Instrumentation. “Instrumentation” is the best term that can be found for that aspect of musical art which is concerned with timbre. The narrower term “orchestration” is applied to the instrumentation of orchestral music. Since the most obvious differences of timbre are in those of various instruments, the art which blends and contrasts timbre is most easily discussed as the treatment of instruments; but we must use this term with philosophic breadth and allow it to include voices. Instrumentation is in all standard text-books treated as a technical subject, from the point of view of practical students desirous of writing for the modern orchestra. And as there is no branch of art in which mechanical improvements, and the consequent change in the nature of technical difficulties, bear so directly upon the possibilities and methods of external effect, it follows that an exclusive preponderance of this view is not without serious disadvantage from the standpoint of general musical culture. There is probably no other branch of art in which orthodox tradition is so entirely divorced from the historical sense, and the history, when studied at all, so little illuminated by the permanent artistic significance of its subjects. When improvements in the structure of an instrument remove from the modern composer’s memory an entire category of limitations which in classical music determined the very character of the instrument, the temptation is easy to regard the improvement as a kind of access of wisdom, in comparison with which not only the older form of the instrument, but the part that it plays in classical music, is crude and archaic. But we should do better justice to improvements in an instrument if we really understood how far they give it, not merely new resources, but a new nature. And, moreover, those composers who have done most to realize this new nature (as Wagner has done for the brass instruments) have also retained, to an extent unsuspected by their imitators, the definite character which the instrument had in its earlier form.
As it is with mechanical improvements, so is it to a still greater degree with changes in the function of timbre in art. Throughout the 19th century so fatal was the hold obtained on the popular mind by the technical expert’s view of instrumentation, that it was impossible to hear the works of Handel and Bach without “additional accompaniments” conceived in terms of art as irrelevant to those of 18th-century polyphonys as the terms of Turnerian landscape are irrelevant to the decoration of the outside walls of a cathedral. There is some reason to hope that the day of these misconceptions is passed; although there is also some reason to fear that on other grounds the present era may be known to posterity as an era of instrumentation comparable, in its gorgeous chaos of experiment and its lack of consistent ideas of harmony and form, only to the monodic period at the beginning of the 17th century, in which no one had ears for anything but experiments in harmonic colour. We do not propose to concern ourselves here with those technical subjects which are the chief concern of standard treatises on instrumentation. Our task is simply to furnish the general reader with an account of the types of instrumentation prevalent at various musical periods, and their relation to other branches of the art.
The Vocal Style of the 16th Century.—In the 16th century instrumentation was, in its normal modern sense, non-existent; but in a special sense it was at an unsurpassable stage of perfection, namely, in the treatment of pure vocal harmony. In every mature period of art it will be found that, however much the technical rules may be collected in one special category, every artistic category has a perfect interaction with all the others; and this is nowhere more perfectly shown than when the art is in its simplest possible form of maturity. Practically every law of harmony in 16th-century music may be equally well regarded as a law of vocal effect. Discords must not be taken unprepared, because a singer can only find his note by a mental judgment, and in attacking a discord he has to find a note of which the harmonic meaning is at variance with that of other notes sung at the same time. Melody must not make more than one wide skip in the same direction, because by so doing it would cause an awkward change of vocal register. Two parts must not move in consecutive octaves or fifths, because by so doing they unaccountably reinforce each other by an amount by which they impoverish the rest of the harmony. Thus we justify, on grounds of instrumentation, laws usually known as laws of harmony and counterpoint. Apart from such considerations, 16th-century vocal harmony shows in the hands of its greatest masters an inexhaustible variety of refinements of vocal colour. A volume might be written on Orlando di Lasso’s art of so crossing the voices as to render possible successions of chords which, on a keyed instrument where such crossing cannot be expressed, would be a horrible series of consecutive fifths; the beauty of the device consisting in the extreme simplicity of the chords, combined with the novelty due to the fact that these chords cannot be produced by any ordinary means without incorrectness.
