Twelve-note composition.

A method of composition in which the 12 notes of the equal-tempered chromatic scale, presented in a fixed ordering (or series) determined by the composer, form a structural basis for the music. It arose in the early years of the 20th century, when the dissolution of traditional tonal functions gave rise to several systematic attempts to derive a total musical structure from a complex of pitch classes that are not functionally differentiated. Skryabin’s Seventh Sonata (1911–12), for example, is based upon such a complex, or ‘set’ (ex.1). The set, at any of its 12 transpositional levels, generates both the melodic and the harmonic elements of the composition. It is defined in terms of its pitch-class content, relative to transposition, and no pre-compositional ordering or segmentation of the set is assumed. Clearly there is only one analogously unordered set of all 12 pitch classes. About 1920 Hauer and Schoenberg independently arrived at concepts of 12-note set structure that make it possible to differentiate between one 12-note set and another, and among transformations and transpositions of any given 12-note set.

See also Atonality and Serialism.

1. 12-note tropes.

2. 12-note series.

3. Origins of the 12-note set.

4. 12-note composition.

5. Pre-compositional structures.

6. 12-note ‘tonality’.

7. Extensions and developments of 12-note composition.

8. Conclusion.

BIBLIOGRAPHY

PAUL LANSKY, GEORGE PERLE (text), DAVE HEADLAM (bibliography)

Twelve-note composition

1. 12-note tropes.

In Hauer’s system the 12 pitch classes are divided into discrete, mutually exclusive segments. The order of segments within a 12-note set and the order of pitch classes within each segment are not pre-compositionally defined. Each such set and its 12 transpositions represent what Hauer called a ‘trope’. The only tropes that Hauer investigated systematically are those that divide the pitch classes into two hexachords. Let the integers 0 to 11 represent the successive pitch classes of an ascending chromatic scale of unspecified transposition. If pitch-class numbers 2, 3, 5, 7, 9 and 10 are chosen as one hexachord, the trope will be completed by the hexachord formed by the remaining pitch classes: 0, 1, 4, 6, 8 and 11. The hexachords (8, 9, 11, 1, 3, 4) and (6, 7, 10, 0, 2, 5) are a representation of this same trope since they are its transposition by a tritone of (i.e. the addition of ‘T-no.6’ to) each element of the original. Hauer demonstrated that there are 80 non-equivalent hexachords. Eight of these will each form a trope by combination with its own transposition. (For example, the whole-tone hexachord (0, 2, 4, 6, 8, 10) may be combined with a transposition of itself by any odd T-no.) The remaining 72 hexachords are paired to form 36 tropes, and so there are 44 independent hexachordal tropes.

Hauer’s is the earliest known attempt at any general formulation of the resources of a 12-note sound world. His concept of hexachordal tropes was a remarkable anticipation of subsequent developments in 12-note composition and theory. It is doubtful, however, that he had any direct influence on what is significant in these developments. His own compositions are simple-minded exercises, and his 12-note theory was embedded among mystical and megalomaniac assertions. The fact remains, however, that he was the first to discover the all-important principle of segmentation – the partitioning of the collection of 12 pitch classes into mutually exclusive sub-collections – as a basis for classifying the pitch-class material of 12-note music.

Twelve-note composition

2. 12-note series.

If the 12 pitch classes are regarded as an unsegmented collection, sets can be differentiated only by the ordering of their elements. In Schoenberg’s system ordered sets (‘series’ or ‘rows’) that may be transformed into one another by transposition (i.e. the addition or subtraction of a constant T-no., mod 12), by retrograding, by inversion (i.e. the subtraction of each of the original pitch-class numbers from a constant T-no., mod 12) or by any combination of these operations, are all regarded as different forms of a single series. Since the series in each of its aspects – prime (P), retrograde (R), inversion (I), retrograde-inversion (RI) – may be stated at 12 transpositional levels, there will be 48 set forms in the complex generated by a single series.

Twelve-note composition

3. Origins of the 12-note set.

The term ‘12-note music’ (or ‘dodecaphony’) commonly refers to music based on 12-note sets, but it might more logically refer to any post-triadic music in which there is constant circulation of all pitch classes, including both the pre-serial ‘atonal’ compositions of Schoenberg, Berg and Webern and the ‘atonal’ compositions of Skryabin and Roslavets based on unordered sets of fewer than 12 elements (see Atonality). However, the customary sense is retained here. Occasional systematic statements of the 12 pitch classes first appeared in the music of Berg. A 12-note series is one of the principal themes of his Altenberg songs, composed in 1912, about three years before Schoenberg’s first experiment with ‘a theme consisting of the 12 notes’ in his unfinished oratorio Die Jakobsleiter. Schoenberg’s ‘theme’ is a hexachordal 12-note trope, rather than a series. By summer 1919 Berg had completed, in short score, the first act of Wozzeck, which contains a 12-note passacaglia theme that is often cited as an adumbration of the Schoenbergian series. Non-serial 12-note collections are found in Berg’s works throughout his career. In the concluding song of op.2 (1910) a white-key glissando in the left hand of the piano part occurs simultaneously with a black-key glissando in the right, a 12-note aggregate which anticipates by about 20 years the white-key and black-key clusters of the Athlete’s leitmotif in Lulu. A chord consisting of all 12 pitch classes opens and closes the third of the Altenberg songs. The two mutually exclusive whole-tone scales and the three mutually exclusive diminished 7th chords generate 12-note collections in Wozzeck. Other examples can be cited from Wozzeck and the Drei Stücke for orchestra (1914–15).

Schoenberg has explained the concept of a 12-note series as originating in the desire to avoid excessive pitch-class repetition in atonality, citing in this connection the tendency to avoid the octave in atonal compositions. Webern apparently anticipated both Schoenberg and Berg in this respect, consistently avoiding octave doublings as early as 1910 in his Zwei Lieder op.8. In a lecture given in 1932 (published in 1960) he described his early intuitive approach to the concept of the 12-note series:

About 1911 I wrote the Bagatelles for string quartet (op.9), all very short pieces, lasting a couple of minutes – perhaps the shortest music so far. Here I had the feeling, ‘When all 12 notes have gone by, the piece is over’. Much later I discovered that all this was a part of the necessary development. In my sketchbook I wrote out the chromatic scale and crossed off the individual notes. Why? Because I had convinced myself, ‘This note has been there already’. … In short, a rule of law emerged; until all 12 notes have occurred, none of them may occur again. Were this ‘rule’ to be strictly applied the 12 pitch classes would be continually reiterated in the same order within a movement, thus forming a repeating series.

