Gerd Zacher. Die Kunst einer Fuge. Johann Sebastian Bachs 'Contrapunctus I' in zehn Interpretationen.
The fifth interpretation is called 'Timbres-durées' and dedicated to Olivier Messiaen. One would assume it is reminiscent of Messiaen's electronic work by the same name; however, an explanatory note by Hauser (a written explanation by Hauser to a written explanation by Zacher to a musical 'explanation' by Zacher) suggests that this performance is at first based on a piano etude, 'Mode de valeurs et d'intensités', that was of great importance to Messiaen. (The composition forms the second part of the composition, Quatre études de rythme. 'Étude' can be understood in two different ways here. The term either refers to technical exercises for a pianist, or it pertains to Messiaen who contributed something entirely new to modern piano literature with this work.)
'Mode de valeurs et d’intensités' consists of three individual layers. (This is visible in the score by the use of three staffs.) Messiaen connects sound intensities to duration, the values of the notes. The predetermined relationship between the pitch and the tone duration remains unaltered throughout the course of the entire piece. (In dodecaphony, the order of notes is fixed by the series while its parameters are free. By contrast, the parameters pitch and duration of each note in 'Mode de valeurs et d'intensités' are fixed, but its order in relation to other notes is free. It may be regarded a prototype of a generalized serialism.) Thus, twelve pitch-tone duration pairs are established that continuously take turns on the three voices. 'There are three twelve-note groups or series, each consisting of all the notes of the chromatic scale. Each note is fixed in a register, so that the first group covers the upper range of the keyboard from top E flat down to B above middle C, the second group, the middle range from the G above this to the second A below middle C, and the third group, the middle to lower ranges from the second E flat above middle C to the lowest C sharp on the piano. There is, therefore, some considerable overlapping of the ranges, although no note occurs in more than one group in the same register. Each group is assigned a chromatic series of twelve durations - the first group, from one to twelve demisemiquavers, the second, from one to twelve semi quavers, and the third, from one to twelve quavers. These durations, in ascending order of value, are assigned to the notes of each group in descending order. The lowest notes on the piano, which have the greatest sustaining power, are therefore the longest and the highest are the shortest. As some durations are inevitably common to more than one group (the quaver, for instance, occurs in all three), there are a total of twenty-four different durations' (Johnson, p.105).
 Zacher adopts Messiaen's process of composing in a slightly modified way. 'Each note value is given its characteristic tone color: quavers and semi-quavers, the bright Cymbal, crotchets and minims fundamental Principal, all longer notes are garish in color (Krummhorn and Sesquialtera)'. Slightly modified. Unlike a pianist, a church organ player cannot control the volume. Therefore, Zacher changes the tone color. However, one could, of course, say that by changing the volume of a note on the piano, one also changes its tone color. That is why I speak of a slight modification.
Since Bach made less use of tone duration differences than Messiaen, the play between note values and tone color in 'Timbres-durées' is less sophisticated and refined than that of 'Mode de valeurs et d'intensités'. But the confrontation between two musical languages that were strictly separated before (intermusicality), the confrontation of Messiaen's working method with a text by Bach is without doubt very disturbing. The subject appears fragmented when the three quavers are suddenly assigned (played with) a totally different timbre than the preceding minims and crotchets. The course of each voice independently, which is of such importance in playing or listening with understanding to fugues, is completely distorted, even more so as the rhythmic variation increases. Seemingly uncontrolled and imperceptible to the ear, the voices tumble about themselves. 'Contrapunctus I' becomes spectral music, bringing timbre to the same level as melody, harmony, and form.
 'Timbres-durées' may be called a deconstruction in the most literal sense: destruction and construction at the same time. As does Derrida's deconstructive strategy, Zacher's interpretation also destabilizes the musical text from the inside. It works with and out of the vocabulary of the source text, but it transgresses the order of conventional interpretation. Bach's text becomes divided against itself, dislocated. Yet, it is important to point out that this interpretation (Derrida would call it an act of violence) is not directed against Bach. It would not be possible if the musical text were 'not of itself unbound and hence open to the wholly other, to its own beyond, in such a way that it is less a matter of exceeding that language than of treating it otherwise with its own possibilities' (At This Very Moment, p.17). Bach's work is possessed of a dehiscence; through Zacher's reading the work bursts open and goes unto the other. Performing the ethical (cf. Music, Deconstruction, and Ethics). 'Timbres-durées' is a destruction of 'Contrapunctus I'. But Zacher also emphasizes its constructive nature. 'As the eye sees an overall form even in a picture made up entirely of dots, here the points of time together form the original model of the fugue'. It is a new, albeit a temporary, construct based on the 'original' text.
