche. 1981. A Dictionary of Early Music: From the Troubadours to Monteverdi. London: Faber Music in association with Faber & Faber; New York: Oxford University Press. ISBN0-571-10035-X (UK, cloth); ISBN0-571-10036-8 (UK, pbk); ISBN0-19-520255-4 (US, cloth).
Sherman, Bernard. 1997. Inside Early Music: Conversations with Performers. New York: Oxford University Press. ISBN0-19-509708-4.
Stevens, Denis. 1997. Early Music, revised edition. Yehudi Menuhin Music Guides. London: Kahn & Averill. ISBN1-871082-62-5. First published as Musicology (London: Macdonald & Co. Ltd, 1980).