As you know, musicology is divided into theoretical and historical. In Germany, theoretical musicology is called "systematic" and is also opposed to historical. This division, apparently, is a kind of reflection of the long-accepted division of all sciences into "exact" and "humanitarian", with explicitly or implicitly implied preference for "exact" sciences, using in one way or another the mathematical apparatus.
The attribution of music to the mathematical sciences, which took place in the Middle Ages (quadrivium: music, arithmetic, geometry, astronomy, as opposed to the trivium: grammar, dialectics and rhetoric), had absolutely objective grounds in the mathematically accurate development and calculation of musical matter - scale, intervals, frets, rhythms etc. And even in modern times, when the mathematical status of music is a thing of the past, many musical "technological" theories (for example, the theory of movable counterpoint by S.I.Taneev, O. Messiaen's theory and others) possessed the systematicity, accuracy, self-sufficiency and completeness that are inherent in the constructions of mathematics.
Abstract