Editing Historically informed performance (section)

===Interpreting musical notation===
Some familiar difficult items are as follows:

*Early composers often wrote using the same symbols as today, yet in a different meaning, often context-dependent. For example, what is written as an [[appoggiatura]] is often meant to be longer or shorter than the notated length,<ref>C. P. E. Bach, ''Versuch über die wahre Art das Clavier zu spielen'', Berlin 1753: Teil 1, Section 2 Par. 5.</ref> and even in scores as late as the 19th century there is disagreement over the meaning (dynamic and/or agogic) of hairpins.<ref>{{Cite book|last=Poli|first=Roberto|title=The Secret Life of Musical Notation|publisher=Amadeus Press|year=2010|location=Milwaukee, WI}}</ref>
*The notation may be partial. E.g., the note durations may be omitted altogether, such as in [[unmeasured prelude]]s, pieces written without [[Beats per minute|rhythm]] or [[Measure (music)|metre]] indications. Even when the notation is comprehensive, non-notated changes are usually required, such as rhythmic shaping of passagework, pauses between sections, or additional arpeggiation of chords. Cuts and repetitions were common.
*The music may be written using alternative, non-modern notations, such as [[tablature]]. Some tablature notations are only partially decoded, such as the notation<ref>Peter Greenhill, ''The Robert ap Huw Manuscript: An Exploration of its Possible Solutions'', 5 vols. (all), Bangor: University of Wales, CAWMS dissertation, 1995–2000.</ref> in the harp manuscript<ref>Thurston Dart, "Robert ap Huw's Manuscript of Welsh Harp Music", ''The Galpin Society Journal'', Vol 21 (1963). {{JSTOR|841428}}.</ref> by [[Robert ap Huw]].
*The reference [[Pitch (music)|pitch]] of earlier music cannot generally be interpreted as designating the same pitch used today.
*Various tuning systems ([[Musical temperament|temperament]]s), are used. Composers always assume the player will choose the temperament, and never indicate it in the score.<ref>"Stimmung und Temperatur", in F. Zaminer, ed., ''Geschichte der Musiktheorie'', Vol. 6: "Hören, Messen und Rechnen in der Frühen Neuzeit", Darmstadt, Germany: Wissenschaftliche Buchgesellschaft (1987) {{ISBN|978-3-534-01206-0}}.</ref>
*In most ensemble music up to the early Baroque, the actual musical instruments to be used are not indicated in the score, and must be partially or totally chosen by the performers. A well-discussed example can be found in Monteverdi's ''[[L'Orfeo]]'', where the indications on which instruments to use are partial and limited to critical sections only.<ref>Jane Glover, "Solving the Musical Problem" in John Whenham (ed.) ''Claudio Monteverdi: Orfeo'', 138–155. Cambridge, England: Cambridge University Press, 1986. {{ISBN|0-521-24148-0}}</ref>
*Issues of pronunciation, that impact on musical accents, carry over to church [[Latin]], the language in which a large amount of early vocal music was written. The reason is that Latin was customarily pronounced using the speech sounds and patterns of the [[Latin regional pronunciation|local]] vernacular language.