
The Langloz Manuscript: Fugal Improvisation through Figured Bass, edited and analyzed by William Renwick, is a landmark publication in historical music theory. It presents a collection of 18th-century keyboard exercises that bridge the gap between thoroughbass and fugue. This edition provides the necessary tools to understand how the great masters of the Baroque era taught their students to improvise entire polyphonic works from a single, carefully figured bass line.
This book is ideal if you want to:
Explore the advanced pedagogical methods used by Johann Sebastian Bach and his contemporaries.
Transition from basic accompaniment to the art of extemporaneous fugal composition at the keyboard.
Deepen your understanding of the relationship between linear counterpoint and vertical harmony.
Master the specific rules of voice-leading required for authentic historical performance and composition.
You will learn the systematic process of expanding a figured bass into a full four-voice fugue. The book teaches you how to identify fugal subjects hidden within the bass and how to apply the correct countersubjects. By studying these historical examples, you will develop a "polyphonic ear" that allows you to manage multiple independent voices simultaneously while maintaining harmonic clarity and stylistic integrity.
You will learn the systematic process of expanding a figured bass into a full four-voice fugue. The book teaches you how to identify fugal subjects hidden within the bass and how to apply the correct countersubjects. By studying these historical examples, you will develop a "polyphonic ear" that allows you to manage multiple independent voices simultaneously while maintaining harmonic clarity and stylistic integrity.
The historical context of the manuscript and its direct connection to the pedagogy of J.S. Bach.
Detailed instructions for the preparation and execution of fugal answers and tonal mutations.
A complete collection of 37 preludes and fugues designed for practical keyboard realization and study.
Structural analysis of how figured bass symbols dictate complex imitation and contrapuntal textures.
The evolution of the German keyboard tradition from the time of Pachelbel to the late Baroque.
Comparative studies showing the link between these exercises and Bach's Well-Tempered Clavier.
While the original exercises were compiled in the 1700s, this edition is brought to life by William Renwick. He is a Professor of Music Theory and a renowned expert in Schenkerian analysis. Renwick’s scholarly work has been instrumental in reviving interest in the historical methods of composition, making him the perfect authority to curate and explain this complex manuscript.
For the serious student of historical composition, this book is a goldmine of practical information. It provides a "missing link" between the Italian partimento tradition and the rigorous counterpoint of the North. It is absolutely worth it because it transforms abstract theory into a tactile, hands-on experience that will permanently improve your ability to visualize and hear musical structures.
You can check the book and its current availability here:
It is both a scholarly study and a practical workbook containing the original musical exercises for you to realize.
You should have a solid foundation in figured bass and intermediate keyboard skills to get the most out of it.
No, he is the editor and researcher who provides the historical commentary and ensures the accuracy of the musical text.
If you desire to stop looking at early music from the outside and wish to step inside the musical mind of the 15th and 16th centuries, there are three distinct ways we can work together to elevate your skills:
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