29 March 2009

Relational Semantics: Lutosławski’s Beauty of Indeterminacy, Surprise of Proportion

 Ariadne and Miri, Leitheim, 2001

A    fter 1961 Lutosławski worked largely independently of the fashions of the European avant-garde, refining and extending a compositional technique that produced, to use Bogusław Schäffer’s phrase, ‘stylistically the most independent works of modern European music’ ... Bohdan Pociej once described Lutosławski’s mature works in terms of four tendences: (1) the constant endeavour to achieve a ‘system’, to implement it, and to find one’s own personality [and social destiny] through it; (2) the harmonic, colouristic tendency—borne of a ‘Debussyan’ fascination with pure sound, grounded in a comprehensive [Cernerian] architecture of inter-related chords; (3) the poly-chronic tendency, reflected in a constant and intense inclination to organize ‘parallel plots’ and to split the composition into many interpenetrating levels and planes—to fill the musical space with multi-directional and multi-tiered motions; and (4) the dramatic tendency expressing itself in conflict, confrontation, struggle—in the various vicissitudes of form.”
  —  Steven Stucky, p. 107.
T he new recording of Lutosławski’s works for violin and piano, by Ariadne Daskalakis and Miri Yampolsky, has captured my imagination these past several days—and it may well capture yours as well.

  • Recitative e arioso (1951)
  • Partita (1984) [commissioned by Saint Paul Chamber Orchestra and premiered by Pinchas Zucherman and Marc Neikrug in January 1985 in Minnesota]
  • Subito (1992) [his final completed composition, before his death in 1994 at age 81; written for the International Violin Competition in Indianapolis]
T hese are pieces of tremendous clarity, alignment, and focus. They are, in fact, astonishing for a sort of post-traumatic stress disorder (PTSD) sort of ‘urgent, combative hyperclarity’.


    [50-sec clip, Daskalakis & Yampolsky, Lutosławksi, ‘Recitative e arioso’, 1.6MB MP3]


    [50-sec clip, Daskalakis & Yampolsky, Lutosławksi, ‘Partita’, 1.6MB MP3]


    [50-sec clip, Daskalakis & Yampolsky, Lutosławksi, ‘Subito’, 1.6MB MP3]

L utosławski destabilizes the chromaticism in the violin part characteristic. Opposing this, the piano has vertically symmetrical chords and seems to offer respite and restore stability. Lutosławski’s early love of mathematics and the aesthetics of symmetrical are evident here—when the distances between adjacent tones in the chords are measured, one gets a numerical pattern of pitches that is invertible ... the same whether measured from the top to bottom or bottom to top.

T he developments and the transitions are beautiful, and their beauty and coherence leads us to imagine that there can be success and a happy conclusion, if only we can be sufficiently mindful and ‘good enough’. But the best and most diligent efforts can be for nought, and our grip on success can slip away. Passages that initially sound complete and self-contained turn out to be erodable or transitory ... stuff happens.

T he violin part struggles existentially. Life and its accumulated burdens take their toll, and the violin ends up (in ‘Subito’) chromatically down a half-step from where it started.

T he motoric chromaticism of the violin and the contrast provided by the piano are beautifully rendered in the Subito and the Partita.

H ear these three pieces together, one after the other on this disc. You will be impressed by Lutosławski’s skill in constructing relational algebraic expressions (Verhaltniss). Which part is the operator and which is the operand? Is the violin-piano matrix singular? Is the operation that they just played ‘commutative’?

T he size and prominence of a part are context-dependent and comparative qualities—you form an impression of them only in relation to other parts, or to the overall whole. Size and prominence are indeterminate—indefinite qualities that empower the performer/listener. They can increase or diminish without limit; there is interpretive latitude—so much latitude, in fact, that it may lead to PTSD-like anxiety, agoraphobia.

O ur judgment about the relation of parts arises both from the evidence that’s provided in a particular piece (or performance) and from custom. These make us used to specific proportions, such that wide deviations from them strike us as novel or exaggerated or contradictory. If we hear something that’s common or familiar, our expectations are already pre-conditioned and we tend to hear what we are expecting to hear. But if we hear something that’s unusual, or if a familiar pattern or relationship has a part that is relatively larger or smaller proportioned than what’s customary, then it awakens ideas about uncertainty and disparity.

A nd it’s not just the scope or extent or prominence of a part where we are awakened by relational contrasts. There can be semantic misrelations as well. Paradoxically little stimulation evokes impressions of despair, depression. Unexpectedly abundant stimulation evokes impressions of mania, agitation. The Recitative e arioso is dark, dark, dark. The year 1951 must have afforded Lutoslawski lots of dark moments to propel this piece—and Daskalakis plays as though she understands this from the inside-out. The bowing technic admits alternately of great energy [“This is how I was mistreated, and here is what I did to oppose them.”] and then of great vulnerability [“At last there was nothing more we could do, and we had to wait and see what the outcome would be.”]. The consonance of performance and writing is wonderful, an embodiment of good relations between the semantics of the composer and the gestures of the performers—Daskalakis and Yampolsky alike.