Decorative Instrumentation.—In the 17th century the use of instruments became a necessity; but there were at first no organized ideas for their treatment except those which were grounded on their use as supporting and imitating the voice. The early 17th-century attempts at their independent use and characterization are historically interesting, but artistically almost barbarous. Sometimes they achieve rare beauty by accident. Heinrich Schütz’s Lamentatio Davidi is written for a bass voice accompanied by four trombones and organ. The trombone parts are on exactly the same material as the voice, which in fact forms with them a five-part fugue-texture. The effect is magnificent, and admirably suited to the dignity of the trombone. Moreover, the opening theme is formed of slow arpeggios; and the more modern harmonic elements, though technically chromatic, consist, from the modern point of view, rather in swift changes between nearly related keys than in chromatic blurring of the main key. All this, especially in a writer like Schütz, who is saturated with every progressive tendency of the time, seems to point to a deep sense of the appropriate style of trombone writing. Yet, so insensible is Schütz to the euphony of his own work, that he proposes, as an alternative for the first and second trombones, two violins an octave higher, the other parts remaining unaltered! Imagination boggles at the vileness of this effect.
The chief work done in instrumentation in the 17th century is undoubtedly that of the Italian writers for the violin, who developed the technique of that instrument until it proved not only more resourceful but more artistically organized than that of the solo voice, which by the time of Handel had become little better than an acrobatic monstrosity. In the art of Bach and Handel, instrumentation, as distinguished from choral writing, has attained a definite artistic coherence. Choral writing itself has become different from what it was in the 16th century. The free use of discords and of wider intervals, together with the influence of the florid elements of solo-singing, enlarged the bounds of choral expression almost beyond recognition, while they crowded into very narrow quarters the subtleties of 16th-century music. These, however, by no means disappeared; and such devices as the crossing of parts in the second Kyrie of Bach’s B Minor Mass (bars 7, 8, 14, 15, 22, 23, 50) abundantly show that in the hands of the great masters artistic truths are not things which a change of date can make false.
But the treatment of instruments in Bach and Handel has a radical difference from that of the art which was soon to succeed it. It has precisely the same limitation as the treatment of form and emotion; it cannot change as the work proceeds. Its contrasts are like those of an architectural scheme, not those of a landscape or a drama. It admits of the loveliest combinations of timbre, and it can alternate them in considerable variety. Modern composers have often produced their most characteristic orchestral effects with fewer contrasting elements than Bach uses in his Trauer-Ode, in the pastoral symphony in his Christmas Oratorio, in the first chorus of the cantata Liebster Gott, wann werd’ ich sterben, and in many other cases; but the modern instrumental effects are as far outside Bach’s scope as a long passage of preparation on the dominant leading to the return of a first subject is beyond the scope of a gigue in a suite. Bach’s conception of the function of an instrument is that it holds a regular part in a polyphonic scheme; and his blending of tones is like the blending of colours in a purely decorative design.
