Aaron[Aron], Pietro[Piero](bFlorence,c1480;dafter 1545).Italiantheoristandcomposer. Nothing is known of Aaron's early training, his teacher, or his career before 1516. He claims to have had the greatest friendship and familiarity with Josquin, Obrecht, Isaac and Agricola in Florence (most likely between 1487 and 1495, and not necessarily at the same time). By 1516 he was a priest in Imola, where he wrote his first book,Libri tres de institutione harmonica, translated into Latin by the humanist Giovanni Antonio Flaminio. A contemporary poem by Achille Bocchi praises Aaron for rescuing music from squalor and dismal neglect. By March 1520 he was a singer in Imola Cathedral; he was also paid by the city to teach music to those who wished to learn. He resigned in June 1522, and by February 1523 he was in Venice in the household of Sebastiano Michiel, Grand Prior of the Knights of St John of Jerusalem, to whom he dedicated hisToscanello. When his patron died in 1536, Aaron became a Crutched Friar in a monastery near Bergamo. He lived to see hisLucidariopublished in 1545, but perhaps not his undatedCompendiolo, in which theLucidariois mentioned.Apart from his brief stay at Imola, Aaron held no formal position as singer or choirmaster, an unusual situation that might be due to his Jewish origin (a hypothesis explored in Blackburn, Lowinsky and Miller). Born in tenuous circumstances (Toscanello, preface), he seems to have been largely self-taught; this may be the reason for his less systematic approach and questionable statements (especially in his first treatise), but also for his valuable insights into contemporary practice: from his first treatise onwards he promises to divulge many of the secret chambers of this art, never heretofore revealed. He is especially informative on counterpoint and compositional process (distinguishing older and newer procedures), the modal system in polyphonic music and the application ofmusica ficta. He is one of the first theorists to discuss mean-tone temperament. HisToscanello, among the earliest vernacular music treatises, was highly successful and ran to four editions.Aaron spans the generation between Franchinus Gaffurius and Gioseffo Zarlino. His roots lie in the teachings of John Hothby, Johannes Tinctoris, and above all in Gaffurius'sPractica musice. Despite the humanistic trappings of his first treatise (perhaps owing to his translator), his orientation is largely practical. No theoretical innovator, he sought to apply the standard teachings on mode, counterpoint andmusica fictato contemporary music when doing so was becoming ever harder. His observations on the problems involved are particularly illuminating.Aaron owes much to his friend and fellow theoristGiovanni Spataro. Mostly by letter (only Spataro's survive), they discussed notation, composition and arcane uses of accidentals. Their early exchanges on notation, prompted by the errors in theLibri tres, led to an improved treatment in theToscanello, which Spataro reviewed in nine letters (six survive). Aaron took Spataro's comments into account (without acknowledgement) in the 1529 edition. Spataro also wrote a lengthy critique of theTrattato(now lost), which he called without order and truth; in theLucidarioAaron quoted Spataro frequently, this time by name.In his most original treatise, theTrattatoof 1525, Aaron tried to apply Marchetto of Padua's modal theory to the existing polyphonic repertory, citing numerous compositions in Petrucci's publications. For him, as for Tinctoris, the mode was borne by the tenor and determined by final, range and species of 5ths and 4ths. He explained endings ona,bandc' not due to transposition (which did not fit Marchetto's system) by confinals and psalm tone differences, with preference given to the latter seemingly a measure of desperation, for want of the new modes later proposed by Glareanus. He then showed how every syllable of the hexachord could be found on each note of the Guidonian hand. Severely criticized by Spataro for using only the flatconiuncta(e.g.uton D is D, not D), in 1531 he published a revised treatment an untitled pamphlet bound with some copies of theTrattatoand theToscanello in which all the syllables are derived frommiorfa. The theory had been