T he so-called ‘poly-agogics’ that Lutosławski uses are tastefully handled. Polyagogics are simultaneous accelerandos in one part and slight ritardandos in the other part. These microrhythms amount to a kind of polymeter—a transient complexity that confers extra tension on the piece. The Subito and the Partita have poly-agogic features, often associated with veiled or pensive, waiting, uncertain passages. I will need to get a copy of the score, to see how many of the poly-agogic rhythms are notated ones and how many of them are extemporized by Daskalakis and Yampolsky. Either way, their skill and faithfulness to what Lutosławski meant are to be commended—a fantastic Naxos CD.

A riadne is the new Dean of Strings for the Hochschule für Musik Cologne. She is also leader of the Berlin-based Ensemble Oriol and of the Manon Quartet.

 Lutosławski 1993, photo (c) Freeman




22 March 2009

Is Salonen’s ‘Homunculus’ Quartet a Musical Hologram?

 optical holographic set-up, (c)2007 HowStuffWorks

D    oes Salonen go further to say anything about music and holography? You’ve got the snippet from Salonen’s program notes about wanting to write a compact miniature that implies and acts like much more. And you’ve got the link at the bottom of the post, to the Michael Talbot Universe-as-Hologram thing. But is there a Salonen interview where he actually talks about holograms? Does he think that ‘Homunculus’ could be divided up into smaller bits and each bit would still embody all of the characters and textures of the whole [like a cut-up hologram would do]?”
  —  Anonymous email commenting on the previous CMT post.
I    wanted to compose a piece that would be very compact in form and duration, but still contain many different characters and textures. In other words, a little piece that behaves like a big piece... I decided to call my piece ‘Homunculus’ despite the obvious weaknesses of the spermists’ thinking, as I find the idea of a perfect little man strangely moving.”
  —  Esa-Pekka Salonen, program notes.
T he blockquote above, which I transcribed from Esa-Pekka Salonen’s program notes, is all there is, unfortunately. I haven’t thought about it a lot (yet), but I do not think that this string quartet [its compositional structure; its acoustical properties when realized in performance] is holographic. If it is holographic, then it is a hologram of (a) ‘low resolution’ in the temporal domain and (Fourier-inverse) frequency domain and (b) represented in a nonlinear medium with ‘low quantization’ dynamic range. Just my impression.

W hich draws attention to the exoticness of holograms even now, sixty-some years after holograms were discovered/invented by Dennis Gabor. The usual notion of optical holograms is that the recording medium has linear contrast formation across a very wide range—6 or more binary bits of intensity quantization or more. And the usual notion of optical holograms—oh, cut off little a corner of the hologram and illuminate it and you still get the image of the whole thing.

B ut what’s seldom expressed—or what’s seldom conveyed in popular accounts for non-physicists, anyhow—is how the hologram image from the cut-off corner differs from the image from the whole intact hologram. Yes, the little cut-off corner is itself a hologram, from which you can cut off yet another corner and once again see the ‘same’ image of the original scene. But you can’t engage in decimation of the hologram down to a minuscule, invisible ‘corner’ of film that has only one atom, say. Or digital decimation of a file that was once many megabytes in size, down till what’s left is only one binary digit—one ‘bit’, a one or a zero.

N or is a [tiny but still visible/macroscopic] holographic ‘corner’ that is 1/1000th the size of the original—one milligram of film, out of an original hologram that weighs 1 gram—capable of showing the spatial detail or contrast that the full-size original did. Over-simplified, Future-obsessed DiscoveryChannel-ified ‘lay-audience’ excuses for ‘science journalism’ has no patience for these practical facts. Instead, we get breathless, sensationalized misinformation that backhandedly suggests that Miracles happen; that Fact is Stranger than Fiction; that infinite regressions of hologram snipping do not diminish the information contained by the progressively smaller snippets. It would be so much better if the journalists and marketers and popularizers were not running the show and if instead physicists and engineers wrote or edited the copy, for longer format shows that allowed time for a bit of real-world detail...

