Anyone who has ever taught knows the difficulties of preparing an exhaustive analysis of a work. If it is to be good, naturally it cannot be content with applied theory of form; the teacher may only dissect the composition in order to put it back together again later on, to recreate it – and that is the main task. He must quasi compose the piece anew before the pupil; for only if he sees how the entire piece is constructed from its component parts will he understand it; merely recognising those component parts is not enough. Interpretation and teaching meet on this high level – the teacher becomes the interpreter while the interpreter becomes the teacher (who requires anything else from him?). In this sense, then, Schönberg’s instrumentation is a brilliant analysis, written for large orchestra (like the preceding chorale arrangements), which magnificently succeeds in elucidating all aspects: harmony, counterpoint, form.
A precise phrasing, entirely in the Bachian sense, predominantly serves to interpret the melodic proceedings. However, no matter how equivocal the construction of a Bach theme may be, Schönberg phrases it in a different way almost every time. This is of course not arbitrary; it always depends on the theme’s formal stance, the instruments’ characteristics and the register. One example out of many: at the outset of the fugue’s third section, the subject first appears without any performance indications in the trombones, whereas the fourth and fifth notes of the answer (in the trumpet) are already joined by a slur and the three succeeding ones have staccato dots. This results in a disposition which resolutely emphasises the melody’s focus, indicating that the first three notes are to be understood as an anacrusis. In addition, this phrasing – retained in the subsequent nine-bar episode – reveals its thematic origin. The subject, entering anew in the horns, is still without indications, thereby creating a reference to the beginning, i.e. again the tonic form – again the same presentation. Now the answer returns in the clarinets and oboes with a different phrasing (more legato), adapted for the instruments’ character and the high register, yet simultaneously constituting a variation of the earlier performance indication.
Hans v. Redlich trenchantly remarks on the instrumental division as another way of elucidating melodic construction (cf. his essay Zu Schönbergs Instrumentierung zweier Bachscher Choralvorspiele in the March-April 1927 issue of Pult und Taktstock). It consists of dividing individual thematic components between two different instruments. Schönberg applies it often where Bach writes a melodic line as a single voice although, as a consequence of his eminent contrapuntal invention, it is basically, latently two voices.
Altogether, this score reveals every concealed relation. Long before the fugue subject enters, its preparation in the prelude is elucidated by appropriately placed accents and punctuating phrasing; and the orchestration reveals that the combination of the melodic turning points of two voices results in a third, the main theme which Bach virtually deliberately conceals.
The registrations of an organ form the sonic model for the instrumentation, which seeks to characterise some of the organ’s timbral properties – although here, in the orchestra, all that instrument’s awkwardness and shortcomings are stripped away and transformed into animacy, all limitations greatly extended. But no matter how rich, differentiated and forceful this score may be, there is not a single “effect” which is not expedient, meaningful and without musical justification. This is most outstandingly evident in the fugue, where the instrumentation precisely keeps pace with the thematical development, constantly enriching it. Applying every means available, from the well-known to the never before attempted, Schönberg achieves an overwhelming orchestral cumulation unrivaled in the entire literature.
Accentuating the fugue’s formal tripartition, the first section is played almost exclusively by the woodwinds (the subject set-up almost by the clarinets alone), the second initially by the strings only, and the third by the brass. The first part can be heard as an imitation of the organ’s sound. Retaining similar colours yields a simple sonic image which in no way detracts from the exposition. In contrast to the very usual way of dynamically highlighting a new entrance of the subject against the other voices (entirely contrary to the sense of absolute counterpoint as the full equality of all voices), distinct differentiation of the voices from one another is based only on carefully thought out phrasing. Simultaneities are dissimilarly articulated: legato vs. staccato, overlapping bowings. The effect of the last subject entry is heightened by introducing it in the tuba as the sole brass instrument.
For the second section, the strings take over the subject statement, before brass instruments join in. Initially in unison with the strings, supporting their phrasing and bringing out important points, they take over the subject later on, thus introducing instrumental differentiation as another intensifying level after the phrasing.
An ingenious emphasis indication, occurring twice, ushers in the third fugue subject, sounding in the brass. Now almost all the means described are applied together; tersest phrasing, keenest timbral differentiation, introduction of the subject in ever weightier, more forceful instrumental groups vie to build to a superb cumulation – and near the end, when all available means seem played out, Schönberg realises a tremendously bold idea. He doubles the subject, its power, not simplifying its loudness in the first three overtones, after organ practice, viz. in two forms, the one surpasses the other. At first, the octave, fifth and third progressions appear above the main voice only in the scale’s own pitches; then the doubling moves to the E-flat subject in B-flat and G. It is played by the celesta and the harp, moreover, which signifies the solution to a problem unsolved hitherto. Whereas these instruments were ineffectually lost in the tutti forte earlier on, here they influence the overall sound for the first time, despite their low volume. Indeed, they could have no other sonic character to fulfill this function – but in this way, the essence of their sound gains a characteristic feature of the overtones. That is, when they reinforce them, lifting the dimensionality of the fundamentals, their necessity – sounding without being heard, so to speak – becomes a virtue.
Felix Greissle, in Pult und Taktstock, Year VI 1929, vol. 4