In this episode, I talk with Professor Blachly. Professor Blachly is the author of articles on the German dialect of Gregorian chant, the difference between tapping time and conducting time visually in the 15th and 16th centuries, puzzle-pieces of the late Middle Ages, the evolution of musical notation in the 13th through 16th centuries, the performance of the music of Lassus and Palestrina, archaic polyphony of the Renaissance, thoughts on the performance of 12th-century Calixtinus music, and the development of proportions in 14th- and 15th-century music. His research interests cover renaissance music, gregorian chant, numerically-based polyphony, just intonation, medieval puzzle pieces, medieval and renaissance music history, and choral arrangements of nineteenth-century lieder.