In this week's episode, Nariá Assis and Luís Raimundo investigate sound masses. Their insightful analytical discussion touches on the intricate relationship between texture and rhythm, the historical evolution of the use of sound masses, and current applications in both modern and contemporary classical and electronic music.

This episode was produced by Katrina Roush along with Team Lead Anna Rose Nelson.

SMT-Pod Theme music by Zhangcheng Lu; Closing music "hnna" by David Voss. For supplementary materials on this episode and more information on our authors and composers, check out our website: https://smt-pod.org/episodes/season03/

Welcome to SMT-Pod, the premiere audio publication of the Society for Music Theory. In this week's episode, Nariá Assis and Luís Raimundo investigate sound masses. Their insightful analytical discussion touches on the intricate relationship between texture and rhythm, the historical evolution of the use of sound masses, and current applications in both modern and contemporary classical and electronic music.

Greetings. I'm Nariá Assis.

And I’m Luis Raimundo.

Today we are going to talk about the universe of sound masses, a specific textural genre of modern classical music. Sound masses are musical structures that emphasize texture and timbre rather than melody or metrical rhythm (which we are used to encountering in so many kinds of music).

We are going to discuss how rhythm interacts with texture in various types of sound masses, giving you a brief overview of how these concepts were treated in the past and how they have become a bit obsolete when it comes to dealing with modern and contemporary classical music. We will propose different approaches to rhythm and texture, discuss the concept of density, and illustrate our discussion with several examples not only from classical music but also from contemporary electronic music as well.

Please, join us as we journey through this unusual and fascinating musical domain.

Well, let’s begin by giving a brief overview of the concept of texture. Without wanting to engage in any kind of philological debate about this concept, I would simply say that “texture” relates to the types and degree of connection of internal parts within materials.

Yes, from a lexical perspective, the original sense of the term “texture” came from the Latin word textura, meaning something related to the weaving of a fabric. However, as simple as it might look, this definition becomes rather problematic when applied to the arts, namely to music, since it is based on a material as ephemeral and diaphanous as sound. Back in 1959, Robert Simpson wrote that terms such as texture and I quote, "have been used loosely until they cease to mean much, yet, we still go on repeating them as slogans." Similarly, Jonathan Dansby admits that inherent difficulties of this concept suggesting that it might never reach the same type of understanding as concepts like rhythm, or pitch, for instance.

Even so, it is unquestionable that this term has been widely used for a long time in musicological discourse. Traditional textural labels like monophony or the existence of a single musical line, but also homophony, heterophony, and most of all polyphony, continue to be used nowadays to describe musical textures, even when it comes to music from the modern period.

No doubt. There are several terms used in connection with musical textures. Back in the nineties, Robert Strizich suggested polyphonic textural subtypes, like complex polyphony, disjunct polyphony, or multi-layered polyphony, applied to 20th-century music. Also, several of Ligeti’s compositions reveal a canonic type of writing that the composer himself refers to as micropolyphony. For example, in the initial bars of Lontano, all the instruments share the same chromatic melody, approached in a canonical way. Through the several subtle and rhythmically uncoordinated entrances, the composer achieves a dense, and timbrally rich web of sound. Let’s hear it.

Ex. 1: Ligeti, Lontano [20’’- 1’]

But it looks obvious that, in the former example, one does not hear the fugato type of writing that exists in the score, but instead a compact sound block, which suggests that the term "polyphony" might not be the most appropriate to characterize this kind of music. This suggests an opposite relationship between the poietic level, or, in other words, the canonical technique used by Ligeti, and the esthesic level of reception. And this brings us closer to the topic under discussion, the concept of sound mass. Can we try to define it?

Yes, of course. The expression ‘sound mass’ began to gain momentum in the 1960s, as an attempt to describe specific types of music, particularly the compositions of Xenakis, Penderecki, and Ligeti. Several composers and music theorists have employed related terminologies such as "sound clouds", "webs", "wholes", "aggregates", and so forth. The concept of sound mass is closely related to the post-tone music idea, postulated by Jason Noble and Stephen McAdams, in which discrete sounds are replaced by masses of sounds. It's the type of music that primarily deals with spectromorphologies and auditory shapes instead of individual sounds.