E   very part of a hologram contains the image of the whole object. You can cut off the corner of a hologram and see the entire image through it. For every viewing angle you see the image in a different perspective, as you would a real object. Each piece of a hologram contains a particular perspective of the image, but each also includes [or contains the representation of] the entire object.”
  —  R. Nave, Hyperphysics, Georgia State University.
S o when you cut up an optical hologram, the contrast and information corresponding to larger-scale structures does go down. Information is lost. The projected image from a tiny corner does broadly resemble the original, but its resolution is lower and other structure ‘signal’ information may now be so weak as to be overwhelmed by ‘noise’. Holograms have a ‘transfer function’ and signal-to-noise ratio (S/N), just like any other system. And those are not scale independent.

A nd the same thing would happen with holographic music, notwithstanding Brian Eno’s and others’ gee-whiz comments. I do not think Salonen’s ‘Homunculus’ is holographic, in part because I do not think it has ‘extra notes’ in it. By contrast, most ‘minimalist’ and ‘ambient’ music does contain extra, dispensable notes. I do not see how Salonen’s string quartet can be shortened without the omitted elements being conspicuous for their absence. There is no way that the ‘many characters and textures’ that Salonen put in there will be preserved if we cut the piece from 12 minutes down to, say, 6 minutes or 3 minutes or 1 minute. No way.

I t would be interesting, though, to examine ‘Homunculus’ through affine transformations of tempo, which would be analogous to optically scaling holograms with changes in wavelength (the inverse of frequencies corresponding to the colors of light). You could do this in live performance—doubling the tempo, say. Or you could do it by resampling a digital recording of it—accelerating the tempo by some multiplicative factor but leaving the pitches and timbres of the strings intact. Are the expressive consequences of affine transformations of tempo similar to the consequences of reanimating an optical hologram in blue light versus red light? Do the phrases appear shorter? At the faster tempi, are the phrases’ cognitive/emotional “reach” and the strength of interactions with each other more limited in scope, compared to how they are at slower tempi?

L ikewise, are ‘polarization’ effects observed in holographic music? That is, when wavefront-aligning (polarizing) constraints are imposed on two or more voices in a piece of chamber music, then are the interference patterns manifested by the other parts also polarized? In other words, has the composer established a polarizing ‘medium’ through which all of the ‘signals’ are propagating, and does the resulting acoustic ‘image’ behave in measurable ways that are analogous to an optical ‘polarization hologram’?

I f the answer is ‘Yes’ then maybe there are other holographic features in there, too. If the answer is ‘No’, then we can add that as evidence against holographicness of ‘Homunculus’.

I s any of Ferneyhough’s writing holographic, do you think? Can we tell what is a hologram and what is not by examining the ‘text’ (score), in a way that’s analogous to how we can tell whether the image on a piece of film is holographic? How would we go about composing a piece that we intend to be a musical hologram?

 Scaling of spatial dimension when hologram is exposed to light of different frequencies/wavelengths



It’s Notes All the Way Down: Salonen’s ‘Homunculus’ Quartet

 Johannes String Quartet, photo © Lisa-Marie Mazzucco

I    have long been fascinated (and amused) by the arcane Spermists’ theory, who held the belief that the sperm was in fact a ‘little man’ (in Latin, an ‘homunculus’) that was placed inside a woman to grow into a child. This seemed to them to neatly explain many of the mysteries of conception. It was later pointed out that if the sperm was indeed an homunculus—identical in all aspects but size to an adult—then the homunculus must have sperm of its own, [and, in turn, the homunculus’s sperm are themselves micro-homunculi with their own micro-sperm, which, in turn, are nano-homunculi, and so on]. This led to a logical ‘reductio ad absurdum’—an endless chain or infinite regress of [uncountable trillions of] homunculi within homunculi! This was not considered by [reality-challenged] Spermists to be a fatal objection, however—insofar as it neatly explained how it was that, in the biblical Adam, all [future human beings] had sinned: the whole of humanity [and its misdeeds] ‘was already contained in Adam’s loins’.”
  —  Esa-Pekka Salonen, 2008.
I    wanted to compose a piece that would be very compact in form and duration, but still contain many different characters and textures. In other words, a little piece that behaves like a big piece... I decided to call my piece ‘Homunculus’ despite the obvious weaknesses of the spermists’ thinking, as I find the idea of a perfect little man strangely moving.”
  —  Esa-Pekka Salonen.
T he performance by the Guarneri String Quartet and the Johannes String Quartet together last night in Kansas City was amazing. The program included:

  • William Bolcom: Octet
  • Esa-Pekka Salonen: Homunculus (Johannes Quartet)
  • Derek Bermel: Passing Through (Guarneri Quartet)
  • Felix Mendelssohn: Octet
T imothy McDonald has a nice review in the Kansas City Star here.

 Guarneri Quartet, photo © Dorothea von Haeften
T he Salonen ‘Homunculus’ quartet has many different expressions of parallelism and simultaneity in it—which is surprising, maybe, considering that the term ‘homunculus’ is ordinarily associated with concepts of hierarchy and encapsulation of things within things.