 According to Zacher, 'Timbres-durées' may be called a spectral analysis of the fugue. A spectral analysis. Analysis of a spectrum in order to acquire qualitative and/or quantitative data about the medium from which the spectrum originates. In astronomy, a spectral analysis provides insight into the composition and structure of celestial bodies. The same holds for a spectral analysis of white light. Separated by a prism, white light falls apart into its 'component colors'. 'Timbres-durées' may be understood similarly. Zacher's spectral analysis of the duration structure reveals the rhythmic structure and construction of the fugue. Regarded as such, one could speak of a 'decomposition' of the fugue - it falls into its rhythmical components. 'The entire texture is analyzed in the minutest detail, so that the element of time seems to be dissected'. Decomposition. 'Contrapunctus I' breaks out of the unity proposed by Bach. The web is unraveled; a structural element (rhythm) is exposed. However, the object is not to explore (for the sake of theoretical curiosity), nor to restore (with an eye on future reconstruction), nor to destroy (the destruction of the source text). 'Timbres-durées' is transformative (transfigurative). Zacher examines the possibility of a different interpretation. (Can it still be called an interpretation?) The decomposition brings the openness of Bach's text to our attention, the possibilities of deformation, innovation, and active transformation. Although this transforming and reforming is not the same as destroying, it cannot be done without a certain degree of violence. Its nature, however, is clearly affirmative. It stands open to the other, to what a conventional analysis would (has to) ignore (cf. Deconstruction - an Affirmative Strategy of Transformation) .
 A spectral analysis. An analysis of music usually involves words. 'Timbres-durées', however, is not a traditional musicological analysis; rather, it is an audible analysis, an analysis in musical terms, an operative analysis at a church organ. It is a decomposition, a deconstruction of music in and by music. With 'Timbres-durées', Zacher not only escapes the conventional performance praxis, but also rises above the common musicological interpretations. In doing so, he inaugurates a different kind of analysis, an outlook on 'Contrapunctus I' that is based on its rhythmical units. ('The different rates of momentum are clearly evident'.) His analysis, however, is totally different than that of Dahlhaus (cf. Contrapunctus I) . By considering the rhythmical figures as motives, Dahlhaus points out the relationship of the individual voices which brings the unity of 'Contrapunctus I' to light. By contrast, the unity in Zacher's rhythmical analysis is disrupted, the voices disintegrate, the mutual relations become diffuse and opaque. Precisely by suspending conventional notions of unity and thematic coherence, he is able to expose aspects of the fugue that are inherent in it, but that, as of yet, have gone unnoticed.
Hence, 'Timbres-durées' may also be called a spectral analysis, spectral music, in a different sense. It is spectral in the sense of being ghostly. The fifth interpretation is spooky, eerie; it is a spectral apparition. To reveal this, Zacher needs to abandon a scholarly reconstruction or interpretation according to dominant conventions. That is the only way he is able to perform this analysis. 'There has never been a scholar who really, and as scholar, deals with ghosts. A traditional scholar does not believe in ghosts', says Derrida (Specters, p.11). To paraphrase the imperative that follows: it will always be a mistake not to read and reread Bach and to go beyond scholarly reading. It will be more and more of a mistake, a failure of theoretical and music(ologic)al responsibility (cf. Specters, p.13). Scholars are not always in the most competent position to be open to spectral analysis. They will perceive 'Timbres-durées' as strange, alien, perhaps even frightening. (Zacher would rather describe Die Kunst einer Fuge with such phrases as 'make friends with', 'acquaintance', and 'to become fond of'. It is precisely through selective listening that music is violated. Zacher's spectrum of the ten interpretations disallow the listener to shut his ears for the unexpected aspects of this music.) With 'Timbres-durées', Zacher surpasses ordinary scholarship. He takes responsibility. He takes it in music. By offering hospitality to the other(s). Through/in/by music, the other in music, an other music. By paying honor to the heterogeneity of Bach's text. (His 'outside' already resides within Bach's music.) Through a very accurate handling of the musical notation, he brings elements to light that remain concealed in a conventional scholarly reading of the score. The more accurate he (re)(de)constructs, the closer he gets to the imponderable.
'Timbres-durées'. Deconstruction in music. Referring to deconstruction, Derrida says: 'The issue, then, in undertaking, practically and theoretically, these new modes of articulation, is to fracture a still quite hermetic closure' (Positions, p.83-4).