Those instruments of which the tones and compass are most suitable for polyphonic melody are for the most part high in pitch; a circumstance which, in conjunction with the practice (initiated by the monodists and ratified by science and common sense) of reckoning chords upwards from the bass, leads to the conclusion that the instruments which hold the main threads in the design shall be supported where necessary by a simple harmonic filling-out on some keyed instrument capable of forming an unobtrusive background. The chords necessary in this part, which with its supporting bass is called the continuo, were indicated by figures; and the evanescent and delicate tones of the harpsichord lent themselves admirably to this purpose where solo voices and instruments were concerned. For the support of the chorus the more powerful organ was necessary. It is in the attempt to supply the place of this continuo (or figured bass) by definite orchestral parts that modern performances, until the most recent times, have shown so radical an incapacity to grasp the nature of 18th-century instrumentation. The whole point of this filling-out is that, the polyphonic design of the main instruments being complete in itself, there is no room for any such additional inner parts as can attract attention. In the interest of euphony some harmonious sound is needed to bridge the great gap which almost always exists between the bass and the upper instruments, but this filling out must be of the softest and most atmospheric kind. Bach himself is known to have executed it in a very polyphonic style, and this for the excellent reason that plain chords would have contrasted so strongly with the real instrumental parts that they could not fail to attract attention even in the softest tones of the harpsichord or the organ, while light polyphony in these tones would elude the ear and at the same time perfectly bridge over the gap in the harmony. There seems no good reason why in modern performances the pianoforte should not be used for the purpose; if only accompanists can be trained to acquire the necessary delicacy of touch, and can be made to understand that, if they cannot extemporize the necessary polyphony, and so have to play something definitely written for them, it is not a mass of interesting detail which they are to bring to the public ear. A lamentable instance of the prevalent confusion of thought on this point is shown by the vocal scores of the Bach cantatas corresponding to the edition of the Bach Gesellschaft (which must not be held responsible for them). In these Bach’s polyphonic designs are often obliterated beneath a mass of editorial counterpoint (even where Bach has carefully written the words “tasto solo,” i.e. “no filling out”). The same comments apply to the attempts sometimes made to fill out the bare places in 18th-century clavier music. There is no doubt that such filling out was often done on a second harpsichord with stops of a very light tone; but, if it cannot be done on the modern pianoforte in a touch so light as to avoid confusion between it and the notes actually written as essential to the design, it certainly ought not to be done at all. The greater richness of tone of the modern pianoforte is a better compensation for any bareness that may be imputed to pure two-part or three-part writing than a filling out which deprives the listener of the power to follow the essential lines of the music. The same holds good, though in a lesser degree, of the resources of the harpsichord in respect of octave-strings. To sacrifice phrasing, and distinctness in real part-writing, to a crude imitation of the richness produced mechanically on the harpsichord by drawing 4-ft. and 8-ft. registers, is artistically suicidal. The genius of the modern pianoforte is to produce richness by depth and variety of tone; and players who cannot find scope for such genius in the real part-writing of the 18th century will not get any nearer to the 18th-century spirit by sacrificing the essentials of its art to an attempt to imitate its mechanical resources by a modern tour de force.
Symphonic Instrumentation.—The difference between decorative and symphonic instrumentation is admirably shown by Gluck. In the famous dedicatory letter of his Alceste he mentions among other conceptions on which his reform of opera was to be based, that the co-operation of the instruments ought to be regulated in proportion to the interest and the passion, a doctrine of which the true significance lies in its connexion with other conditions of opera which are incompatible with the polyphonic treatment of instruments as threads in a decorative scheme. The date of this famous letter was 1767, but after Alceste Gluck was still able to use material from earlier work; and the overture to Armide is adapted from that of Telemacco, written in the year of Bach’s death (1750).
To write an account of symphonic instrumentation in any detail would be like attempting a history of emotional expression; and all that we can do here is to point out that the problem which was, so to speak, shelved by the polyphonic device of the continuo, was for a long time solved only by methods which, in any hands but those of the greatest masters, were very inartistic conventions. In the new art the concentration of attention upon form, as a more important source of dramatic interest and climax than texture, resulted in a neglect of polyphony which seriously damaged even Gluck’s work, and which always had the grave inconvenience that while the new methods of blending and contrasting instruments stimulated an increase in the variety, if not in the size of orchestras, there was at the same time extreme difficulty in finding occupation for the members of the lower middle class of the orchestra in ordinary passages. On the other hand, it is significant how everything in the development of new instruments seems to suggest, and be suggested by, the new methods of expression. The invention of the damper-pedal in the pianoforte epitomizes the difference between polyphony and symphonic art, for it is the earliest device by which sounds are produced and prolonged in a way contrary to the spirit of “real” part-writing. It is possible to conceive of any number of notes struck and sustained by the fingers as consisting of so many quasi-vocal parts; but when a series of single sounds is played and each sound continues to vibrate by means of a pedal which prevents the dampers from falling on the strings, then we are conscious that the sounds have been produced as from one part, and that they nevertheless combine to form a chord; and this is as remote from the spirit of polyphonic part-writing as modern English is from classical Greek.