The principle of non-repetition, however, is clearly not a sufficient explanation of the serial concept. One of the characteristic features of a melodic theme in tonal music is, after all, the order assigned to its pitches, but this feature is inseparable from others – rhythm, contour, tonal functions – any and all of which may be varied within certain limits without destroying the identity of the theme. The interdependence and interaction of these elements are far more ambiguous and problematical in atonality. The pitch-class content of a group of notes may be exploited independently of its other components, and in one of Schoenberg’s last pre-dodecaphonic works, the first of the Fünf Klavierstücke op.23, the pitch-class order of the initial melodic line is treated as an independent referential idea (ex.2). The melodic figure which begins the second piece of the same opus serves as nothing less than an ordered set, though it is only one of the sources of pitch-class relations. Both pieces were completed in July 1920. A month later Schoenberg was at work on op.24 no.3, the Variation movement of the Serenade. This is the earliest example of an entire movement exclusively based on a totally ordered – though not yet 12-note – set. The 14-note series, comprising 11 pitch classes of which three occur twice, is employed in all four aspects, but there is no change in the initial transpositional level (as there is in op.23 no.2). The earliest 12-note serial piece, the Präludium of the Piano Suite op.25, was composed during the period 24–9 July 1921. The series, sole source of pitch relations, is employed in all four aspects and at two transpositions separated by the interval of a tritone. Since the tritone, which is invariant in its pitch-class content under transposition by a tritone, is significantly represented in the structure of the set, important invariants are generated between the different set forms.

On completion of the first movement of the Suite, Schoenberg took up the Serenade again. The first movement, evidently composed in one day (27 September 1921), is largely based on the concept of strict inversional complementation, though in a non-serial context. Work on the Fünf Klavierstücke op.23 was resumed on 6 February 1923 and completed in less than a fortnight. No.3, based on a five-note set, is an extraordinarily complex study in the structural implications of inversional complementation and invariant relations. The concluding piece, however, Schoenberg’s second 12-note serial piece, seems primitive and naive in its constant reiteration of the initial set form, as compared with his first piece in the system, composed almost two years earlier. The same may be said of the only 12-note serial piece of op.24, the Sonett, composed a few weeks later. Meanwhile, between 19 February and 8 March, Schoenberg composed the five remaining movements of the Piano Suite, basing all of them on the same set and the same procedures as the first movement, and thus asserting, for the first time, all the basic premises of his 12-note system.

Of the remaining movements of op.24, completed in March and April 1923, only portions of no.5, Tanzscene, are based on a 12-note set. The first 57 bars, dating from August 1920, make no use of anything that may be termed a set, but on taking up this movement again on 30 March 1923 Schoenberg converted the pitch-class content of the initial six-note motif into one of the hexachords of a 12-note trope, supplied the missing hexachord to complete the trope and used this as the basis of the newly composed contrasting sections of the piece. (Schoenberg had experimented with a hexachordal trope in 1915, and there is no reason to assume that he was influenced by Hauer’s theory.) A tritone transposition of either hexachord of the trope of the Tanzscene (ex.3) leaves the pitch-class content of the hexachord unchanged, a property exploited by transpositional relations in the work. The Tanzscene points forwards to one of Schoenberg’s late works, the Ode to Napoleon (1942), which is also based on a trope (self-transposable at T-no.4 and T-no.8), rather than a series.

Twelve-note composition

4. 12-note composition.

It is one thing to define a 12-note set and quite another to define 12-note composition. A general definition cannot go beyond the assertion that all the pitch-class relations of a given musical context are assumed to be referable to a specific configuration of the 12 pitch classes, a configuration that is understood to retain its identity regardless of its direction or transpositional level. Problems arise with the definition of that context and with the compositional representation of the rules of set structure.

With regard to the first question, Schoenberg noted: ‘It does not seem right to me to use more than one series [in a composition]’. Of the three Viennese masters, only Webern, beginning with op.19, unambiguously observed this principle. It is completely inconsistent with Berg’s practice, even within any single movement. Schoenberg’s implied definition of a ‘series’ does not include cyclical permutations as representations of a given series, but Berg made use of these regularly. Almost every movement in which he can be said to employ some sort of 12-note method contains ‘free’, that is non-dodecaphonic, or at least non-serial, episodes. And even the 12-note sections of such movements are often based on two or more independent sets – independent in the sense that no form of one set can be transformed into any form of another by transposition, inversion, retrogression, cyclical permutation or any combination of these operations. The first movement of the Lyrische Suite is based on not one but three sets. All three, however, are representations of the same trope (ex.4). (In the notation of set forms in the examples that follow, each accidental affects only the note it precedes.) The principal set is a serial representation of this trope (ex.5). Another series is derived by reordering the hexachordal content of ex.4 as a circle of 5ths (ex.6). Finally, the conjunct version of the trope is itself employed compositionally, not only in the form shown in ex.4, but also with various cyclical permutations of the hexachords, as in ex.7. The last movement of the Lyrische Suite simultaneously employs two different series throughout. In order to understand their relationship one must include the characteristic contour assigned to each series among its essential attributes. The initial series is partitioned into two segments in terms of the registral distribution of its elements, as shown by stemmed and unstemmed notes in ex.8, and these form a second series (ex.9).

Schoenberg’s own practice can be said to conform to his rule of the unique series only if the term ‘series’ or ‘row’ is replaced by ‘set’ and if the latter is considered only partially defined by the serial ordering. The first completely 12-note work, the Piano Suite, op.25, employs a series that is partitioned into three four-note segments, and these are employed simultaneously as well as successively. Thus the set cannot be properly defined exclusively in terms of its total serial ordering. A single referential ordering can be deduced in this and in most of Schoenberg’s other 12-note compositions, but this ordering tends to be secondary to another attribute of Schoenberg’s sets: their segmental pitch-class content. The Third String Quartet and the String Trio are exceptional in that each employs several distinct series. If the set of the former, however, is defined as consisting of an invariably ordered five-note segment and a variably ordered seven-note segment, and that of the latter as consisting of two variably ordered six-note segments, each work may be said to be based upon a single set.

