Another important factor in the expressive rendition of music is dynamics, i.e., the relative loudness and softness of tone. The composer is supposed to have a fairly large share in this phase of expression, and in modern music always indicates in the score at least the most important dynamic changes that he has in mind. But our observation of musical performances tends to make us feel that in this aspect, even more than in tempo changes, it is the conductor or performer who must bear the greater responsibility, and that the amount of dynamic contrast to be employed certainly depends entirely upon the taste of the conductor or performer.

It is safe to say that the dynamic factor is easier to control than is the tempo, and yet in spite of this fact, there is no question but that the rendition of most choral and orchestral music could be made much more interesting if it could be given with a greater variety of dynamic shading. Nor is there, in our opinion, any question but that the changes from forte to piano and vice versa, the gradually worked up crescendos, the vigorous accents on certain important tones or chords, together with those subtler shadings often referred to as dynamic nuances, may become just as important and powerful a means of conveying emotional effects as tempo. Joy and triumph and exuberance are of course expressed by forte and fortissimo effects (the crowd at a football game does not whisper its approval when its own team has made a touch-down), but the image of a mother singing a lullaby would demand altogether different dynamic treatment.

The crescendo is one of the most powerful means of expression that the composer has at his disposal—especially in writing for the modern orchestra, but there seems to be a good deal of misunderstanding on the part of amateur conductors and performers about the real meaning of the term. Crescendo does not mean forte; indeed Weingartner (op. cit., p. 6) quotes von BÜlow as remarking that crescendo signifies piano,—meaning of course that a crescendo usually implies a soft beginning.

It should perhaps be noted at this point that there are two varieties of crescendo; one being produced by performing succeeding tones each more loudly than the one immediately preceding it; the other by prolonging the same tone and increasing its power gradually as it continues to sound. The first type is much commoner than the second, and is indeed the one kind of crescendo that is possible in piano playing; but the second variety can be secured in the case of an organ with swell box, the human voice, and in both string and wind orchestral instruments. Since some of the most beautiful musical effects may be produced by the use of this second type of crescendo, it should be employed very much more than it is in choral and orchestral music. The English conductor Coward takes the ground that the swell (a combination of crescendo and diminuendo) is the most powerful choral effect in existence.[17]

When the composer wishes to build up a really tremendous climax and sweep all before him by the intensity of the emotional excitement generated, he frequently indicates an increase in the amount of tone, coupled with a very gradual acceleration in tempo, all proceeding by slow degrees, and perhaps accompanied by a rise from a low pitch register to higher ones. If on the other hand, he wants to let down in emotional intensity, he does the opposite of all these things. The combination of crescendo and ritardando is also tremendously effective.

In order to bring together in fairly comprehensive array the terms that are ordinarily used by the composer to indicate various expressional effects, a table of the most frequently encountered dynamic expressions is here included.

We shall close our discussion of the subject of dynamics with a brief presentation of a few practical matters with which every amateur conductor should be familiar.

The pianissimo of choruses and orchestras is seldom soft enough. The extreme limit of soft tone is very effective in both choral and orchestral music, and most conductors seem to have no adequate notion of how soft the tone may be made in such passages. This is especially true of chorus music in the church service; and even the gospel singer Sankey is said to have found that the softest rather than the loudest singing was spiritually the most impressive.[18]

Pianissimo singing or playing does not imply a slower tempo, and in working with very soft passages the conductor must be constantly on guard lest the performers begin to "drag." If the same virile and spirited response is insisted upon in such places as is demanded in ordinary passages, the effect will be greatly improved, and the singing moreover will not be nearly so likely to fall from the pitch.

The most important voice from the standpoint of melody must in some way be made to stand out above the other parts. This may be done in two ways:

The second method is frequently the better of the two, and should more frequently be made use of in ensemble music than is now the case in amateur performance.

The conductor of the Russian Symphony Orchestra, Modeste Altschuler, remarks on this point:

In polyphonic music containing imitative passages, the part having the subject must be louder than the rest, especially at its first entrance. This is of course merely a corollary of the general proposition explained under number three, above.

In vocal music the accent and crescendo marks provided by the composer are often intended merely to indicate the proper pronunciation of some part of the text. Often, too, they assist in the declamation of the text by indicating the climax of the phrase, i.e., the point of greatest emphasis.

The dynamic directions provided by the composer are intended to indicate only the broader and more obvious effects, and it will be necessary for the performer to introduce many changes not indicated in the score. Professor Edward Dickinson, in referring to this matter in connection with piano playing, remarks:[19]

In concluding our discussion of dynamics, let us emphasize again the fact that all expression signs are relative, never absolute, and that piano, crescendo, sforzando, et cetera, are not intended to convey to the performer any definite degree of power. It is because of misunderstanding with regard to this point that dynamic effects are so frequently overdone by amateurs, both conductors and performers seeming to imagine that every time the word crescendo occurs the performers are to bow or blow or sing at the very top of their power; and that sforzando means a violent accent approaching the effect of a blast of dynamite, whether occurring in the midst of a vigorous, spirited movement, or in a tender lullaby. Berlioz, in the treatise on conducting appended to his monumental work on Orchestration, says:[20]