The pianoforte trios of Haydn are perhaps the only works of first-rate artistic importance in which there is no doubt that the earlier stages of the new art do not admit of sufficient polyphony to give the instruments fair play. Haydn finds the pianoforte so completely capable of expressing his meaning that he is at a loss to find independent material for any accompanying instruments; and the violoncello in his trios has, except perhaps in four passages in the whole collection of thirty-three works, not a note to play that is not already in the bass of the pianoforte; while the melodies of the violin are, more often than not, doubled in the treble. Yet there is a certain difference between this and the work of a poor artist whose designs are threadbare. It would be impossible to add a note to Haydn’s trio; the only question is how to account for the superfluity of much of the string parts and how to make the trios effective in performance. It is sometimes suggested that the ’cello part is best omitted and these works played as violin sonatas. But experiment shows that in this condition much of the violin part sounds incomplete; and the truth appears to be that Haydn is thinking, like any modern composer, of the opposition of two solid bodies of tone—the pianoforte and the stringed instruments. And it will be found that the method of performance which most nearly justifies the instrumental effect of these otherwise beautiful works is that in which the pianoforte player regards himself as frequently doubling the stringed instruments, and not vice versa. He should therefore in all such passages play extremely lightly, so as to give the violin and ’cello the function of drawing the main outline. In the time of Bach such writing was beautifully suited to enliven the dry glitter of the harpsichord, and Bach’s duets for clavier and violin seem to have been sometimes played as trios with a violoncello playing from the clavier bass. But this was ineffective with the pianoforte, and is only explicable in Haydn as a survival. His trios were, indeed, published under the title of “pianoforte sonatas with accompaniment of violin and violoncello”; but this in no way militates against the above remarks as to their proper method of performance nowadays, when we take into consideration the greater strength of tone of the modern pianoforte, especially in the bass, and the fact that in no case could a violinist consent to play as an accompaniment such melodies as that at the beginning of the G major trio known as No. 1.
For Mozart there never was any such embarras de richesse in any combination of instruments. His music is highly polyphonic, and modern in its instrumental treatment throughout. It was lucky for the development of instrumentation (as in all branches of music during the change from polyphonic to formal design) that whenever the texture is not polyphonic the natural place for melody is on the surface: in other words, when the accompaniment is simple the tune is generally on the top. Haydn, when he was not tempted by the resources of an instrument so complete in itself as the pianoforte, soon learnt to write artistically perfect string quartets in which the first violin, though overwhelmingly the most important part, is nevertheless in perfect balance with the other members of the scheme, inasmuch as they contribute exactly what their pitch and the little polyphonic elaboration admissible by the style will enable them to give. In the treatment of the orchestra volumes might be written about Haydn’s and Mozart’s sense of fitness, as shown in Haydn’s experiments and Mozart’s settled methods. Where they consent to any practical custom from practical necessity they also consent because it is artistically right for them, and if it had not been artistically right they would have soon swept it away. For example, it has often been said that the extent to which their orchestral viola parts double the basses is due, partly to bad traditions of Italian opera, and partly to the fact that viola players were, more often than not, simply persons who had failed to play the violin. This was in many cases true, and it is equally true that Mozart and Haydn often had no scruple in following the customs of very bad composers. But, when we look at the many passages in which the violas double the basses, we shall do well to consider whether there is room in the harmonic scheme for the violas to do anything else, and whether the effect would not be thin without them. As music becomes more polyphonic the inner parts of the orchestra become more and more emancipated. Already Mozart divides his violas into two parts quite as often as he makes them play with the basses. In Beethoven’s orchestration there is almost always room for an independent viola part. There is not room for one together with an independent violoncello part; the wonderful use of muted solo violoncellos in the slow movement of the Pastoral Symphony being a special effect, like the earlier instance in Haydn’s 12th Salomon Symphony. Otherwise, when Beethoven has anything special for the violoncellos to say, he invariably softens and deepens their singularly incisive cantabile tones by doubling them with the violas. In the orchestras of his day this was perhaps the only safe proceeding for players unaccustomed to such responsibilities, and that may have been one of Beethoven’s reasons for it. But it is equally certain that the pure violoncello tone in large masses belongs to a distinctly different region of orchestral effect. Haydn’s numerous examples of independent violoncello melodies are almost all either marked solo or written for such small orchestras that they would be played as solos.