Even where a single unambiguous pre-compositional serial ordering of the set is assumed, the moment the series is used compositionally there are inevitable ambiguities. The presence of another structural attribute, in addition to that of serial order, is almost always implied: the partitioning of the series into segments. It has been shown (exx.4–6) how a set segmented into two unordered hexachords provides the basis for the association of three independent derived sets. In general, segmentation is used as the basis for the association of set forms chosen from the 48 members of the complex generated by a single series. The first movement of Webern’s Second Cantata op.31, for example, employs the following forms (ex.10) and their respective retrograde versions (R0 and RI0). (The level of a set form is indicated by a subscript integer; that assigned to any P or I form of an ordered set is the same as its initial pitch-class number, and that assigned to an R or RI form will be the same as its final pitch-class number; in the rest of this article pitch-class numbers 0 to 11 represent the successive elements of an ascending chromatic scale beginning on C.) Each hexachord holds five pitch classes in common with the given inversionally complementary hexachord, as shown in the example. Were P to be paired with any other transposition of I, there would be less than five elements in common between corresponding hexachords. The manner in which the hexachords are compositionally stated supports the assumption that the association of inversionally complementary segments is motivated by their maximum invariance of content.

The series on which the 12-note sections of the third movement of Berg’s Lyrysche Suite are based begins with a four-note segment whose reordered content recurs in transposed or inverted forms within the series. The set forms given in ex.11 convert each of the reordered segments into the pitch-class collection of the initial four-note segment of P10. (In the composition P8, I3 and P5 are cyclically permuted to commence or conclude with the invariant segment.)

The series of Webern’s Concerto op.24 is segmented into subsets which are themselves forms of a three-note series. P11 and RI0, the first two set-form statements, present subsets of identical pitch-class content in the same relative positions within each set form (ex.12).

The series of Webern’s Symphony op.21 consists of two hexachords related as p0 to r6 (ex.13). Thus each P form of the set is equivalent to the tritone transposition of its retrograde, and the corresponding relation will hold between I and RI forms. For this, as for any ‘symmetrical series’ (any series comprising two hexachords related as pn to rn+6 or pn to rin+(2x+1), there are 24, rather than 48, non-equivalent set forms.

From 1928 Schoenberg systematically employed hexachordal segmentation as a basis for the association of set forms. In the Fourth String Quartet, for example, P2 and I7, or any other pair of equivalently related set forms, may be combined so that corresponding hexachords (vertically aligned for illustrative purposes inex.14) produce all 12 pitch classes. Set-form association based on such aggregates of the 12 pitch classes, known as combinatoriality (seeSet), is the governing structural principle in Schoenberg’s 12-note music. The P/I combinatoriality illustrated in ex.14 is only possible where the two hexachords of the series are inversionally complementary in content. If the series of ex.14 is rewritten as a hexachordal trope (ex.15), it is clear that P2, I7 and their retrograde forms R2 and RI7, the four primary set forms of the work, are all members of the same trope.

What Babbitt has called an ‘all-combinatorial’ set permits P/RI as well as P/I combinatoriality. Although Webern did not observe Schoenberg’s principle that combined set forms must produce 12-note aggregates, the series of his Concerto is an example of an all-combinatorial set. If P11 of ex.12 is considered as a hexachordal series, it is evident that it may be paired combinatorially with I4, RI2, P5 or R11. (The last is a trivial instance, since any series will, by definition, form 12-note aggregates with its own retrograde.) Since transpositions of each of these set forms by the addition of T-no.4 merely reorders the hexachordal content, P11 may also be paired with I8 or I0, RI6 or RI10, P9 or P1 and R3 or R7.

Where corresponding hexachords of a pair of set forms are mutually exclusive, as in ex.14, the contents of non-corresponding hexachords will, of course, be identical. In the music of Berg set forms are associated through this invariance of segmental content. The principal pair of P and I set forms of the basic series of Lulu is shown in ex.16. Transpositions at the tritone will interchange the contents of the two hexachords. Progression among set forms, including members of independent complexes of set forms, may be referred principally to degrees of invariance of segmental content. Schoen’s series and Alwa’s series are associated through the set forms shown in ex.17, which are trichordally as well as hexachordally invariant with each other.

The principal set forms of Alwa’s series, P4 and P9, are maximally invariant (five elements in common) with the basic series at P0 (or I9), as illustrated in ex.18.

Where a set is strongly characterized by segmental content as well as serial ordering in the music of Schoenberg and Berg, linearly stated set segments – functioning as ‘broken chords’ in a sense – often depart from the assumed ordering. In Schoenberg’s Klavierstück op.33a, for example, though one can deduce an ordering for the set, segmental content is a far more significant property, and in the Ode to Napoleon it is the only defining property of the set. The numerous sets found in Berg’s Lulu include series, tropes based on various types of partition, ‘serial tropes’ (i.e. sets whose segments are subjected, independently of the set as a whole, to such serial operations as will not revise their respective contents) and ‘harmonic tropes’ (i.e. sets partitioned into segments of an essentially chordal, rather than linear, character).

In Schoenberg’s 12-note works the combinatorial relation between P and I or R and RI set forms is preserved by maintaining a constant difference in the respective transpositional levels of the associated set forms. In op.33a, for example, the succession of T-nos. is as follows: P/R 10 0 5 10 I/RI 3 5 10 3 Webern sometimes used the opposite procedure: the maintenance of a constant sum between T-nos. of associated set forms. In the first movement of the Quartet op.22, for example, inversionally complementary set forms are paired as follows: P1 P7 P1 P10 P11 R0 P0 R1 P7 P7 R1 I11 I5 I11 I2 I1 RI0 I0 RI11 I5 I11 RI11 The sum of T-nos., 0, mod 12, remains the same throughout. The principal set forms of the second movement are P6, I6, R6 and RI6, and so here too the sum of complementary T-nos. is 0, mod 12. The significance of this procedure is that it preserves exactly the same pairs of inversionally complementary pitch classes, whatever the respective transpositional levels of the set forms. These complementary relations are shown in ex.19 for this case. In Schoenberg’s op.33a, on the other hand, the complement of any given pitch class is different for each pair of T-nos.

Twelve-note composition

5. Pre-compositional structures.

The concepts of segmentation and inversional complementation permit a generalized description of pitch relations for 12-note music. The special properties that derive from the hexachordal organization of a given series are shared with all other serial representations of the same trope, and a series based on any other type of segmental organization may be similarly regarded as a special instance of a single pre-compositional structure. The series of Schoenberg’s Fourth String Quartet (ex.14) is one of 518,400 (= (6!) (6!)) series that may be derived by reordering the elements of each hexachord of the trope in ex.15. All of these series share the structural functions that depend upon hexachordal content alone. Whatever the series, the content of each hexachord of any given P form will be duplicated in the content of the non-corresponding hexachord of one I form. The same property characterizes every series that may be derived from any of 12 other tropes. Thus 13 of the 44 tropes may be grouped together as a family, and almost every one of Schoenberg’s 12-note works is based on a serial representation of one of these. (The 13 tropes of the ‘Schoenbergian’ type are numbered 14 to 26 under ‘Six-Note Collections’ in the appendix to Perle, 1962, rev.6/1991.)