 Homunculus
T here are rapid sixteenth-note figures and sextuplets that come in waves—liquid waves, violins spilling, viola spilling, cello spilling. The patterns evoke a sense of ‘being-as-process’, as opposed to ‘being-as-object’.

F rom the title, one might expect that Salonen had been inspired by—or is exploring—individual subjectivity: the interior experience of an individual self and the self-regard that each of us has through introspection, mapping and remembering our own history.

B ut instead Salonen’s ‘Homunculus’ suggests that a quartet is (can be) one individual-in-aggregate, or, conversely, that a single individual is (can be) a collocation of multiple selves, each of whom has its own real existence and identity.

I t’s not so much what the self ‘is’ that interests Salonen, I think, but what the self does (hears, sees, thinks, anticipates, intends, ... ) and how it does it. It’s all ‘process’. Identity has no reality except as it is enacted through acts and processes and events. ‘Homunculus’ not only asserts (abstractly) that this is so; it also defends the argument by way of quartetly examples and illustrates the cognitive and emotional range of self-as-process. ‘Homunculus’ illustrates how rapidly selfhood can be constructed/revealed—with gestures and textures that unfold over a few seconds only. Salonen’s craftsmanship here is clear, but it’s never over-worked. Organic plausibility, palpable Truth.

S ome portions of the work have ‘sectional’ writing for three parts (Vn2, Vla, Vc, say) and the fourth part (Vn1, say) is essentially autonomous, doing its own thing. Several bars/seconds elapse, and the ‘section’ has been reconstituted by a different trio (Vn1, Vn2, Vc, say) and a different one (Vla) is doing the extemporizing. The effect is vividly evocative of the ebb and flow of our normal thought-patterns—the shifting of attention amongst a variety of ideas and ‘mental sets’.

W ithin the model ‘self’ is a concept embodied in a [measurably] finite number of critical sub-units of the overall system of ‘mental sets’ that are accessible to our ordinary experiences. If there is no involvement of one or more parts of this ‘self structure’, then we feel uninvolved; our internal ‘observer’ will be felt to be not present.

S ure, the self can be ‘divided’—have a look at Jon Elster’s and others’ writings about this. But because each self exists in a set of subsystems that are totally finite, the ‘division’ can’t go on indefinitely. After a couple of hierarchical levels, ‘self’ can’t be divided further without either losing the normal sense of the word ‘self’ or division’s becoming arbitrary, unsupported by evidence from ordinary experience. There is a philosophical/aesthetic reason why Salonen wrote this for quartet and not sextet or octet or something larger. In ‘Homunculus’ we get a pretty specific statement from Salonen about how finite each of us really is...

 Esa-Pekka Salonen
S o there are in fact some neuropsychological models that still characterize how our minds work in terms of homunculus-like mappings and correspondences, but the encapsulations are finite—there is no infinite regress or vast hierarchical matryoshka-type nesting.

I n fact, self watching self watching self … is implausible on its face. Every day we are amazed at our forgetfulness and limited attention. Have a listen to ‘Homunculus’ in concert if you have the opportunity to do so. I think you’ll find Salonen saying (abstractly, musically) that we are each complex selves, but we are not arbitrarily or infinitely complex. (Salonen convinces me, and I take comfort in his having succeeded in this.)

O    ne of the ‘complex’ things about ‘complex’ music is its quality of refusing to present a straightforward object (as for instance in much minimal sculpture): it is always perceived in the act of underlining its own ongoing and provisional nature. It doesn’t present the illusion of not being an illusion—in large measure because of the continual problematization of the performance/interpretaton context.”
  —  Brian Ferneyhough, Responses to a Questionnaire on ‘Complexity’, 1990.
T o fully explain how we experience what we do in this piece (or any other), a theory of consciousness would have to address real-time self-knowledge, self-understanding, self-awareness, self-monitoring, and goal setting: our selves as we know and understand and experience them; our selves as they are seen by others and used as a basis for their recognizing us as us; our selves as the sense of values and personal history and memory that constitutes our own recognition of who we are.

B ut, our minds (selves) do quite a lot of processing that’s ‘parallel’, not hierarchical or serial. We walk and chew gum at the same time; we contemplate and monitor several ideas at once; we process the concurrent expressions in this Salonen quartet and observe our own spontaneous reactions as we do this.

F or whatever forms and depths the ‘division’ of the self plausibly may have, though, the extent of the division is limited to the finite resources that in fact constitute ‘self’ within the system of mental sets that constitute our psyche. And those finite resources change on a moment-by-moment timescale. For example, the tutti and sectional structures in this 12-minute Salonen quartet do not place demands on us that are as great as the parts of the composition where the voices diverge from each other. As the processes unfold, the evolving cognitive demands—for the performers and for us listeners—are not excessive, and the musical result is coherent, pleasurable, beautiful.