Another related question is that, while the expression ‘sound mass’ has emerged within the specific field of modern classical music, mostly in the textural music domain, nowadays it can be applied to a vast array of musical types and gestures. But anyway, to give a brief definition of sound mass, I think that at its core it's all about those passages and fragments in music where individual notes and lines, musical layers, rhythms, etc. converge, blending their distinct identities into a singular entity. One good example of this is Atmosphères, also by Ligeti.

Ex. 2: Ligeti, Atmosphères, [1’10’’ - 1’30’’]

In the listened excerpt, the timbric homogeneity, the stillness that runs through the great number of individual lines, and the extreme closeness of single sounds, submerge our perception of many distinct lines into one big and compact wall of sound.

Yes, I agree. Another paradigmatic example is a passage from the Threnody to the Victims of Hiroshima by K. Penderecki. In this short fragment, contrasting with the previous one we’ve heard, there's a pronounced timbral heterogeneity, resulting from the diversity of attacks and articulations in the strings. Moreover, the close temporal proximity of events, that is, the highly animated rhythms, cause the multiple lines to coalesce into a singular and dense event characterized by a rich and agitated internal texture.

Ex. 3: Penderecki, Threnodie, [1’45’’ - 2’]

Well, focusing now on the rhythmic perspective, we could say there are three general notions of rhythm we could think about. The first one is specifically musical and comes from the music of the common practice period. In this context, rhythm is approached in terms of patterns of duration, sometimes identified with terms borrowed from Greek prosody like trochaic or iambic, as in Cooper & Meyers’ seminal theory, and other times as a result of the process of grouping sounds, a process that follows the rules of Gestalt theories and linguistics, as in Lerdahl & Jackendorff’s well-known theory.

This notion also assumes rhythms are inscribed in a metrical grid, that is to say, there are beats enunciated at various levels or rates, synchronized with each other. Beats emerge because there are periodic articulations or accents. In sum, in this first notion, periodicity is a fundamental trace of rhythm. [Background music].

The second notion is rhythm in a general sense, not just musical. Rhythm can be described, according to musicologist Curt Sachs, as containing two basic features: movement and moderation. The Greek word rythmos means “particular way of flow”, which expresses very well what this second notion is about. We could apply this notion to describe natural rhythms such as wave motion, bird songs, different states of human breath, etc., as well as to describe rhythm in artistic contexts like contemporary dance or beatless music, for example. Autechre’s song Rettic A, which we are hearing now is an excellent example of this. [Background music].

There are many other beatless types of music throughout Western Classical music history. Among which some examples come to mind. One is the medieval voice genre, the Gregorian chant, in which unmetered rhythm is established by word flow and Latin. But also there were various modern composers who developed extremely complex rhythmic organizations that resulted in music without a regular pulse, like, for example Babbitt, Stockhausen, or Ferneyhough. The third and last notion is, in fact, a non-rhythmic idea. Two cases of complete absence of rhythm would be kinetic chaos and kinetic continuum, an idea that Sachs borrowed from Plato. Chaotic movement would be something close to a natural phenomenon such as an avalanche, while continuum movement would be something like a smooth gliding of a sailboat. These are extreme cases in which two types of motion result in a sense of no motion, or stagnation.

We can say the Atmosphères and Lontano examples we heard earlier as, respectively, cluster and micro-polyphonic types of sound masses produce a rhythmic experience that tends to a kinetic continuum, since we hear mostly maintenance of sounds with few articulations. [Background music: Ligeti, Lontano].

Even so, in the Lontano example, although the entrances and note articulations are very soft, they in a certain way make us aware of the accumulation process that is going on. Because of that, the kinetic continuum appears to be softened. On the other hand, the Threnody example is closer to kinetic chaos, as it is full of internal and consistent movement. These are totally distinct types of rhythmic experiences.

Another good example of tending to kinetic chaos is the second movement of Three poems, by Lutosławski. Here, the chaos is achieved by a ‘cloud’ of speaking voices. However, in this specific case, the vocal cloud constitutes only one stream, there are also other streams of percussive and wind instruments gestures that evoke a sense of an aperiodic sequence, contrasting with the homogeneous character of the voice cloud.