The hexachordal trope illustrated in ex.4 is represented by the basic series of Lulu (ex.16), as well as by the three sets on which the first movement of the Lyrische Suite is based (exx.4–6). This trope is one of six (numbered 1 to 6 in Perle) characterized by the following properties: the relative pitch content of both hexachords is the same, that is each can be converted into the other by transposition; each hexachord is invariant under inversion, and therefore also an inversion as to unordered content of the other hexachord (since the two are transpositionally equivalent as to content). The all-combinatorial series are representations of these six tropes. Transposition by a perfect 5th above or below of any series derived from ex.4 preserves maximum invariance of hexachordal content between identical aspects of the series (five common elements), and in Lulu Berg made significant use of the resulting hierarchy of harmonic areas. The series on which the third of Schoenberg’s Drei Lieder op.48 is based preserves total invariance of content either between corresponding or between non-corresponding hexachords for all set forms of the complex, since it is a representation of the trope whose hexachords are the two non-equivalent whole-tone collections. All transpositions of this trope are equivalent, since transpositions do not alter the segmental content of the trope but merely interchange the two segments.

Any given 12-note set form is one of 479,001,600 (=12!) permutations of the chromatic scale. Symmetrically related dyads are generated when equivalent permutations of two contrary chromatic scales are aligned. Ex.20 shows two such, intersecting at C and F (intersections will always occur at two points separated by the interval of a tritone; the ascending scale will be termed a ‘P cycle’ and the descending scale an ‘I cycle’). The dual axis of symmetry of each dyad will then be C and F, which is to say that the members of each dyad will be equidistant in opposite directions from C, and likewise from F. The axis of symmetry may be conveniently represented by the sum of pitch-class numbers that represent the members of any dyad. (In this instance that sum is 0, mod 12.) The interval classes generated by the aligned cycles may consistently be represented by the number, mod 12, obtained by subtracting the pitch-class number of each element of the I cycle from that of its complementary element in the P cycle. Inversionally complementary set forms whose T-nos. are 0 and 0, 1 and 11, 2 and 10, 3 and 9, 4 and 8, 5 and 7, and 6 and 6 will permute the vertical intervals of ex.20, but the pair of pitch classes that constitute a given interval class remains the same, since the sum in each instance is 0, mod 12. All of these T-no. pairs except 4 and 8 are represented in Webern’s Quartet op.22 and are the basis of its tonal structure and formal design. The opening and closing sections of the first movement of the Symphony op.21, and the middle movement of the Piano Variations op.27, are limited to paired complementary set forms of sum 6.

Any realignment that displaces one of the two cycles of ex.20 by an even number of semitones transposes the same collection of intervals. The association of inversionally complementary hexachords to form 12-note aggregates, as in most of Schoenberg’s 12-note compositions, is only possible where the sum of T-nos. is odd, since otherwise there must be pitch-class duplication at two points. If the diverging chromatic cycles are aligned so that the sum of complementary pitch classes is odd, the interval classes that contain an odd number of semitones are produced and pitch-class duplication is eliminated. The principal pair of set forms of Schoenberg’s Fourth String Quartet (ex.14) generates the dyadic relations shown in ex.21.

The symmetrical pitch relations produced by the one-to-one alignment of complementary chromatic cycles should not be confused with thematic inversion in earlier music. The harmonic and tonal context within which themes and motifs are sometimes ‘inverted’ in diatonic music exists before and apart from the operation of inversion. Thematic inversion in a diatonic context is not literal since complementation is not measured in terms of a single unit, the semitone, as it is in the 12-note system, and the functional properties of the diatonic system are not reflected by inversion, which would require that the function of the root of a major triad be assignable to the 5th of a minor triad and that the degree functions of a major scale be assignable to the symmetrically complementary degrees of a retrograde Phrygian scale.

Strict inversional complementation has been significantly employed in non-diatonic music apart from the 12-note system: the first-movement exposition of Schoenberg’s Serenade op.24 is exceptional in that it is as rigorously and consistently employed there as it might be in a 12-note serial work. The periodic formal design is entirely dependent upon inversional procedures and all pitch relations are based on a single sum of complementation. Perhaps the most sophisticated use of inversional complementation is to be found in some of the works of Bartók, particularly the Fourth String Quartet. Here there is modulation from one sum of complementation to another via pivotal elements (primary among these is the tetrachordal structure illustrated in ex.22, the inversional relations of which may be interpreted in two different ways); differentiation of harmonic areas through the simultaneous or successive juxtaposition of dyad collections representing different sums; differentiation through the juxtaposition of progressions which preserve constant intervallic differences with progressions which preserve constant sums; the combining of small-scale, non-symmetrical progressions into large-scale symmetrical progressions; the use of axes of symmetry as tone centres and so on. It is obviously necessary to discuss such a work in the same context as the 12-note music of Schoenberg, Berg and Webern, although Bartók did not use 12-note series. The basic cell of the quartet (ex.22) is also the basic cell of Berg’s 12-note opera Lulu and generates the set – a tetrachordal trope – with which that work begins (ex.23). The role assigned to this trope in the opera is explained by its special character: it may be inverted at any odd T-no. or transposed by any even T-no. without change to its tetrachordal pitch-class content. The intervallic properties (deriving from the presence of the tritone) that explain the function of this tetrachord in Bartók’s Fourth String Quartet are also those that explain its function in Berg’s opera.