T he narrative arc is compelling, and the effort of the collected selves apprehending this Salonen quartet is richly rewarded. I’ll have to get ahold of a copy of the score, to get a more detailed sense of how Salonen’s design accomplishes so much in such a short piece.

F our, five, six, eight voices at a time are about my own cognitive limit, however—which stands in stark contrast to the recent maniacal, parallel-not-hierarchical IVF exploits of Octo Mom to explore far higher cardinalities and polyphonies in one household.


 Matryoshka nesting dolls


20 March 2009

網絡空間: 個人空間的延展 Cyberspace: China, The Extension of Personal Space & Future of Everything

 Zhou Long

T    hinking about what we could do to share different cultures in our new society, I have been composing music seriously to achieve my goal of improving the understanding between peoples from various backgrounds. My conceptions have often come from ancient Chinese poetry. There are musical traits directly reminiscent of ancient China: sensitive melodies, expressive glissandi in various statements, and, in particular, a peculiarly Chinese undercurrent of tranquility and meditation. The cross-fertilization of color, material, and technique, and on a deeper level, cultural heritage, makes for challenging work. But there is more than this... more than reminiscence.”
  —  Zhou Long.
T he members of UMKC Wind Ensemble and Choir gave a nice performance last night at White Recital Hall (Steven Davis and Joseph Parisi conducting). The program included:

  • Chen Yi: Fanfare [premiere]
  • Zhou Long: The Future of Fire (for orchestra and choir; new transcription) [premiere]
  • Paul Rudy & Bobby Watson: Finally... (Bobby Watson, saxophone) [premiere]
  • James Mobberley: Words of Love (Rebecca Sherburn, soprano)
  • Alban Berg: Kammerkonzert (Benny Kim, violin; Robert Weirich, piano)
E ach work was admirably executed; and it was my intention to post some comments about the Berg piece, since, with 15 parts, it is the only one that’s totally consistent with the focus of CMT exclusively on ‘chamber music’. But limited time prevents me from putting up remarks about more than one piece right now, and ‘Future of Fire’ was the work that most captured my imagination.

P reviously, Zhou’s ‘Future of Fire’ was scored for orchestra and children’s choir—with the timbres and social implications that children singing to a predominantly adult audience can have. It has been performed, though, by adult choirs as well, including Chanticleer.


    [50-sec clip, Chanticleer, Zhou Long, ‘Words of the Sun’, 1.2MB MP3]


    [50-sec clip, Singapore Symphony Orchestra, Zhou Long, ‘Future of Fire’, 1.2MB MP3]

I n his new transcription, the orchestra is smaller, with textures that are more ‘chamber-like’. The 11 female voices were positioned on the left side of the stage, and the 7 men were on the right. The new transcription has the genders trading volleys—some of them lilting and lyrical, others punchy, punctate. There are no ‘extra’ notes, but there is an intense urgency ... a feeling of up-to-the-last-moment ‘indeterminacy’, about which notes the women’s parts will take next, and which notes will form the men’s parts’ response.

S o, ‘Notes Uncle’, which note? 五声阿叔, 孰徵? [wǔ-shēng-à-shú, shú-zhǐ?]

I  was reminded of the infamous YouTube video about ‘Bus Uncle’ [巴士阿叔, bā-shì-à-shú].

T he stream-of-consciousness mode that characterizes much of Zhou’s writing is present in ‘Future of Fire’, but now with a more assertive ‘mash-up’ quality and extemporaneity than it had in the children’s choir version. The volleys of disconnected gestures between the voices, the sound masses where vocal parts are doubled by instruments (women by woodwinds; men by brass)—these are clearly of Chinese origin and they are pure Zhou. But last night in the premiere of the new transcription, the atmospherics expressed (in Zhou’s abstract, modernist manner)... the future, not so much of Fire per se, but of Everything... The future of our world and our relationships with each other and with Authority.

F ire might, I think, be Zhou’s place-holder for ‘technology’ and our evolving array of social practices involving technology. In Web 2.0 social networking, what personal information may today be disclosed without the individual’s consent? 究竟在網絡這個「新世界」中,甚麼資訊是可以透露?

U nder what conditions or circumstances may it be disclosed? 在甚麼條件/情況下透露?

W hat musical expressions are strictly intimate, private, chamber-music-like, such that others have no right to mess with it or interfere with it? 又有甚麼資訊是嚴格屬於私人保有,別人無權干涉的呢?