Similar principles apply in infinite detail to the treatment of wind instruments, and we must never lose sight of them in speculating as to the reasons why the genius of Beethoven was able to carry instrumentation into worlds of which Haydn and Mozart never dreamt, or why, having gone so far, it left anything unexplored. A subject so vast and so incapable of classification cannot be discussed here, but its aesthetic principles may be illustrated by the extreme case of the trumpets and horns, which in classical times had no scale except that of the natural harmonic series. This could be fixed, within certain limits, at whatever pitch suited the composition; but on the horn it could be only very partially filled out by notes of a muffled quality produced by inserting the hand into the bell of the instrument, a device impossible on the trumpet. These instruments thus produced, in Haydn’s and Beethoven’s times, a very remarkable but closely limited series of effects, which, as Sir George Macfarren pointed out in the article “Music” in the 9th edition of the Encyclopaedia Britannica, gave them a peculiar character and function in strongly asserting the main notes of the key. An instance of this characteristic function, specially remarkable because the composer has taken exceptional measures for it, is Beethoven’s overture to Fidelio. It is in E major, while Beethoven chooses to use trumpets in C. The only note which these can play in E major is the tonic, to which they are accordingly confined until the recapitulation of the second subject. This is unexpectedly placed in C major, the remotest key reached in the overture, and one that had already appeared in an impressive passage in the introduction which foreshadows the reference in the first act to the hero in his dungeon (“Der kaum mehr lebt und wie ein Schatten schwebt”). In this key the trumpets blaze out with an effect which entirely depends upon their restricted part hitherto. On a sufficient acquaintance with the work this would probably have revealed the essential nature of the instrument to a hearer unacquainted with technicalities, and revealed it rather as a characteristic than as a limitation. A still more remarkable instance will be found in the third statement of the theme of the finale of the 9th symphony. When the trumpets take it up they make a remarkable change at its 11th bar, for no other reason than that one of the notes, though perfectly within their scale, and, indeed, already produced by them in the very same bar, is so harmonized as to suggest the freedom of an instrument with a complete scale. This passage shows that if Beethoven had had the modern trumpet at his disposal, while he would no doubt freely have used its resources, he would nevertheless have maintained its character as an instrument founded on the natural scale, and would have agreed with Brahms that the nobility and purity of its tone depends upon its faithful adherence, at least within symphonic limits, to types of melody suggestive of that scale.
This brings us to the latest radical change effected in instrumentation, the change from symphonic to dramatic principles. It will be convenient to take one supreme composer as the artist who has dealt so consistently with the essentials of the new style that he may be conveniently regarded as its creator. Even with this limitation the subject is too vast for us to enter into details.
