What viola is?
The proportions of the viola cannot be as nearly defined as those of the violin, which can be said to have a standard size within quite small limits of variation. Fine violas exist, and are being played, whose measurements show variations of 1 1/2 to 2 inches in body length, and comparable differences in sounding string lengths. It seems that every imaginable combination of measurements has been tried in the as yet unfinished evolutionary process, the goal of which is to achieve an instrumental design that will answer to a common ideal of the viola's sound and capabilities. This common ideal is being delayed in its crystallizing by an unusual divergence of opinion among performers, composers, and listeners, both as to what kind of tone the viola should produce and what kind of music it should be expected to play. The viola presents an especially marked example of the continuity of the evolutionary process, which we cannot assume to be completed in the case of any of our instruments.
A hypothetical norm or average may be given for the principal measurements: length of body 16 5/8 inches; length of neck 6 1/16 inches; over-all length 27 1/4 inches; sounding length of strings 15 1/4 inches. Even the largest violas are not big enough in comparison with the violin to correspond to the pitch a perfect fifth lower, and this discrepancy is doubtless responsible in large part for the unique tone quality of the viola. The larger the instrument the more difficult it is to handle, especially when playing in upper positions.
The bow is somewhat thicker than the violin bow, and hence heavier.
The viola's heavier strings speak with more reluctance, and tone production requires a certain amount of "digging in." Light and airy types of bowing are therefore less natural to the viola than to the violin. They are not to be shunned, but one should realize that only skillful players with good instruments can make them sound effectively.
The two lower strings are wound with wire, the others being plain gut. Some players use wound strings for all four, and metal A-strings are also used.
The fingering system of the viola is identical with that of the violin. Since there is a difference of some 2 1/2 inches in the'two string lengths, the major and minor second intervals between the fingers are proportionately larger. Playing the viola requires a large hand and strong fingers, particularly the fourth finger, which is held in a more extended position than on the violin. The extension of the left forearm in the first position proves tiring after long playing. Positions above the third are inconvenienced by the awkwardness of getting around the shoulder of the viola with the left hand.
The harmonic obtainable by extension of the fourth finger in the seventh position is shown in the diagram, as it represents a practical upper limit for orchestral writing. Except as harmonics, notes higher than this are rarely written, and nearly always they are doubled by violins.
The normal clef for the viola is the alto clef (middle С on the third line). The treble clef (G clef) is employed when the part lies substantially above the range of the alto clef for a length of time. Too many clef changes should be avoided. A violist is quite accustomed to reading two or three leger lines above the staff, and he would prefer to do so rather than change clef for just a few notes.
Because of the wider spaces between fingers, the half position is more convenient on the viola than on the violin and is more frequently used.
Adjectives used to describe the tone of the viola, or of any other instrument, cannot do more than direct the student's attention to certain admittedly general and vague attributes. There is no way other than actual hearing to store up the memory impressions that make possible the mental hearing ability indispensable for the practice of the art of orchestration. One must develop the capacity to call to mind the sound of each instrument, comparing it to other instruments, but it is also important to distinguish differences in tone quality present in each single instrument.
The top string of the viola presents a striking contrast to the other three strings. Its timbre has been described as nasal, piercing, penetrating, and sandy. It has a tendency to sound unduly prominent, but it goes without saying that a good performer keeps a smooth balance in passing from the D-string to the A. The A-string's individuality is well exhibited in the following example.
The D-string is unobtrusive and gentle, although it has more tone- weight than the D of the violin. It is, with the G-string, the best part of the viola for the many kinds of accompaniment figure commonly allotted to it, and it is excellent for melodies like the following. Here the violas play in octaves with the oboe for two measures, and with the flute for the rest of the phrase.
While the G-string is subdued in comparison with the A- and C-strings, it gives a richer and warmer tone than the violin's G.
The C-string of the viola is the only one beyond the range of the violin. It is powerful and distinctive in timbre. Although coinciding with part of the range of the 'cello, its tones are in sharp contrast to the sound of the D-string of the 'cello. Those who look for subjective qualities find it foreboding and menacing. In the following example, with vigorous déraché bowing, in the lower half of the bow, it gives much solidity and energy to the string unison.The C-string is also capable of soft, delicate tones, as in this accompaniment figure for divided violas.
The situation of the viola in the middle of the pitch range of the strings seems to have made it the busiest member of the group. It is not only appropriate for melodies of its own, but it is constantly called upon to double violins at the octave or unison, or it may double the cellos or even the basses. The character and the sound of the viola are more suited to singing melody than to the performance of agile figuration.