T hese issues, to me, are what the new transcription of Zhou’s ‘Future of Fire’ assays. Truly wonderful, both in its beauty and in its political/social statement!

 Lucy Zhao, tr. of Walt Whitman ‘Leaves of Grass: Out of the Cradle, Endlessly Rocking’
I  , the singer of painful and joyous songs, the uniter
         of this life and the next,
Receiving all silent signs, using them all,
         but then, leaping across them at full speed,
Sing of the Past.

[Borne hither, ere all eludes me—hurriedly,
A man, yet by these tears a little boy again,
Throwing myself on the sand, confronting the waves—
I—chanter of pains and joys, uniter
         of here and hereafter,
Taking all hints to use them,
         but swiftly leaping beyond them,
A reminiscence sing.]”
  —  Lucy Zhao, tr. of Walt Whitman ‘Leaves of Grass: Out of the Cradle, Endlessly Rocking’; Peter Hessler, English back-translation from Zhao, in ‘Oracle Bones’, p. 458 ; [Whitman original].



15 March 2009

Tabula recompositoria: Amending/Improving Compositions Resembles Software ‘Refactoring’

W    hile composers were [in earlier Centuries] certainly able to work out music in their minds without recourse to writing, at some point the music had to assume a graphic form so that it could be preserved, transmitted, and performed. The evidence suggests that composers employed two different kinds of surfaces for writing down their music: (1) an ‘erasable tablet’ such as a slate that could be used many times and (2) paper. In the period [1450-1600 C.E.] we are considering, the pencil had not yet been invented, so writing on paper meant using pen and ink. Erasure could only be achieved by scraping the ink from the surface of the paper, often resulting in holes in the paper. Paper was therefore a ‘write-once’ medium. Despite the differences in the properties of the two kinds of writing surfaces, composers seem to have used them both in much the same way for all the written stages of a composition, from the earliest sketches to the final version.”
  —  Jessie Ann Owens, p. 74.
 Mozart K.581 Mvt.3 Trio II, mm. 1-12

    [20-sec clip, Umesh Shankar et al, UC Berkeley, 2003, Mozart, K. 581, Mvt. 3, ‘Trio II’, 0.4MB MP3]

M usical sourcecode (the musical score for a composition) is not sacrosanct: we honor the text in our reading of it, but we also take advantage of the interpretive latitude that it affords.

A nd any composer/arranger performs edits upon edits, to clean-up and perfect a work over a period of days to years. Or you create new versions to suit new and different purposes. It’s matter of what software developers would call ‘emergent design’.

Y ou may want to generate a piano reduction, exploding and imploding sectional structures, changing durations and meters, moving layers, manage instrument doublings, etc. .... Johnson’s book (link at bottom of the CMT post) has a good synopsis of these use-cases for MusicXML.

A lternatively, you may want to programmatically change your orchestration and timbres/sonorities, simplify or obfuscate/complexify the rhythms and horizontal relationships, de-risk the voice-leading to make it more natural to perform or sing, change the key to address the realities with regard to black-key biomechanics on keyboards or string-change biomechanics on stringed instruments. More and more use-cases for arrangers and composers!

S uzanne Clercx was the first to document the use of ‘erasable tablets’ by composers when in 1953 she published the discovery of a slate with six staves on each side [termed a ‘tabula compositoria’, ‘cartella’, ‘palierten schiffer stein’, ‘palimpsestus compositorius’, or ‘ardoyse’, depending on the country and century]. MusicXML is simply a latter-day tabula compositoria, that’s all.

W orking as I do on software in my day-job, I am impressed that compositions are homeomorphic to today’s object-oriented software and today’s data networks, including so-called ‘cloud’ computing or ‘software-as-a-service’ (‘SaaS’). All can be complex and difficult to manage.

I  suggest that the root of these problems lies in the complexity of the control and management planes—the orchestration and voice-leading and quasi-protocols coordinating the musical parts; the software and protocols coordinating the objects and network and distributed-services elements—and particularly the way the decision logic and the distributed-systems issues are inexorably intertwined.

I  am impressed that ‘refactoring’ the functionality can improve a composition just as it can improve a piece of software. There is no great profundity or earth-shattering novelty in such a view. It is just something that naturally occurs to any person who spends her/his days working on both software and music.

I  propose three key principles:

  • network-level objectives,
  • network-wide views, and
  • direct control
that I believe should underlie any [new/refactored] architecture, be it an object-oriented software system or a musical composition.

F ollowing these principles, I identify a design pattern that I call ‘4D’, after the architecture’s four planes: decision, dissemination, discovery, and data. A 4D architecture completely separates a network’s/composition’s decision logic from the compositional protocols and performance-practice/runtime protocols that govern the interactions among the network/musician elements.