Wherever there is inversional symmetry based on the chromatic scale, one of two ‘modes’ is expressed (the one producing only odd, the other only even intervals), and that ‘mode’ occurs in one of its six ‘keys’ (the six sums that represent the different transpositional levels of the collection of symmetrically related intervals). All intervals and sums are given in the two arrays shown in ex.24; Even array and ex.24; Odd array. Dyads of the same sum class are in the same column and dyads of the same interval class in the same row. Each row of intervals is continued in the equivalent row (1/11 in 11/1 etc.); each column of sums is continued in the same column read in the opposite direction from the point of intersection (intervals 0 and 12, or 1 and 11). Any symmetrical collection, regardless of the number of its elements, can be analysed into dyads that will lie in the same column. Symmetrical tetrachords of two dyads of sum 9, which play a significant role in Bartók’s Fourth String Quartet, will be formed by any pair of dyads in the 9 column, as for example C–A and E–F, with which the work opens. The same tetrachord may be read as the interval pair C–E and A–F in the 4 or 8 row, or as the interval pair C–F and E–A in the 5 or 7 row. The compositional process in the first movement is largely an unfolding of the implications of such reinterpretations of tetrachordal collections. The principal series of the first movement of the Lyrische Suite (ex.5) is not only a representation, as noted above, of a particular hexachordal trope, but also a representation of the collection of dyads of sum 9. These are compositionally articulated in the initial thematic statement of the series (ex.25) and again in a cyclic permutation of that statement (ex.26).

The opening section of Webern’s Symphony demonstrates the simultaneous representation of different sums of complementation. The contrapuntally associated set forms, P9 and I9, I5 and P1, I0 and P6, and P2 and I4, are sum 6 complements. Although the series is of the Pn=Rn+6 symmetrically ordered type, which implies hexachordal segmentation (ex.13), it may also be segmented into inversionally symmetrical tetrachords that are invariant as to content between Pn and In+3. The eight set forms unfold a double inverted canon in which each voice consists of successive set forms that conform to this relation: canon 1: P9 I0 I9 P6 canon 2: I5 P2 P1 I4 This aspect of the set structure is clearly articulated through the assignment of an invariant timbre for each invariant tetrachordal collection in canon 1 (ex.27). (Complementary pitch classes are beamed together in the example.) The complementary pitch classes are adjacent to each other in the outer tetrachords. The middle tetrachord is identical with that illustrated in ex.22. Unlike the others it has two sums of complementation, and the alternative sum maintains invariant two-note segments (ex.28).

Twelve-note composition

6. 12-note ‘tonality’.

Exx.20–21 show how any alignment of two contrary chromatic scales produces all the odd or all the even intervals around a single odd or even axis of symmetry. An equivalent result is produced by alignments of diverging cycles of 5ths. The sum 9 dyads within each hexachord of the basic set of the Lyrische Suite are explicitly generated in this way (ex.29). Where the second hexachord of the principal set (ex.5) is directly followed by its first hexachord – as happens occasionally in the Lyrische Suite and regularly in Berg’s song Schliesse mir die Augen beide, which is based on the same set – the alternate notes of the set completely unfold the diverging cycles. A continuation of the cycles produces the retrograde form of the same set and pitch-class repetition at the point where the cycles intersect (ex.30). Berg’s series, when read as in ex.30, displays a significant property that is not found in the general Schoenbergian set: the elements immediately adjacent to any member of the set (these will be termed the ‘neighbour notes’ of the given axis note) always form the same interval, a perfect 5th in this instance, with the respective transpositional levels of this interval inversionally complementary to the respective transpositional levels of its axis note (ex.31).

The vertically stated pitch-class collections in ex.31 comprise all the three-note segments contained in the set form illustrated in ex.30. The verticalization of set segments is the fundamental means of forming chords in 12-note music and derives from pre-12-note atonal practice, where referential pitch-class collections often occur as simultaneities as well as linear details. However, the collection of chords generated by the verticalization of segments of the general Schoenbergian set provides no basis for a total, systematic control of the harmonic dimension, as this procedure does when applied to cycles and to sets derived from cycles as in ex.30. Suppose, for example, that the verticalized segments of ex.31 were combined with corresponding verticalized segments of an inverted form of the same set (ex.32). The combined segments will yield a series of symmetrically related chords (ex.33). If the axis-note dyads are transposed, the combined neighbour-note dyads will be equivalently transposed in the opposite direction. Thus if any given axis-note dyad occurs at all of its transpositional levels, so will its neighbour-note chord at the complementary transpositional levels (ex.34). Wherever the axis-note dyad is identical in pitch-class content with a dyad segment of one of the two sets, the neighbour-note chord will be identical in pitch-class content with a tetrachord segment of the other set (see asterisked items in ex.34).

Any interval may be used to generate cyclic sets analogous to ex.30. Ex.35 shows diverging cycles of minor 3rds, intersecting so as to yield adjacencies of sum 9 as in ex.30. (The set must be partitioned into two subsets in order to produce the complete collection of such dyads.) The verticalization procedure may be applied to such sets to generate series of pitch-class collections analogous to those illustrated above, with the new cyclic interval replacing the cyclic interval of the perfect 5th in each such collection. There is nothing to prevent the association of set forms, generated by different cyclic intervals, to produce neighbour-note chords based on two different intervals. Through the use of such sets all possible verticalizations may be systematically formulated.

The cyclic set is an ordered unfolding of a complete collection of symmetrically related dyads such as is illustrated for dyadic sums 0 and 9 respectively in exx.20–21. The pair of diverging semitonal scales that generates the sum-9 complementary relations of Schoenberg’s Fourth String Quartet is equally relevant to the first movement of Berg’s Lyrische Suite and to the first movement of Bartók’s Fourth String Quartet. In a certain sense they can be said to be in the same ‘key’. The replacement of a diatonic scale of unequal steps and functionally differentiated notes by a semitonal scale of equal steps and functionally undifferentiated notes completely transforms the meaning of inversion, which becomes a pre-compositional means of symmetrically partitioning the tone material, rather than a means of composing in a harmonic context that is already given. Symmetry, as represented by both the cyclic divisions of the octave and the inversional complementation of pitch classes, is thus an inherent property of the 12-note scale. In the first movement of the Lyrische Suite this property is mapped into the structure of the 12-note series itself.

In Le cru et le cuit Lévi-Strauss challenged Boulez’s defence of ‘serialism’ as a new kind of musical thought which, ‘operating in accordance with a particular methodology, creates the objects it needs and the form necessary for their organization, each time it has occasion to express itself. … There is no longer any preconceived scale or preconceived forms – that is, general structures into which a particular variety of musical thought can be inserted’. Lévi-Strauss insisted that there must be a ‘first level of articulation, which is as indispensable in musical language as in any other, and which consists precisely of general structures whose universality allows the encoding and decoding of individual messages’. For Lévi-Strauss that ‘first level of articulation’ is provided by ‘the hierarchical structure of the scale’, by which he meant the diatonic scale and its triadic functional relations. Schoenberg, too, seems to have assumed that a ‘first level of articulation’ was a prerequisite for a musical language. In the article ‘Problems of Harmony’, after a tendentious and ill-informed attempt to derive the 12-note scale from the overtone series, he concluded that ‘should this proof be inadequate, it would be possible to find another. For it is indisputable that we can join twelve notes with one another and this can only follow from the already existing relations between the twelve notes’. The symmetrical implications of the semitonal scale can serve as the ‘first level of articulation’ of a 12-note musical language, that is as the source of ‘the already existing relations between the twelve notes’.