Dramatic Instrumentation.—There is hardly one of Wagner’s orchestral innovations which is not inseparably connected with his adaptation of music to the requirements of drama; and modern conductors, in treating Wagner’s orchestration, as the normal standard by which all previous and contemporary music must be judged, are doing their best to found a tradition which in another fifty years will be exploded as thoroughly as the tradition of symphonic additional accompaniments is now exploded in the performances of Bach and Handel. The main difference between symphonic and modern dramatic orchestration depends on this: that in a symphony any important incident will probably be heard again within five minutes, in every circumstance of formal symmetry and preparation that can attract the attention. This being so, it is absurd in a symphony to use only such orchestral colours as would be fit for dramatic moments which are not likely to recur for an hour or two, if they recur at all. Such a passage as bars 5 to 8 in the first movement of Beethoven’s 8th symphony is as unintelligible from the point of view of Wagnerian opera as the opening of the Rheingold is unintelligible from the point of view of symphony. But both are quite right. The modern Wagnerian conductor is apt to complain that Beethoven, in his four-bar phrase, drowns a melody which lies in the weakest register of the clarinet by a crowd of superfluous notes in oboes, horns and flutes. The complainer entirely overlooks the fact that this is the kind of music in which such a phrase will certainly be heard again before we have time to forget it; and as a matter of fact the strings promptly repeat it fortissimo in a position which nothing can overpower. A crowd of instruments that seemed at first to overwhelm it in sympathetic comments is perfectly dramatic and appropriate on the symphonic scale. On the operatic scale established by Wagner such detail is simply lost. Far greater polyphonic detail of another kind is no doubt possible, but it requires far longer time for its expression. It cannot change so rapidly. It engages the ear more exclusively, and therefore it needs an accuracy and an elaboration of paraphernalia quite irrelevant to symphonic art. The accuracy and the paraphernalia are equally exemplified in all Wagner’s additions and alterations of the classical orchestral scheme, for these all consist in completing the families of instruments so that each timbre can be presented pure in complete harmony. But the greatness of Wagner is shown in the fact that with all the effect his additions have in revolutionizing the resources of orchestration, he never regards his novelties as substitutes for the natural principles of instrumental effect. His brass instruments have lost nothing of their ancient nobility. In his gigantic designs it inevitably happens that instrumental resources are strained to their utmost, and there is, perhaps, hardly anything which the makers and players of instruments can be trained to do which is too remote to be demanded by some extreme dramatic necessity in Wagner’s scheme. But it is always some such extreme necessity that demands it, and never an appetite too jaded for natural resources. The crucial example of this is what Richard Strauss has ingeniously called the “al fresco” treatment of instruments in large orchestral masses (Berlioz-Strauss, Instrumentationslehre, edition Peters). Experience shows that in the modern orchestra there is safety in numbers, and that passages may with impunity be written for thirty-two violins which no single player can execute clearly. Whether this justifies Wagner’s successors and imitators in showing a constant preference for passages of which not even the general outline is practicable; whether it justifies a state of things in which the normal compass of every instrument in an advanced 20th-century score would appear to be about a fifth higher than any player of that instrument will admit; whether it proves that it is artistically desirable that when there are eight horns in the orchestra their material should be indistinguishable from pianoforte writing, and that, in short, the part of every instrument should look exactly like the part of every other—such questions are for posterity to decide. At present we can only be certain that the criterion according to which Brahms, being a symphonic writer, has no mastery of orchestration whatever, is not a criterion compatible with any sense of symphonic style. It is therefore not a criterion which can do justice to the principles of Wagner’s non-symphonic art, for its appreciation thereof is inevitably one-sided. Least of all can it conduce to the formation of sound critical standards for the new instrumentation which is now in process of development for the future forms of instrumental music. These, we cannot doubt, will be as profoundly influenced by Wagner as the sonata style was influenced by Gluck.
Finally it must be remembered that musical euphony and emotional effect are inseparable from considerations of harmony and polyphony. Timbre itself is, as Helmholtz shows, a kind of harmony felt but not heard. Not even the imagination and skill of Berlioz could galvanize into permanent artistic life an instrumentation based exclusively upon instruments, however suggestive his wonderful orchestral effects may have been to contemporary and later artists, who realize that artistic effects must proceed from artistic causes.
Chamber-music—The instrumentation of solo combinations is one of the largest and most detailed subjects in the art of music. Something has been said above as to its earlier aspects in the time of Haydn. Before that time it was based exclusively on the use of the harpsichord either as a means of supporting the other instruments or its also contributing principal parts to the combination. Thus there were no string-quartets before Haydn—at least none that can be distinguished from symphonies for string-band.