It has always fallen to the viola to perform a great deal of harmonic filling up. Viola parts in scores of the classical period and later abound with passages in double notes, often without indication as to whether or not these are to be played divisi. The fact that they are nearly always practicable as double-stops, by good players, suggests that this may have been optional, but it is certain that the result is neater and the intonation more secure when the part is divided. Mozart considered violas entirely adequate and suitable for the important accompaniment at the beginning of the G Minor Symphony.
The absence of double notes in the viola part contributes to the transparency and fleetness of the orchestration of the Overture to The Magic Flute, whereas on the other hand the massive vibrancy of the Beethoven tutti is largely due to the violas three-part tremolo on the lower strings. Held chords for winds are omitted from the example.
When two notes lie both on the C-string, as in measure 2 of the next example, they must of course be played divisi.
In a modern orchestra there are usually twelve violas. In the period of Haydn, Mozart, and Beethoven, the number was at most five, with six to ten first violins and six to ten second violins. Violas have a heavier tone than violins, and in classical scores there is good evidence that the divided violas were thought a sufficient balance for the combined first and second violins.
The practice of dividing violas remains widespread to the present day, although one cannot say it is consistent enough to become the rule. There are many scores (e.g., Ravel's Daphnis et Chloé) in which the violas are given regularly two lines in the score. There are likewise scores in which divided violas are a rarity (e.g., Stravinsky's Symphony in C). It is now mandatory to mark clearly either div. or non div. when there are double notes.
VIOLAS AS BASS
A light bass situated in the octave below middle С is sometimes better given to violas than to cellos, in either arco or pizzicato.
DOUBLE-STOPS AND CHORDS
It is wise to adhere to the principle that the maximum stretch from first to fourth finger is the equivalent of a perfect fourth on one string,
for chords and double-stops in the lower positions. The payability of any combination can be judged by making diagrams similar to those advised for the violin. Three-part chords will be found more generally useful than four-part chords unless a fairly heavy effect is wanted, and open-spaced chords sound better than those in close position.
In the following example of a viola passage in a full tutti, the double- stops and chords are skillfully chosen to give the maximum sonority. Notice the large number of open string notes employed.
All harmonics are good, as on the violin. Artificial harmonics are seldom written above the third position D on the A-string.
Several notes above this D are perfectly playable as artificial harmonics, but there is little occasion for their assignment to violas rather than to violins. The lower-pitched harmonics of the viola are in a mors generally useful range.
For the glissando in harmonics, the longer string makes possible the extension of the natural series as far as the ninth partial. Notice the inclusion of the seventh harmonic in the following example.
It is noticeable between the various stringed instruments that the greater the string length the more resonant are the tones played pizzicato. The viola pizzicato is slightly rounder, less dry and short, than that of the violin in comparable register. High notes on the A-string tend to sound hard and wooden above E or F. This quality may be turned to advantage in appropriate musical circumstances. In the next example the viola doubles the first oboe at the unison, the first flute playing an octave above.
An example of extreme high pizzicato is found in Alban Berg's Violin Concerto, where it is employed in unison with harp, two flutes, and two clarinets. It is interesting to note that whereas these instruments are playing ff, the violas are marked f.
At another place in this work, Berg indicates pizzicato to be played over the fingerboard (Griffbrett) and then at the bridge (Steg). These differences in the manner of plucking the string have been little studied by composers, although used by players to obtain variations of tone quality. The score also contains the following example of left-hand pizzicato on the open C- and D-strings, while the bow plays on the G-string.
The tone quality of the viola lends itself especially well to the effect of bowing close to the bridge. The bow is frequently moved near to the bridge in the course of normal playing, in order to obtain more bite in the tone and a crisper rhythmic attack. This is doubtless the purpose of some uses of the indication sul poriticello. The mute is a practical obstacle to the proper position of the bow for a real ponticello effect.
The solo viola is not as frequently used in the orchestra as the solo violin, perhaps because its pitch and tone quality are such that it is easily covered by accompanying sounds. Nevertheless, there are many fine examples of successful writing for solo viola in symphonic scores. The very light accompaniment consists of a held D in the strings, the rhythm marked by staccato clarinets, harp, and two solo violins.
This striking passage for six solo violas occurs in Le Sacre du Printemps, accompanied by harmonics and pizzicato in cellos and basses. Division of the violas reaches its ultimate stage in the following example. Parts are written for six desks, all divisi, making twelve parts, or one for each player.