Twelve-note composition

7. Extensions and developments of 12-note composition.

The influence of Schoenberg’s 12-note system in Germany and Austria before World War II was largely limited to his students and, in turn, to their students. Krenek was perhaps the only widely known composer outside this circle to adopt the system, on which he based his opera Karl V (1933). Under the regimes of Hitler and Stalin a ban was placed on what was represented as an expression of ‘Jewish Bolshevism’ on the one hand and ‘bourgeois decadence’ on the other, and even where there was no political suppression, neo-classicism came more and more to dominate composition from the late 1920s until the end of the war. Immediately after the war, however, there was an astonishingly rapid and widespread growth of interest in the work of Schoenberg, Berg and Webern, and by the end of the 1950s there remained few composers in the USA or western Europe who were not in some way influenced by the concepts of 12-note composition.

Stravinsky’s adoption of serial procedures was remarkable not so much because his position in the musical world had been regarded as diametrically opposed to Schoenberg’s, but rather because of the way in which he was able to integrate these procedures into his own musical language. This is clearly evident in his In memoriam Dylan Thomas (1954), one of the most strict of Stravinsky’s early serial pieces. The work is based on a five-note set, E, E, C, C, D. This use of a five-note set, under transposition and the four transformations of the 12-note system, differs from Schoenbergian serialism mainly in that every transformation does not necessarily contain different permutations of the same collection of pitch classes. Characteristic features of Stravinsky’s earlier music remain, but they appear in a new context: the recurrent motivic statements of the set and emphasis on certain pitch successions such as E–E to emphasize cadential points; the chromatic filling-in of an interval, a major 3rd, with successions of only ascending or descending semitones or minor 3rds (compare the passage in The Rite of Spring at no.130, where an interval of a tritone is filled in by the alto flute using only major 2nds, minor 3rds and major 3rds); and the rhythmic alteration of similar pitch configurations in the strings at the opening of the song and at nos.2, 4 and 8 (compare the oboe solo at the beginning of the second movement of the Symphonie de psaumes).

In his later works Stravinsky more thoroughly incorporated traditional 12-note concepts while still achieving Stravinskian results. The set of Movements (ex.36), for example, is all-combinatorial, but it is not used to form 12-note aggregates. Instead Stravinsky concentrated on the high degree of trichordal segmental redundancy within hexachords. The trichords formed by elements in ordinal positions (0, 1, 2), (3, 4, 5) and (8, 9, 10) (where 0 denotes the ordinal position of the first note of the set) are of transpositionally or inversionally equivalent content, as are the trichords in ordinal positions (2, 3, 4), (6, 7, 8) and (9, 10, 11). This kind of redundancy is particularly Stravinskian, and the motivic use of these trichords generates a musical surface with precisely the kinds of intervallic repetition and emphasis found in the earlier serial works, such as In memoriam.

In later compositions Stravinsky independently reinvented a procedure of hexachordal rotation and transposition that Krenek had employed in 1941–2 in Lamentatio Jeremiae prophetae. An ‘array’ for Abraham and Isaac (1963), for example, is derived by aligning hexachordal rotations of a single transposition of a set: G G A C C A B D D E F F G A C C A G D D E F F B A C C A G G D E F F B D C C A G G A E F F B D D C A G G A C F F B D D E A G G A C C F B D D E F This array is used as a basis for lineal and vertical relations. Stravinsky also constructed an array in which each successive rotation is transposed so as to begin on the same pitch class as the first. This provides a succession of simultaneities whose properties are derived from the structure of the set but whose local characteristics appear quite different from those of the set itself. In the following array this procedure is applied to the first hexachord of the set: G G A C C A G A B C G F G A A F E F G G E D D F G D C D E F G F F G A B (Pitch-class repetitions in columns occur as a function of interval duplication by pairs of pitch classes with the same differences in ordinal positions within the original hexachord. Within each hexachord the columns whose ordinal positions are complementary to 6 (with the initial column as 0) are symmetrical inversions of each other as to pitch-class content, with G as the axis of symmetry.

Many postwar developments involved an extension of the serial concept to control and interrelate the various dimensions of a composition – rhythm, pitch, timbre, dynamics, articulation and so on – in a more precise and highly determinate way. Such processes were foreshadowed in the music of Schoenberg, Berg and Webern. In Webern’s Symphony op.21 and Concerto op.24, rhythm, register and orchestration are organized in such a way as to project and clarify transformations and properties of pitch and pitch class. The set of the Concerto (ex.12) has the property that certain transformations will individually permute each of its trichords. In the opening bar each trichord is assigned a different instrument and rhythm, and in bar 4 the piano’s statement of RI0 – a transformation which retrogrades each of the individual trichords and retains their original order within the set – retrogrades the rhythm and places pitch classes in the same registers as in bars 1–3, thus projecting and interpreting these invariant relations (ex.37). In the opening of the Symphony pitches are assigned symmetrically around a. In the canonic pairing of P and I sets at the beginning of the composition, P9 and I9, and P1 and I5, corresponding pitches in these inversionally related, matched sets are thus symmetrically deployed around a.

The earliest instance of a strictly serially derived duration set is in the third movement of Berg’s Lyrische Suite. The set consists of two subsets (ex.38 shows the relative points of attack) derived by partitioning the pitch set in terms of the registral distribution of its elements (ex.39).

It was not until after the war that the first attempts were made to generalize the application of serial structure by systematically transferring the attributes of a pitch set to the non-pitch elements. The first composer systematically to apply serial procedures to rhythm was Babbitt, in the Three Compositions for Piano (1947). Serial operations have also been applied to dynamics, instrumentation and register (see Serialism).