Ex. 4: Lutoslawski, Trois Poèmes II. [3’25' - 3’40’’]

Considering what has been said, can one deduce that sound masses are, by their own nature, mostly beatless?

I would prefer to say that the composers who started to work on the development of sound masses were also interested in breaking with that notion of rhythm linked to metric structure and duration patterns. In this sense, the absence of a beat seems to be a consequence of the process. Ligeti, for example, said he wanted to suppress rhythm in Atmosphères.

Maybe he did not mean to suppress rhythm, but just the traditional beat-based rhythm.

Yeah, Ligeti, as well as Xenakis and Penderecki, was interested in the construction of global structures, continuous sonorities, whereas the idea of rhythm as made of discrete events forming small recognizable patterns does not fit.

Nevertheless, in some pieces, the sound mass is achieved not exactly by a chaotic or statistical distribution of articulations, but rather by a superposition of fast periodicities. In the next example, from Clocks and Clouds by Ligeti, we can distinguish the presence of fast and periodic motives integrating a global dense texture. This periodicity is probably not sufficient to maintain a steady sense of beat, especially because there is another stream of sustained sounds completing the mass.

Ex. 5: Ligeti, Clocks and Clouds [2’15'‘- 2’50'‘]

Don't you think that the term "sound mass" has been used rather loosely?

I believe that the problem might be related to a certain historical perspective in musicology. What I mean is that, for a long period of time, music was mostly expressed in linear terms. In fact, all of the textural types we referred to earlier, like monophony or polyphony, point to a musical reality where horizontal aspects are central.

It is true, and I think that in a very general way, from the medieval period up to the Baroque, we can broadly speak of music made by lines and their interconnection. Even later, in classical and romantic periods, one can essentially think of music as based on a dominant figure - the melody - against a background - the accompaniment texture. [Background music: Stravinsky, Psalm Symphony, mov. II].

However, in the 20th century, mostly in the second half, some composers started to use new compositional approaches. They began focusing their attention on other aspects, namely timbre, register, articulation, spatialization, dense vertical aggregates, and so on, in the place of more traditional concepts, such as melody or harmony, for example.

I believe that this phenomenon has occurred not only in music, but also in other arts. As the great art historian Heinrich Wolfflin said, and I quote: “There was a shift from a style dominated by linearity, self-contained forms, and clarity, to a style characterized by recessional forms of composition, open forms, and lesser clarity”—end of quote. This may have limited the musical analytical terminology necessary for understanding new musical forms. The thing is that, while in the domain of the plastic arts, for instance, there is a great wealth of textural denominations, it appears that the analytical and theoretical realm of music lags behind other artistic and scientific areas of knowledge, keeping with a linear based discourse for texture description.

Despite the most valuable contributions of authors such as Wallace Berry or Robert Strizich, only in recent years has music with a more textural character begun to gain the attention it deserves, especially music made of sound masses.

Yes. For instance, [Background music: Kevin Drumm, “Runtish ep”] Curtis Road proposes a very interesting taxonomy of cloud sound mass types, associated with real cloud shapes in the atmosphere, which includes cumulus, well-defined cauliflower-shaped cottony clouds, and stratocumulus, blurred by wind motion, etc.

In a similar way, the traditional notion of musical rhythm has not evolved to deal with sound masses and other non-beat-based music. To begin with, as sound masses are often beatless, they do not present periodicities in a way that permits us to entrain with them, like we would entrain to steady beats in a vast number of other musical types. Because of that, sound masses are sometimes described as lacking rhythm completely. This is a fallout of the fact that musical rhythm has been linked to the presence of beats for so long.

However, if we take into consideration the second notion of rhythm, and focus on how music engages us with its motion, changes, gestures, events, and morphological features, allowing us to access the flux of time, we would hardly consider a musical section non-rhythmic. We also need a concept of rhythm to adequately describe continuous motion in music, as the absence of clear articulations might well be a challenge to rhythmic conceptualization. The next excerpt from the orchestral composition Polymorphia by Penderecki, illustrates very well this difficulty.

