64. Leopold Mozart notes that the apparent equivalence of, for example, G-sharp and A-flat, D-flat and C-sharp, F-sharp and G-flat is merely a convenience of “Temperatur” (of equal temperament), but that according to “dem richtigen Verhältnisse” (correct [acoustical] relationships), “all notes lowered by a♭ are roughly a comma higher than those raised by a#. D-flat is higher than C-sharp, for example.... Here the good ear must be the judge.” See his Versuch einer gründlichen Violinschule (Augsburg: Johann Jacob Lotter, 1756), 66–67. The passage is translated somewhat differently in Leopold Mozart, A Treatise on the Fundamental Principles of Violin Playing, tr. Editha Knocker (London, New York, Toronto: Oxford University Press, 1951), 70. In practice, the function of the sharped note as leading tone, the flattened note as seventh or ninth, will induce quite the opposite effect, and perhaps it is an inherent tension between the calculus of tempered intervals and the musically functional that magnifies the expressive elocution of such enharmonic relationships.