Piano Concerto No. 18 (“Paradis”) in B-flat major, K. 456

By Wolfgang Amadeus Mozart

BORN : January 27, 1756 in Salzburg, Austria

DIED : December 5, 1791 in Vienna

Ω COMPOSED : 1784

Ω WORLD PREMIERE : Mozart recorded Piano Concerto No. 18 in his own catalog of works on September 30. The date of its first performance is unknown; the composer introduced it to Vienna on February 12, 1785.

Ω CLEVELAND ORCHESTRA PREMIERE : October 13, 1949, with George Szell conducting and Leonard Shure as soloist

Ω ORCHESTRATION : flute, 2 oboes, 2 bassoons, 2 horns, strings, and solo piano

Ω DURATION : 30 minutes

BY SEPTEMBER 1784 , Mozart had already composed four piano concertos that year, and two more were to follow.

On September 21, Mozart’s wife, Constanze, gave birth to their second child, Karl, and nine days later her husband completed his fifth piano concerto of the calendar year, this one in B-flat major. Mozart entered the new concerto in his own catalogue of completed works. It was eventually designated as No. 18 in the numbering of his music done long after the composer’s death.

The composer’s father Leopold almost certainly referred to this concerto in B-flat in a letter dated February 17, 1785, written to his daughter from Vienna, where he was visiting: “On Sunday evening… Madame Laschi gave a concert in the theater, at which… your brother played a glorious concerto which he had composed for Mlle Paradis for Paris. I was sitting only two boxes away and had the great pleasure of hearing so clearly all the interplay of the instruments that for sheer delight tears came into my eyes. When your brother left the platform the Emperor waved his hat and called out ‘Bravo, Mozart!’ And when he came on to play there was a great deal of applause.”

If only Leopold had obliged us by identifying the concerto by key, for it remains only an educated guess that the concerto he heard that evening was what we know as No. 18 and not one of the other five he composed in 1784. One clue from the manuscript of the concerto is that it includes cadenzas for the first and last movements. This points to the likelihood that the concerto was written for someone else — when Mozart played his concertos himself, he improvised cadenzas. Two previous concertos whose score include fully composed cadenzas (Nos. 14 and 17) were written for Barbara Ployer, a piano and composition student of Mozart’s. So, it seems logical that No. 18, with its fully composed cadenzas, was indeed written for “Mlle Paradis.”

Mademoiselle Maria Theresia von Paradis was celebrated in her time as a composer and virtuoso. That she was blind only added to her renown, as well as her connection to Empress Maria Theresa, to whom the family was close. But of her relations with Mozart we know very little.

Mlle Paradis’s concert in Paris, to which Leopold obliquely refers in his letter, took place earlier in 1784, before the concerto was completed. It is possible that she played it instead in London, where she appeared after Paris that autumn. It is equally possible that she never played it at all.

Irrespective of its official premiere, this concerto illustrates Mozart’s delight in wind instruments. The second subject of the first movement, for example, has a little chirpy tune on two oboes in thirds, to which a flute and a bassoon respond two octaves apart in a smooth line, as if to say “you have your kind of playing, we have ours.” Although the soloist later plays this theme, its true point has been made by the wind instruments.

The second movement is a remarkable set of variations, not on a simple tune but on a strained, melancholy melody in the minor key with expressive sighs and chromatic harmony. The tune sounds rather like a variation itself, especially in its second half. Furthermore, the variations each contain internal variations, so a generous counting could find 10 variations, not just five.

The first variation is given almost entirely to the piano, and the repeats are observed. The second has a statement by the orchestra, decorated by the piano. The third has a ferocious opening and a gentle response from the piano. The fourth turns to the major key, and the fifth involves both orchestra and soloist throughout. With its heartfelt close, this movement is one of the most elaborate and expressive in all the Mozart concertos.

The third-movement finale, in contrast, is a relatively simple rondo, with a sharp surprise in the middle when Mozart switches suddenly to B minor —  a jarring key to classical ears — and introduces 2/4 rhythms in the woodwinds in conflict with the prevailing 6/8 in the strings. This delicious effect looks far more complicated than it sounds, but resolves in a cheery conclusion, as Mozart well intended.

— Hugh Macdonald