Richard Strauss, in his edition of Berlioz’s works on Instrumentation, paradoxically characterizes the classical orchestral style as that which was derived from chamber-music. Now it is true that in Haydn’s early days orchestras were small and generally private; and that the styles of orchestral and chamber-music were not distinct; but surely nothing is clearer than that the whole history of the rise of classical chamber-music lies in its rapid differentiation from the coarse-grained orchestral style with which it began. Orchestral wind-parts have been discovered belonging to Haydn’s string-quartet Op. 1, No. 5; his quartet in D minor, Op. 9, No. 4, is already in a style which not even the most casual listener could mistake for anything orchestral. On this differentiation of styles rests the whole aesthetics of chamber-music; but the subject is very subtle, and there is much, as for example in Schubert’s quartets and his C major quintet, that is inspired by orchestral ideas without in the least vitiating the chamber-music style; though, judged by its appearance on paper, it seems as unorthodox as the notoriously orchestral beginnings of Mendelssohn’s quartet in D and quintet in B♭. The beginning of Mendelssohn’s F minor quartet is, again, a case usually, but perhaps wrongly, condemned for its orchestral appearance on paper. Such matters cannot be decided off-hand by the mere fact that tremolos are characteristic of orchestras: the question is whether in individual cases they have not a special character when played by single players. Where this is so there need be no confusion of style; but the danger of such confusion is great, and with the rise of modern dramatic instrumentation it may be doubted whether there are any standards of criticism in current use for chamber-music of other than the sonata style. The development of pianoforte technique since Beethoven has been in some ways even more revolutionizing than that of the brass instruments; and pianoforte instrumentation, both in solo and in chamber-music, is a study for a lifetime.
Orchestral Schemes Typical of Different Periods.
1. 16th Century.—We, with our stereotyped modern notions of the grouping of voices, may get some idea of the freedom of the 16th-century composers’ imagination by noting that the four-part movements for semi-chorus or solo voices in Palestrina’s Masses present us with no fewer than seventeen different combinations of voices, and that of these the familiar group of soprano, alto, tenor and bass is not the most common, though it is invariable as that used for entire four-part Masses. In three-part movements Palestrina presents us with twelve combinations of voices. In his five-part Masses and single movements we find eight combinations, and his six-part Masses and single movements show eleven. And when he writes in eight parts for a double chorus the two groups are seldom identical.
2. 18th Century.—17th-century instrumentation may be neglected here as having begun in chaos and ended in the schemes of the 18th-century decorative instrumentation. The following is Bach’s fullest orchestra: the string-band, consisting (as at the present day) of violins in two parts, violas, violoncellos, doubled (where the contrary is not indicated) by double basses; the wind instruments (generally one to each part, as the string-band was never large)—2 flutes, 2 or 3 oboes, or oboe d’ amore (a lower-pitched and gentler type), taille or oboe da caccia (some kind of alto oboe corresponding to the cor anglais), bassoon, generally doubling the string basses, 2 horns, with parts needing much greater practice in high notes than is customary to-day, 3 (occasionally 4) trumpets, of which at least the first 2 were played by players especially trained to produce much higher notes than are compatible with the power to produce the lower notes (the high players were called Clarin-Bläser; and the others Principal-Bläser); a pair of kettle-drums, tuned to the tonic and dominant of the piece.
Handel’s orchestra is less detailed. He does not seem to have found any English trumpeters capable of playing as high parts as those of the German Clarin-Bläser, and his plan seems generally to get as many oboes and bassoons as could be procured to double the top and bottom of his string-band. But his definite orchestral effects in certain places (e.g. “He led them forth like sheep,” in Israel in Egypt, and the music of the Witch of Endor, and the appearance of Samuel’s spirit in Saul) are as modern as Gluck’s.
3. Symphonic Orchestration.—Mozart’s full symphonic scheme requires the string-band, 1 flute (rarely 2), 2 oboes, 2 clarinets (whenever he could obtain them, he being the first composer who really appreciated them, instead of regarding them either as cheap substitutes for the clarino or high trumpet of Bach, or, like Gluck and, with rare and late exceptions, Haydn, as merely adding to the force of tutti passages). Further, 2 horns, 2 bassoons, 2 trumpets and a pair of kettle-drums.
