Conclusion

The main ideas of the book are briefly summarized. This concluding chapter also presents a refined and expanded canon of part-writing advice for advanced music students. The chapter closes by offering concrete tips for performers and conductors that arise from the science of voice leading.

The Feeling of Leading

A distinction is made between part-writing and voice leading. Even though music may exhibit correct part-writing, the music may nevertheless sounds like it is meandering aimlessly: voice leading adds the sense of tending, yearning, resolution, or momentum that contributes to the feeling of music “going somewhere.” Research on melodic expectation is summarized. When the music fails to conform to expected voice movements, the music is likely to evoke a wandering or purposeless quality. Predictability transforms good part-writing into good voice leading. Predictability is increased when musical patterns follow the norms and clichés of established styles. Familiarity with a given musical work also increases predictability. For unfamiliar works, predictability is increased when music makes use of recurring or imitative figures, themes, or motives.

Sources and Images

An introduction to the perception of sound is given, with special emphasis on topics useful for understanding the organization of music. The chapter covers essential concepts in acoustics and auditory perception, including basic auditory anatomy and physiology. Core concepts are defined such as vibrational mode, pure tone, complex tone, partial, harmonic, cochlea, basilar membrane, resolved partial, auditory image, auditory stream, acoustic scene, auditory scene, and auditory scene analysis.

The Canon

A brief review is provided of sixteen core traditional rules of voice leading as formulated in the late Baroque period. These rules are typically taught as part of the core theory curriculum in conservatories and schools of music.

Hierarchical Streams

Hierarchical streaming is discussed. Auditory scenes can exhibit different levels of organization. At the lowest level, individual partials may amalgamate to form auditory images corresponding to distinct sound sources. At a higher level, these auditory images can combine together to form intermediate musical layers, dubbed textural streams. At the highest level, all of the sound sources may combine to form a unitary percept of the whole experience, dubbed a musical stream. The distinction between auditory streams and textural streams means that there is more to part-writing than simply writing parts; there is also the counterpoint of textural streams. This chapter also introduces scene analysis trees as a graphical analytic tool for better understanding different kinds of musical textures.

Direct Intervals Revisited

The Direct or Hidden Intervals rule has a special status in the voice-leading canon. It offers two lessons. First, the direct intervals rule provides a logical link between three perceptual principles (harmonic fusion, semblant motion, and pitch proximity). The rule provides the glue that establishes a logical interconnection between the various rules of in the voice-leading canon. Said another way, the direct intervals rule points to the unity of the traditional part-writing rules. Second, perceptual experiments testing this traditional rule will lead us to question whether listeners hear nominally four-part harmony as truly evoking four independent lines. This observation leads us to consider possible hierarchical organization of auditory streams—which is the topic of the next chapter.

Embellishing Tones

Chapter 9 discusses embellishing tones—such as passing tones, suspensions, and appoggiaturas. Embellishments can serve a number of functions, including adding dissonance, creating or heightening expectations, drawing attention to neighboring structural tones, or simply adding interest to a musical texture. However, this chapter focuses on how the presence of embellishing tones can contribute to the perceptual independence of concurrent voices. It is shown that embellishing tones are deployed in ways consistent with five different techniques for enhancing voice independence.

Preference Rules

The six auditory principles described in chapters 4, 5 and 6 are used to provide the basis for a detailed explanation of the core rules of voice leading. In presenting this explanatory account, several novel preference rules arise that are not found in past writings on voice leading. These novel rules amount to theory-generated predictions. If the perceptual theory is correct and if past composers regarded the goal of perceptually independent musical lines as worthwhile, then we might expect composers to write in a manner consistent with these novel rules. Indeed, that’s what we find: music written by past composers proves to be consistent with the new preference rules predicted by the perceptual theory.

Introduction

A brief introduction to voice leading practice is provided, including a thumbnail history and two definitions of voice leading. The chapter discusses the role of rules in the art of composition and considers three questions that can help evaluate the utility of any rule. The chapter ends with a description of the plan of the book, Voice Leading: The Science behind a Musical Art, including brief descriptions of the content of each chapter.

The Cultural Connection

The disposition to parse auditory scenes is probably an evolved innate behavior. However, the means by which this is achieved likely involves a mix of innate and learned mechanisms. This chapter reviews research showing how the sonic environment plays a formative role in various aspects of auditory processing. What we commonly hear shapes how we hear sounds. For example, research shows that how musicians hear pitch is affected by what instrument they play. Even the language you speak has an impact on how you hear. It is wrong to assume that everyone parses an acoustic scene in the same way. In general, the research suggests that cultural background and individual experience may be directly relevant to our understanding of auditory scene analysis, and hence to voice leading.