I n creating a ‘4D’ design pattern, it’s important to remember that MusicXML score files do not represent ‘presentation-level’ primitives such as pages and staff-systems ... such details of formatting will change based on different paper and display sizes. But MusicXML does represent syntactic and semantic concepts of voices (parts) and synchronization among them, segmented into ‘movements’. In the MusicXML environment, in other words, formatting is handled separately from structure and semantics. The same applies for detailed interpretive performance information. Separate MusicXML supersets could be developed to represent individual printings and performances.

R efactoring of MusicXML can, of course, be done off-line—with generation of printed parts and score ahead of performance runtime. My MusicXML source for K.581 Mvt.3 Trio II is here. This (and several Beethoven string quartets) is what I have been testing my prototype MusicXML refactoring engine with this week.

O r the refactoring of MusicXML can be done in realtime—with refactored parts rendered with streaming MusicXML interpreter to be sight-read by the performers, with (I suppose) considerable surprise for artists who are deeply familiar with the original texts—and for listeners as well.

T he realtime MusicXML refactoring works okay so long as the lead-time for the canonical refactoring service is at least one measure ahead of where the musicians are playing. That, to me, seems to be about the minimum for proper scansion and so that phrasing and other effects are not too disrupted.

O f course, this depends on the meter and tempo and the prevailing complexity—things that are making cognitive demands on each performer. If a streaming realtime refactoring is too elaborate, then the aesthetics (and the fun) will undoubtedly suffer.

B eyond this, in principle I suppose one could mike each member of the ensemble and do analog-to-digital conversion of each signal—perform digital signal processing (DSP) and pattern-recognition to impute pitch and interval and rhythm and dynamics deviations from the score—and then use those imputed deviations to drive a refactoring server, to further permute the parts or effect meta-alteration of the downstream score. That’s beyond anything that I’m prepared to attempt right now, but CMT readers with enough studio gear and computational resources may be interested to try it.

    K. 581 Clarinet Quintet (‘Stadler’ Quintet) [1789]
  1. Allegro (A major)
  2. Larghetto (D major)
  3. Menuetto (A major), Trio I (A minor), Trio II (A major)
  4. Allegretto con variazioni (A major)
T he clarinet predominates in K.581 as ‘primus inter pares’ (‘first amongst equals’) as Alfred Einstein once wrote, yet the parts’ roles are more discursive and autonomous than they would be if this were a ‘concertante’ form where the soloist rules.

M y simple experiments initially have dwelt on Mozart’s K. 581, primarily because it is straightforward and familiar. Its interpretive history and performance practice are pretty transparent and well-understood. I wondered, “What if we refactored the Trio II, to render it as an exuberant/obstinate ‘recovery’ from the A-minor Trio I of the 3rd movement?” Okay. Here’s what I get with my canonical XML parser—scanning for and phrase and repeat boundaries in the tokenized MusicXML source.

 Mozart K.581 Mvt.3 Trio II, mm. 1-12
becomes  

 Mozart K.581 Mvt.3 Trio II, mm. 1-12
B asically, my “light” refactoring of K.581 treats every ‘repeat’ structure as a MusicXML ‘class’. You play it through the first time as originally written—that’s the first ‘invocation’ or programmatic ‘call’ to the ‘repeat’ class method with the contents of the bars between the repeat-delimiters as an argument. When you get to the end of the first time through, the method in the ‘main’ class (call it ‘A’) bumps an ‘excursion counter’ and calls the repeat class (call it ‘B’)—with a canonical refactoring argument to dynamically alter the articulation syntax in each part, according to rules I created for my refactoring engine to use.

 DSM Refactoring Engine Architecture
B ut the simple as-written MusicXML source then involves a ‘cycle’ between the ‘main’ class ‘A’ and the ‘repeat’ class ‘B’. If this were a software refactoring, generally we try to eradicate cycles, to localize and manage features and dependencies and to improve reliability and for other reasons. How about doing the same thing in MusicXML, with similar justification? Sure...

 DSM – removing cycles with dependency-inversion DIP
W hat my refactoring of the score does is this:
  • Extract a ‘repeat interface’ BI class from class B. BI contains the methods of class B that are needed by A, to implement the articulations (or other canonical changes that propagate through the quintet’s 5 parts) that we want to be associated with the repeats. The new, refactored class B implements BI.
  • Set all references in class A that aren’t required for object generation from B to BI.
A  simple ‘toy’ example, to be sure, but it is non-trivial—non-trivial in terms of the parser and its embedded logic, and non-trivial in terms of the expressive effects that this has.

I n the end, what we get in this example is a canonical cascading propagation of accents, tenutos, and decrescendos—explicitly amending the expressive sense of the K.581 Trio II. Cool. It works. And it suggests how we could implement other, fancier refactorings and canonical edits.