Mozart imports from church music 3 trombones for special passages in his operas.
Beethoven almost always has 2 flutes, and invariably 2 clarinets. In his 5th symphony he introduced 3 trombones and extended both the upper and lower extremes of the wind-band by a piccolo and a double bassoon. “Turkish music,” i.e. the big drum, cymbals and triangle, was used by Haydn in his Military Symphony, and Mozart in his Entführung, for reasons of “local colour”; it appears as an extreme means of climax in the finale of Beethoven’s 9th symphony.
4. Wagner’s Orchestra: Tristan und Isolde.—(Families of instruments are connected by a brace.)
Strings: as usual, but subject to minutely complex grouping.
3 flutes (3rd to play piccolo when required).
2 oboes.
1 cor anglais.
3 bassoons.
2 clarinets.
1 bass clarinet.
4 horns. (The mechanical improvements by which horns and trumpets acquired a complete scale have revolutionized the nature of those instruments; and Wagner’s orchestration, more than that of any other composer, has profited by this. Yet, in the preface to the score Wagner speaks very strongly of the loss of the original character of the horn in the hands of ordinary players; and goes so far as to say that, if experience had not shown that they could be trained to play nearly as smoothly as the classical players, he would have renounced all the advantages of the new mechanism.)
3 trumpets.
3 trombones.
1 tuba.
2 or, for safety in tuning, 3 kettle-drums.
Triangle and cymbals.
1 harp (multiplied quant. suf.).
In Der Ring des Nibelungen Wagner specifies the proportions of the string-band as 16 first and 16 second violins, 12 violas, 12 violoncellos, 8 double basses. The rest of the orchestra consists of—
Piccolo and 3 flutes.
3 oboes and cor anglais, or 4th oboe.
3 bassoons, or 2 and contra-fagotto.
3 clarinets and 1 bass clarinet.
8 horns, 4 of whom are also required to play 4 specially constructed tenor and bass tubas.
1 ordinary (double-bass) tuba.
3 trumpets.
1 bass trumpet. (A project of Wagner’s which instrument-makers found impracticable, so that Wagner had to content himself with a kind of valve trombone shaped like a trumpet.)
3 trombones and 1 double-bass trombone.
2 pairs of kettle-drums.
Triangle.
Cymbals.
Big drum.
Gong.
6 harps.
5. Chamber-music.—Bach’s and his contemporaries’ combinations with the harpsichord show the natural fondness, in his day, for instruments of a tone too gentle for prominent use in large rooms, or indeed for survival in modern times. Thus there was quite as much important solo music for the flute as for the violin; and almost more music for the viola da gamba than for the violoncello. A frequent combination was flute, violin and harpsichord (very probably with a violoncello doubling the bass), and in more than one case the violin was partly tuned lower to soften its tone.
Classical and modern chamber-music in the sonata style consists mainly of string-quartets for 2 violins, viola and violoncello; string-trios (rare, because very difficult to write sonorously); pianoforte-trios (pianoforte, violin and violoncello); pianoforte-quartets (pianoforte with string-trio); pianoforte-quintets (pianoforte with string-quartet); string-quintets (with 2 violas, very rarely with 2 violoncellos), and (in two important cases by Brahms) string-sextets. Larger combinations, being semi-orchestral, especially where the double-bass and wind instruments are used, lend themselves to a somewhat lighter style; thus Beethoven’s septet and Schubert’s octet are both in the nature of a very large serenade.
Wind instruments produce very special effects in chamber-music, and need an exceedingly adroit technique on the part of the composer. Magnificent examples are Mozart’s trio for pianoforte, clarinet and viola, his quintet for pianoforte, oboe, clarinet, horn and bassoon (imitated by Beethoven), his quintet for clarinet and strings, Brahms’s clarinet-quintet for the same combination, and his trio for pianoforte, violin and horn.