Ex. 6: Penderecki, Polymorphia, [7'25''-7'51'']

But without underlying beats, our perception of rhythmic structure changes completely, doesn’t it?

Sure! That could also be a reason why non-traditional forms of rhythmic exploration are sometimes not very well accepted by a large audience. Actually, entrainment theories tell us that our brain is molded not just to find periodicity in our environment but also to synchronize with it, tuning neural activity to isochronous external events. Because of that, if music presents aperiodic events that do not allow us to extrapolate steady beats, there will be probably a disappointing feeling or even a lack of attention.

Also, sometimes sound masses are made of sounds so smooth that we cannot hear clear articulations, which can also cause frustration, breaking with our usual conception of music made of discrete events. But I don't want to adopt a strictly deterministic view. The influence of cultural conditioning could be just as significant as biological neural predispositions. What I mean is, everyone hears with their own ears.

No doubt! Besides, in the context of beat-based rhythms, people vary between two types of perception, namely the figural and the metric perception. In the metric perception, people instantly find the basic periodicity, the beats, hidden in a sequence of onsets. By contrast, in the figural perception, people are more aware of the boundaries between groups of onsets, than underlying beats. Children and people with no formal music education tend to perceive rhythms in the figural approach rather than in the metric one. Maybe beatless music leads us to perceive rhythms only in the figural mode, but traditional approaches treat rhythm and meter as essentially interconnected features.

So, the big question is, then, how we can approach non-beat-based rhythms in analytical terms without using the old paradigms built for beat-based music.

Well, rhythm, regardless of being beat-based or non-beat-based, does not exist, like pitch or an instrument's timbre, exist before a composition is created. As musicologist Eytan Agmon said, rhythm is just a consequence of every musical parameter. What could exist a priori are some stereotypical features, like ternary or binary metrics, or style-related duration patterns like march or samba, for example. What we do not have is some shared taxonomy of stereotypical non-beat-based rhythms, for example.

So, it’s the same type of question that we’ve previously discussed about texture and sound masses, I mean, the lack of a shared taxonomy. That is, the situation points out to a much broader problem, namely, how to reconcile historical frameworks with contemporary expressions? This is certainly an issue with regard to musicological studies.

Maybe to approach non-beat-based rhythms, [Background music: Eliane Radigue, Adnos [0’’ - 2’]] we first have to turn to that general concept of rhythm, to the most basic feature of rhythm, which is the sense of movement. If we think of rhythm as movement, we can establish that its opposite is stagnation or stasis, the absence of movement. For example, much of the so-called drone music explores extremely gradual changes over time, these changes often do not transmit any sense of motion. The first two minutes of Adnos by Eliane Radigue have a long, sustained texture with a subtle vibration. It does slightly change over time, but the changes are difficult to locate and specify.

That reminds me of Jonathan Kramer’s concept of vertical tempo is an attempt to describe a non-linear musical situation in which the lack of progression, causal relations, phrases, and motion gives us an experience of timelessness. He says, and I quote: “(vertical time is) a single present stretched out into an enormous duration, a potentially infinite 'now' that nonetheless feels like an instant”, end of quote.

Changing the subject a little bit, how can rhythm and texture be interconnected concepts?

Well, as we said earlier, rhythm depends on every other musical parameter to exist. Sometimes, what we feel as contributing to create rhythm in music is linked to what we would generally describe as texture variations. For example, rhythm can emerge from change and interaction inter and intra textures. The noise genre is especially good at working with this. Let’s hear in the next example from Merzbow two textures interacting: One stable periodic oscillation produced by a low-pitched noise is combined with a smooth, high-pitched complex noise that disturbs it.

Ex. 7: Merzbow, Woodpecker n. 1 [1’’ - 50’’]

On the other side, an example of rhythmic intra texture would be in Ellen Fullman’s Memory of a Big Room. A block of sound gently modulates in frequency, strolling through the tessitura, becoming more or less dense vertically. In this case, the rhythm directly emerges from the morphologic behaviour of the sound mass.