 Mozart K.581 Mvt.3 Trio II, mm. 1-12 repeat, after canonical XML mark-up with accents, tenutos, diminuendos
M y particular example refactoring of the MusicXML sourcecode for K.581 Trio II is directly analogous to what in the Roock-Lippert software refactoring book is called ‘dependency inversion’ or DIP (see. pp.130-43). Again, I was only exploring here what can be done with current-version MusicXML and refactoring techniques operating on music scores; I am not saying that anything wonderful has been done to K.581 with this attempt. I am only saying that it is interesting, and that it works, and that it may be of interest to you as a composer/arranger or as a music theorist. For CMT readers who are performing artists and avid users of PC-based digital music readers (like Hugh Sung or Nicholas Kitchen) maybe this stuff has interest as well.

T o me, the effort so far seems worthwhile. Yes, MusicXML is not ideal. It’s not a ‘causal encoding format’ and therefore and commands are [must be] used to encode single parts with multiple staves or multiple voices—and so on. While not ideal, MusicXML is the reigning standard that has market-share; it is the ‘bandwagon’ to jump on.

I t’s possible that these refactoring explorations will lead to new MusicXML enhancement-requests or new requirements-specifications for future versions of MusicXML. I’d welcome dialogue with you if you have observations or concerns in that regard. Please email me or comment here if you like. Thanks!

B    rian Foote suggested the name [‘speculative generality’] for a smell to which we are very sensitive. You get this smell when people say, ‘Oh, I think we need the ability to do this kind of thing someday’ and consequently specify all sorts of ‘hooks’ and special-case requirements—to handle things that aren’t in fact required. The result is often harder to understand and maintain. If all this machinery were being used, it would be worth it. But if it isn’t being used, it isn’t [worth it]. The extra machinery [to provide abstract generality] just gets in the way [of clean, effective, testable, maintainable source-code and non-defective solutions] ... Any structure or class that isn’t doing enough to pay for itself should be eliminated ...”
  —  Martin Fowler, p. 83.

A   ndrew Monk and others at University of York in the U.K. It is useful to think about software usability problems as forming a hierarchy with each successive level in the hierarchy requiring more contextualized knowledge. By contextualized knowledge we mean knowledge about a particular user and the goals and priorities which are relevant when the problems are identified. An example of a problem at the bottom of the hierarchy is a user having difficulty in correcting typographical errors because of inadequate delete facilities. This may be a quite general problem independent of the particular user and the task being performed. An example of a problem near the top of the hierarchy is the difficulty that a user might have in understanding how to carry out a database search task on some new system. The problem arises from the user's experience with the system, with other systems and with the task it is being used for and so depends very much on the context. Such problems often have a large impact on usability. By definition, these problems require information about the user's knowledge and beliefs in order to diagnose their cause, and to recommend the changes needed. Work at University of York has attempted to develop methods which elicit increasing amounts of context-sensitive data which can be used to diagnose problems at successively higher levels of this hierarchy and have identified four diagnostic levels. At the first level are problems that can be identified from system logs recorded from unknown users during free use. An approach was developed which identifies problems by isolating redundant user input. These problems can be diagnosed with minimal user-specific or task-specific information. A second level involved the analysis of log data from users completing tasks which have been set by the evaluator of the system. When these tasks are well constrained the system evaluator can use them to gain partial information about the users’ plans and goals when problems occur. This method is not always adequate since strategic differences amongst subjects can make plans and goals difficult to infer. A third level used verbal protocol methods to elicit users’ plans and goals directly. Two methods have been used re-enactment. Re-enactment proved particularly useful for diagnosing problems that could not be diagnosed from log data alone. In this method the user and evaluator discuss problems that the user had experienced during previous sessions.

Techniques that allow for more abstraction
  • Encapsulate Field - force code to access the field with getter and setter methods
  • Generalize Type - create more general types to allow for more code sharing
  • Replace type-checking code with State/Strategy
  • Replace conditional with polymorphism
Techniques for breaking code apart into more logical pieces
  • Extract Method, to turn part of a larger method into a new method. By breaking down code in smaller pieces, it is more easily understandable. This is also applicable to functions
  • Extract Class moves part of the code from an existing class into a new class
Techniques for improving names and location of code
  • Move Method or Move Field - move to a more appropriate Class or source file
  • Rename Method or Rename Field - changing the name into a new one that better reveals its purpose
  • Pull Up - in object-oriented programming (OOP), move to a superclass
  • Push Down - in OOP, move to a subclass
  • Shotgun surgery - in OOP, when a single change affects many classes—all affected code is kept in a single class, so that the change is made only in one place.”