covered by Hothby, but Aaron's explanations are much clearer. In theLucidarioAaron considered the possibility of F, C, Band E(a subject discussed with Spataro), but as a confirmed Pythagorean did not equate them with E, B, C and F. The manuscriptDelli principiicompares Aaron's, Stefanus Vanneus's and Gaffurius's initial notes for each mode (given its Greek name).Despite similar content, theToscanellois not a translation of theLibri tres: some sections are omitted (on chant, solmization, mutation), some duplicated (fundamentals), some improved (notation), some expanded (notably on counterpoint and composition) and some added (division of the monochord, tuning of keyboard instruments). The aggiunta of 1529 counsels composers to sign accidentals, citing with approval numerous examples of flats written to mitigate melodic tritones (normally less tolerable than diminished 5ths) or avoid diminished perfect intervals: accidentals are like sign-posts, necessary even for the learned.TheLucidariois an interesting and unusual treatise on a wide range of theoretical disputes: plainchant, notation and counterpoint, and further thoughts on topics from his earlier treatises, with replies to some of Gaffurius's criticisms of theLibri tres. Book 4 incorporates the 1531 pamphlet, a few more questions of notation and accidentals, a disquisition on the Greek mode-names and the famous list of singers a libro and al liuto. TheCompendiolo, an elementary manual largely derived from his first two treatises, is of less interest.Aaron's influence extended throughout the 16th century, most notably in his pupil Illuminato Aiguino's treatises on modes in plainchant (1562) and polyphony (1581).WORKSIo non posso pi durare, 4vv, 15056

Lost works (mentioned in letters): Credo, 6vv; In illo tempore loquente Jesu; Letatus sum; Mass, 5vv; motet on c.f. Da pacem; other motets and madrigals

WRITINGSLibri tres de institutione harmonica(Bologna,1516/R)Thoscanello de la musica(Venice,1523/R, 2/1529/R) with suppl. asToscanello in musica nuovamente stampato con l'aggiunta, 3/1539/R, 4/1562 [the 1557 edn is a ghost]; Eng. trans. collating all edns by P. Bergquist (Colorado Springs, CO, 1970)Trattato della natura et cognitione di tutti gli tuoni di canto figurato(Venice,1525/R); Eng. trans. of chaps. 17 inStrunkSRuntitled treatise on mutations (Venice,1531) [attached to some copies ofToscanelloandTrattato]Lucidario in musica di alcuni oppenioni antiche et moderne con le loro oppositioni et resolutioni(Venice,1545/R)Compendiolo di molti dubbi, segreti et sentenze intorno al canto fermo, et figurato(Milan, after1545/R)Delli principii di tuti li tono secondo mi Pietro Aron(MS, after1531,GB-Lbl) [not autograph], bound with Bonaventura da Brescia:Regula musice plane(K.1.g.10)9 letters inI-RvatVat.Lat.5318,F-PnItal.1110,D-BsbMus.ms.autogr.theor.1; ed. inSpataroCBIBLIOGRAPHYGrove6(Mode, III, 3; H.S. Powers)SpataroCP.Bergquist:The Theoretical Writings of Pietro Aaron(diss., Columbia U.,1964)P.Bergquist:Mode and Polyphony around 1500: Theory and Practice,Music Forum, i (1967), 99161C.Dahlhaus:Untersuchungen ber die Entstehung der harmonischen Tonalitt(Kassel,1968; Eng. trans., 1990)B.Meier:Die Tonarten der klassischen Vokalpolyphonie(Utrecht,1974; Eng. trans., 1988)M.Lindley:Early 16th-Century Keyboard Temperaments,MD, xxviii (1974), 12951E.Apfel:Diskant und Kontrapunkt in der Musiktheorie des 12. bis 15. Jahrhunderts(Wilhelmshaven,1982)K.Berger:Musica ficta: Theories of Accidental Inflections in Vocal Polyphony from Marchetto da Padova to Gioseffo Zarlino(Cambridge,1987)B.J.Blackburn:On Compositional Process in the Fifteenth Century,JAMS, xl (1987), 21084H.Powers:Is Mode Real? Pietro Aron, the Octenary System and Polyphony,Basler Jb fr historische Musikpraxis, xvi (1992), 952C.C.Judd:Modal Types andUt,Re,MiTonalities: Tonal Coherence in Sacred Vocal Polyphony from about 1500,JAMS, xlv (1992), 42867A.M.Busse Berger:Mensuration and Proportion Signs: Origins and Evolution(Oxford,1993)M.Bent:Accidentals, Counterpoint, and Notation in Aaron'sAggiuntato theToscanello,JM, xii (1994), 30644C.C.Judd:Reading Aron Reading Petrucci: the Music Examples of theTrattato della natura et cognitione di tutti gli tuoni(1525),EMH, xiv (1995), 12152BONNIE J. BLACKBURN