Twelve-note composition

8. Conclusion.

Many difficult and troublesome musical questions are raised by such extensions of the serial concept. It is reasonable to question the sense in which dynamic differentiation, for example, can be usefully considered outside the context of a musical composition, and even within that context whether loudness can function as a variable, independent of timbre, texture, rhythm, tempo or register, to the same degree as pitch, pitch class or, possibly, rhythm. There also arises the larger question of the extent to which it is useful, or even meaningful, to consider whether a piece is serial without saying ‘how’ it is serial. When, for example, every pitch of a composition has been explained in terms of its position in some 12-note set, the problem remains of how this helps understanding of the conjunction of pitch, rhythm, dynamics, timbre and other elements of that piece. Even when all other dimensions have been derived in terms of unique predetermined orders, one may question that this necessarily shows how the result is heard, particularly when most musical dimensions are so highly contextual and subject to complex interaction. In short, the depth of musical relations within a composition may be so rich that the claim which that composition has to being a unique instance of musical thought may only in part be ascribed to the varieties of interrelations between serial aspects, and even the view of that part in these terms may be seriously questioned by the result which is the product of these interrelations. It may be more fruitful to consider serial ordering as a relatively abstract idea which has excited the imaginations of many composers and helped them to reshape and rethink their compositional habits and predilections in new and interesting ways. Perhaps the most important influence of Schoenberg’s method is not the 12-note idea in itself, but with it the individual concepts of permutation, inversional symmetry and complementation, invariance under transformation, aggregate construction, closed systems, properties of adjacency as compositional determinants, transformations of musical surfaces through predefined operations, and so on. Each of these ideas by itself, or in conjunction with many others, is emphasized with varying degrees of sharpness in the music of such different composers as Bartók, Stravinsky, Schoenberg, Berg, Webern and Varèse. In this sense the development of the serial idea may be viewed not as a radical break with the past, but as a particularly brilliant coordination of musical ideas which had developed in the course of recent history. The symmetrical divisions of the octave often found in Liszt and Wagner, for example, are not momentary aberrations in tonal music which led to its ultimate destruction, but, rather, important musical ideas which, in defying integration into a given concept of a musical language, challenged the boundaries of that language.

Twelve-note composition

BIBLIOGRAPHY

E. Stein: Neue Formprinzipien’, Arnold Schönberg zum fünfzigsten Geburtstage (Vienna, 1924), 286–303; Eng. trans. in E. Stein: Orpheus in New Guises (London, 1953), 57–77

F.H. Klein: Die Grenze der Halbtonwelt’, Die Musik, xvii (1924–5), 281–6

J.M. Hauer: Vom Melos zur Pauke (Vienna, 1925)

J.M. Hauer: Zwölftontechnik: die Lehre von den Tropen (Vienna, 1926)

K. Westphal: Schönbergs Weg zur Zwölfton-Musik’, Die Musik, xxi (1928–9), 491–9

R.S. Hill: Schoenberg’s Tone-Rows and the Tonal System of the Future’, MQ, xxii (1936), 14–37

G. Perle: Evolution of the Tone-Row: the Twelve-Tone Modal System’, MR, ii (1941), 273–87

A. Schoenberg: Composition with Twelve Tones’ (1941), Style and Idea (New York, 1950, 2/1975), 207–45

E. Krenek: New Developments in the Twelve-Tone Technique’, MR, iv (1943), 81–97

M. Babbitt: The Function of Set-Structure in the Twelve-Tone System (1946) (Princeton, NJ, 1992)

R. Leibowitz: Schoenberg et son école (Paris, 1947; Eng. trans., 1949); review by M. Babbitt, JAMS, iii (1950), 57

R. Leibowitz: Introduction à la musique de douze sons (Paris, 1949)

H. Jelinek: Anleitung zur Zwölftonkomposition (Vienna, 1952)

J. Rufer: Komposition mit zwölf Töne (Berlin, 1952; Eng. trans., 1954)

H. Pfrogner: Die Zwölfordnung der Töne (Zürich, 1953)

G. Perle: The Harmonic Problem in Twelve-Tone Music’, MR, xv (1954), 257–67

G. Perle: The Possible Chords in Twelve-Tone Music’, The Score, no.9 (1954), 54–8

M. Babbitt: Some Aspects of Twelve-Tone Composition’, The Score, no.12 (1955), 53–61

R. Gerhard: Developments in Twelve-Tone Technique’, The Score, no.17 (1956), 61–72

G. Ligeti: Pierre Boulez’, Die Reihe, iv (1958), 33–63; Eng. trans. in Die Reihe, iv (1960), 32–62

P. Stadlen: Serialism Reconsidered’, The Score, no.22 (1958), 12–27

R. Vlad: Storia della dodecafonia (Milan, 1958)

T.W. Adorno: Zur Vorgeschichte der Reihenkomposition’, Klangfiguren, Musikalische Schriften, (Berlin, 1959), 68–84

G. Perle: Theory and Practice in Twelve-Tone Music (Stadlen Reconsidered)’, The Score, no.25, (1959), 58–64

G. Rochberg: The Harmonic Tendency of the Hexachord’, JMT, iii (1959), 208–30

M. Babbitt: Twelve-Tone Invariants as Compositional Determinants’, MQ, xlvi (1960), 246–59; repr. in Problems of Modern Music, ed. P.H. Lang (New York, 1962), 108–21

E. Krenek: Extents and Limits of Serial Techniques’, MQ, xlvi (1960), 210–32; repr. in ibid., 72–94

R. Sessions: Problems and Issues Facing the Composer Today’, MQ, xlvi (1960), 159–71; repr. in ibid., 21–33

A. Webern: Der Weg zur neuen Musik (Vienna, 1960; Eng. trans., 1963)

M. Babbitt: Set Structure as a Compositional Determinant’, JMT, v (1961), 72–94; repr. in Perspectives on Contemporary Music Theory, ed. B. Boretz and E.T. Cone (Princeton, NJ, 1972), 129–47

D. Martino: The Source Set and its Aggregate Formations’, JMT, v (1961), 224–79

G. Perle: Serial Composition and Atonality (Berkeley, 1962, 6/1991)

M. Babbitt: Twelve-Tone Rhythmic Structure and the Electronic Medium’, PNM, i/1 (1962–3), 89–116; repr. in Perspectives on Contemporary Music Theory, ed. B. Boretz and E.T. Cone (Princeton, NJ, 1972), 148–79