Ex. 8: Ellen Fullman, Memory of a Big Room [1’00 to 2’00'‘]

Additionally, these two kinds of sound masses we have been talking about as tending toward continuum or chaos represent two opposite configurations both rhythmically and texturally. If we start to analyze the internal movement of a chaotic mass, we will find it difficult to separate rhythmic features from textural ones.

This leads us to another important issue to discuss, which is the concept of density, a concept that has been linked both to rhythm as well as to texture in music theory. From a horizontal perspective, we usually talk about density, referring to what Boulez called the occupation index, meaning, how events, articulations, or onsets are distributed over time. As a vertical phenomenon, density has to do with the relative distances between sounds within the sound mass, which strongly contributes to the feeling of texture opacity.

Relating to vertical density, let’s hear two examples, both from Penderecki. The first one is an extremely dense chromatic cluster occupying a two-octave range. The second example is an aggregate revealing a much less internal compression, constituted by only six notes more widely spaced.

Ex. 9 Penderecki, Threnody for the Victims of Hiroshima, [9’08’’-9’35’’]

Ex. 10, Penderecki, The Dream of Jacob, [1’40’’-1’50’’]

And, at last, this is especially relevant if we are talking about non-beat-based music, because in beat-based music, articulations are normally distributed in order to create periodicities, the feeling of the beat gives us the impression that the density is somewhat stable. However, without the beat, density variations become a special kind of rhythmic behaviour.

Well, when rhythm is tending to chaos, density tends to be very consistent. When density varies over time we start to have the experience of an aperiodic sequence, sparse and crowded moments alternating. Now we are going to hear two excerpts, one from La Legende D'Éer by Xenakis, and another from the first Symphony of Penderecki. In the first excerpt, the articulations modulate in density, while in the second one, the saturation of articulations is mostly permanent.

Ex. 11: Xenakis, La Legende D'Éer [4'50''-5'50'']

Ex. 12: Penderecki, 1st Symphony [11'50''-12'10 '']

Very dense, chaotic rhythm can also vary in the degree of proximity between articulations. If we keep intensifying density, we will reach an ambiguous situation where the articulations are described by Roads as, and I quote: “[…] too slow to form a continuous tone but too fast for rhythmic definition.”, end of quote.

In that case, the barrier between tending to chaos or tending to continuum also blurs a little bit. Let's hear one more excerpt from La Legende D'Éer illustrate this.

Ex. 13: Xenakis, La Legende D'Éer [27'15''-27'45'']

We hope this episode has contributed to a reflection on the interconnectedness of rhythm and texture when applied to sound masses. To sum up, our aim was mostly to raise some questions about the nature of sound masses, as perceived in horizontal and vertical aspects. Rhythmic behavior can vary significantly in sound masses, based on the presence or not of articulations and their periodic or aperiodic configuration. Besides, continuous gestures are abundant in beatless music, and they are responsible to evoke movement sensation or, as we tried to defend here, rhythm.

When we use the expressions ‘tending to chaos’ or ‘tending to continuum’ we aim to show that there is a huge gradation before we really reach pure kinetic chaos or continuum. This is not a sink or swim situation. The gradation is affected by degrees of density, morphological features of sounds, consistency or variance of sonic behaviour, and also the nature of concomitant streams composing the overall texture.

Historically rooted in music’s linear forms, our perception could benefit from expanding to encompass non-linear, beatless soundscapes and dense sonic tapestries. Also, our more conventional association of movement with discrete sounds is challenged in the face of continuous motion and rhythmic gestures in much of today's music.

We would like to thank very much the staff of the SMT-Pod for all their valuable and guidance in the presence of Megan Lyons, Jennifer Beavers, Anna Nelson, and Katrina Roush.

Also our thanks to Ernesto Donoso for his lightning comments on the first draft of this podcast. Thank you for listening! Bye!

Bye!

Visit our website smt-pod.org for supplemental materials related to this episode and to learn how to submit your own episode proposal. Join in on the conversation by tweeting your questions and comments about this episode @SMT_Pod. SMT Pod's theme music was written by Zhangcheng Lu with closing music by David Voss. Thanks for listening!