Mozart first heard the clarinet in London at the age of 8 when both he and the instrument were still musical novelties. As his skill and self-confidence as a composer matured, he used the clarinet increasingly in his orchestral works and operas, but he was reluctant about introducing it into his chamber music. While he was attracted by the instrument�s tone quality and unexcelled clarity in rapid passages, he apparently questioned its ability to blend in small instrumental groups.

The influence that eventually changed his mind was Anton Stadler, the first notable clarinet virtuoso in Vienna. Mozart and Stadler met in Salzburg in 1781, and their friendship ripened in Vienna where they were members of the same music circle and Masonic lodge. To Mozart, the relationship was not entirely rewarding � Stadler cheated the composer in money matters at a time when the latter was in financial straits, and for a while he lived like a parasite in Mozart�s home.

Their personal relations notwithstanding, Stadler helped Mozart realize the still untapped potential of the clarinet. Inspired by Stadler, Mozart wrote four great works involving or featuring the instrument � the Quintet for Piano and Winds, K. 452; the Trio for Clarinet, Viola and Piano, K. 498; the Clarinet Concerto, K. 622, and this quintet.

The quintet was completed on September 29, 1789, and was first performed on December 22, 1789, at a concert given by the Society of Musicians for the benefit of widows and orphans. Stadler, of course, played the clarinet, and Mozart, his favorite chamber music assignment, the viola.

What gives the quintet its unique place in chamber music is Mozart�s consummate skill in balancing the distinctive tone color and technical resources of the clarinet with those of the strings. While the clarinet cannot help but be conspicuous, it never protrudes like a solo instrument and never overshadows the first violin in agility or bravura. It alternates with the first violin in announcing themes and takes frequent rests to give the other instruments a chance. Mozart was particularly imaginative in using for special effect the chalumeau or lowest register of the clarinet with its rich, dark and throaty sound.

The first movement, in sonata form, is carefully constructed to establish and maintain a sound working relationship between the clarinet and its partners. Note, for example, the complementary roles played by the strings and the clarinet in presenting the first theme, the clarinet�s restatement of the graceful second theme against the gentle syncopation of the strings, and the subtle elaboration of this passage in the recapitulation. Note also the passage in the development in which rising and falling arpeggios in the clarinet shimmer above running 16ths that pass from one string instrument to another.

The slow movement is a romance: the strings put on mutes, and the clarinet sings a flowing aria-like melody. The minuet has two trios, the first in a minor key with the clarinet silent, and the second a dialogue in the style of a l�ndler (an Austrian country dance) between the clarinet and the first violin.

The finale is a theme and variations of such lucidity that it is frequently used as a classroom exercise in musical analysis. The theme is really a modified version of the motive that opened the first movement. Six variations follow, of which the third is in minor and the fifth is slowed to a poignant adagio. Listen for the plaintive little tune for the viola in the third variation; how violist Mozart must have thanked composer Mozart for that one!

Shostakovich composed this trio at the age of 17 while he was a piano student at the Moscow Conservatory. It is a short, one-movement work, reflecting the cautious melodic and harmonic language of the conservative faculty. The impertinent and rebellious Shostakovich of his First Symphony was still two years off.

At the time of the trio�s composition, young Dmitri was deeply in love with a fellow student, Tatiana Glivenko, the daughter of an eminent philosophy professor. Through personal contacts and correspondence, he continued to pursue Tatiana off and on for six years, losing interest only after she married another man and started to raise a family. Since he dedicated the trio to her, some romantically inclined commentators hear a love message in the work.

What�s the evidence? The opening measures present as a recurring motif two descending half-tones following one another. This motive launches the opening theme played by the violin and appears at the start of three follow-up themes in different rhythms and dress. For the first third of the trio, the descending half-tone motive is inescapable.

The motive then gives way to a romantic cello melody accompanied by tinkling variations and parallel triads in the piano. Here the half-tone motive is conspicuous by its absence.

Now, sequences of half-tones are traditional symbols in music of hopeless longing and yearning. (Wagner made abundance use of the pattern in Tristan and Isolde.) Thus, the trio opens, according to the music�s romantic interpreters, with Shostakovich expressing his longing for Tatyana. In contrast, the romantic cello melody without the half-tone pattern expresses his wished-for fulfillment.

Sure enough, after the opening material is restated, the trio concludes in celebratory fashion with a repeat of the fulfillment theme and a victorious C major chord. Comments one record jacket: Omnia vincit amor.

As a precocious teen-ager, Mendelssohn was interested in string sonorities � he composed his unique String Octet when he was only 16. As a brilliant pianist, he also took an early interest in the piano�s expanding resources, and it was inevitable that he turn to works combining piano with strings. During his lifetime, in fact, he wrote three piano quartets (piano plus three strings), a sextet (piano plus five strings), and two piano trios. The quartets and sextet were early works, however, and only the two trios, composed when he was 30 and 36, have entered the standard repertory.

Mendelssohn composed the second of his two piano trios in April, 1845, when he was at the peak of a hectic career as a composer, performer and music educator. He was the conductor of the Leipzig Gewandhaus orchestra, then as now one of Germany�s finest. In addition, he was the founding director of a new conservatory in Leipzig, and was in demand all over Germany as the guest conductor and pianist of his own music. Further, in the spring of 1844 had completed his eighth concert tour of England, conducting six concerts of the London Philharmonic in his own works and those of Bach and Beethoven.

Exhausted, in mid-July of 1844, he decided to take a year�s vacation at Soden, a resort near Frankfurt, where he could relax with his family except to meet a few long standing concert commitments. During this interlude, he composed his great Violin Concerto in September, this trio the following April, and his second String Quintet in July. In October he resumed his duties as director of the Gewandhaus, but on a reduced schedule of commitments, and his health and energy level continued to deteriorate until his untimely death in November, 1847.

In the trio�s first movement, Mendelssohn was particularly bold and resourceful in blending the sounds of the instruments. His basic building block is the arpeggio � a chord whose tones are heard in succession rather than simultaneously. Arpeggios are particularly effective on the piano when the damper pedal is used since the pedal permits the individual tones to accumulate.

The first theme, heard at the outset, consists initially of restless piano arpeggios, played pianissimo, with sustained notes in the cello and violin to establish an atmosphere of controlled tension. The tension is increased with a repetition of the arpeggio theme by the strings against piano chords. The music then breaks into a passionate strain for the violin and cello, against a 16th note accompaniment in the piano derived from the opening arpeggio figure.

The second theme is stated forte by the violin and cello, with the cello soaring into its upper register. While the melody is more lyrical, the piano continues the tension through another 16th-note arpeggio accompaniment. These elements are subjected to a long and dramatic development, with further exploration of the ubiquitous arpeggio pattern in the coda.

The second movement is more relaxed salon music in an undulating 9/8 rhythm. The main part of the ensuing scherzo, in fugal style and fast 2/4 time, is another of those excursions into fairyland that were a Mendelssohn speciality. However, a short contrasting middle section adds a Hungarian Gypsy flavor with trills, accented notes and fluctuations from major to minor.

The finale is again in sonata form, with a jogging first theme set off by the cello with an upward-leaping minor 9th and a buoyant second theme stated by all three instruments. But the real drama of the movement is deferred until the development when the piano introduces a chorale-like melody based on a Lutheran hymn Vor Deinem Thron. The climax of the entire work comes in the coda when the chorale is proclaimed fortissimo by all three instruments with almost orchestral sonority.

� 2006 by Willard J. Hertz