D. Lewin: A Theory of Segmental Association in Twelve-Tone Music’, PNM, i/1 (1962–3), 89–116; repr. in ibid., 180–207

C. Lévi-Strauss: Le cru et le cuit, (Paris, 1964; Eng. trans., 1970)

S. Bauer-Mengelberg and M. Ferentz: On Eleven-Interval Twelve-Tone Rows’, PNM, iii/2 (1964–5), 93–103

H. Howe: Some Combinatorial Properties of Pitch-Structures’, PNM, iv/1 (1965–6), 45–61

P. Westergaard: Toward a Twelve-Tone Polyphony’, PNM, iv/2 (1965–6), 90–112

D. Lewin: On Certain Techniques of Re-Ordering in Serial Music’, JMT, x (1966), 276–87

M. Kassler: Toward a Theory that is the Twelve-Note Class System’, PNM, v/2 (1966–7), 1–80

L. Hiller and R. Fuller: Structure and Information in Webern’s Symphonie, Op.21’, JMT xi (1967), 60–115

J. Rothgeb: Some Ordering Relationships in the Twelve-Tone System’, JMT, xi, (1967), 176–97

E. Cone: Beyond Analysis’, PNM, vi/1 (1967–8), 33–51; repr. in Perspectives on Contemporary Music Theory, ed. B. Boretz and E.T. Cone (Princeton, NJ, 1972), 72–90

B. Boretz and E.T. Cone, eds.: Perspectives on Schoenberg and Stravinsky (Princeton, NJ, 1968, rev. 2/1972)

D. Jarman: Dr Schön’s Five-Strophe Aria: some Notes on Tonality and Pitch Association in Berg’s Lulu’, PNM, viii/2 (1969–70), 23–48

P. Batstone: Multiple Order Functions in Twelve-Tone Music’, PNM, x/2 (1971–2), 60–71; xi/1 (1972–3), 92–111

H. Pousseur: Stravinsky by Way of Webern: the Consistency of a Syntax’, PNM, x/2 (1971–2) 13–51; xi/1 (1972–3), 112–45

B. Boretz and E.T. Cone, eds.: Perspectives on Contemporary Music Theory (New York, 1972)

J. Maegaard: Studien zur Entwicklung des Dodekaphonen Satzes bei Arnold Schönberg (Copenhagen, 1972) [review in MQ, lxiii (1977), 273]

M. Babbitt: Since Schoenberg’, PNM, xii/1–2 (1973–4), 3–28

D. Beach: Segmental Invariance and the Twelve-Tone System’, JMT, xviii (1974), 364–89

R. Morris and D. Starr: The Structure of All-Interval Series’, JMT, xviii (1974), 364

D. Lewin: On Partial Ordering’, PNM, xiv/2 (1976), 252–7

D. Lewin: A Label Free Development for Twelve-Pitch-Class Systems’, JMT, xxi (1977), 29–48

R. Morris: On the Generation of Multiple Order Function Twelve-Tone Rows’, JMT, xxi (1977), 238–63

G. Perle: Berg’s Master Array of the Interval Cycles’, MQ, lxiii (1977), 1–30

D. Starr and R. Morris: A General Theory of Combinatoriality and the Aggregate’, PNM, xvi/1 (1977–8), 3–35; xvi/2 (1977–8) 50–84

G. Perle: Twelve-tone Tonality (Berkeley, 1978)

M. Hyde: Schoenberg’s Twelve-Tone Harmony: the Suite Opus 29 and the Compositional Sketches (Ann Arbor, 1982)

R. Morris: Set-Type Saturation among Twelve-Tone Rows’, PNM, xxii (1983–4), 187–217

S. Peles: Interpretations of Sets in Multiple Dimensions: Notes on the Second Movement of Arnold Schoenberg’s String Quartet 3’, PNM xxii (1983–4), 303–52

E. Haimo and P. Johnson: Isomorphic Partitioning and Schoenberg’s Fourth String Quartet’, JMT, xxviii (1984), 47–72

M. Stanfield: Some Exchange Operations in Twelve-Tone Theory’, PNM, xxiii/1 (1984–5), 258–77; xxiv/1 (1985–6) 72–95

M.L. Friedmann: A Methodology for the Discussion of Contour: its Application to Schoenberg’s Music’, JMT, xxix (1985), 223–48

M. Hyde: Musical Form and the Development of Schoenberg’s Twelve-Tone Method’, JMT, xxix (1985), 85–143

G. Perle ed.: The Operas of Alban Berg, ii: Lulu (Berkeley, 1985)

D. Headlam: The Derivation of Rows in Lulu’, PNM, xxiv/1 (1985–6), 198–233

A. Mead: Large-Scale Strategy in Arnold Schoenberg’s Twelve-Tone Music’, PNM, xxiv/1 (1985–6), 120–57

M. Babbitt: Stravinsky’s Verticals and Schoenberg’s Diagonals: a Twist of Fate’, Stravinsky Retrospectives, ed. E. Haimo and P. Johnson (Lincoln, NE, 1987), 15–35

C. Krumhansl, G. Sandell and D.C. Sergeant: The Perception of Tone Hierarchies and Mirror Forms in Twelve-Tone Serial Music’, Music Perception, v (1987), 31–78

R. Morris: Composition with Pitch Classes (New Haven, CT, 1987)

A. Mead: Some Implications of the Pitch Class/Order Number Isomorphism Inherent in the Twelve-Tone System’, PNM, xxvi/2 (1988), 96–163; xxvii/1 (1989), 180–233

R. Morris and B. Alegant: The Even Partitions in Twelve-Tone Music’, Music Theory Spectrum, x (1988), 74–101

M. Hyde: Twentieth-Century Analysis during the Past Decade: Achievements and New Directions’, Music Theory Spectrum, xi (1989), 35–9

A. Mead: The State of Research in Twelve-Tone and Atonal Theory’, Music Theory Spectrum, xi (1989), 40–48

A. Mead: Twelve-Tone Organizational Strategies: an Analytical Sampler’, Intégral, iii (1989), 93–169

E. Haimo: Schoenberg’s Serial Odyssey (Oxford, 1990)

R. Morris: Pitch-Class Complementation and its Generalizations’, JMT, xxxiv (1990), 175–245

G. Perle: The Listening Composer (Berkeley, 1990)

J. Straus: Introduction to Post-Tonal Theory (Englewood Cliffs, NJ, 1990)

R.B. Kurth: Mosaic Polyphony: Formal Balance, Imbalance, and Phrase Formation in the Prelude of Schoenberg’s Suite, op.25’, Music Theory Spectrum, xiv (1992), 188–208

A. Mead: Webern, Tradition, and Composing with Twelve Tones’, Music Theory Spectrum, xv (1993), 173–204

A. Mead: The Music of Milton Babbitt, (Princeton, NJ, 1994)

G. Perle: The Right Notes (Stuyvesant, NY, 1995)