The structure of concerto no.6 is a faithful recreation of the models that Viotti established. The heroic first movement Poco Allegro precedes the gentle second movement Adagio, in the sweet relative major. The third movement is an agile, martial Rondo Allegretto.
The piece was written for 1 flute, 2 oboes, 2 clarinets, 1 bassoon, 1 horn, and strings. As we can see, it is very similar to Viotti's Orchestra No. 22, which had an extra bassoon and timpani in addition.
Now, we arrive at the question: what did Libón mean by “ad libitum“ orchestral accompaniment? Did that mean that the wind parts only doubled the string, so they were redundant?
Quite the contrary: as will be seen in the analysis of the Concerto below, the wind parts are very prominent, especially in the opening Tutti, so I personally did not feel that the parts Libón provided served the purpose of doing a reduction at all.
In order to record a first preview of the Concerto - the first recording ever to be made of Libon's concerti - I tailored a reduction for string quartet, distributing the wind tunes to the available instruments to fill in the blanks. All this led me to conclude that this description was more of a commercial tactic of Libón, or maybe his publisher, to ensure that the work would be bought and performed.
The first movement's form is very close to the movement we analysed in the previous chapter for Viotti’s Concerto No.22. The first Tutti, which starts from afar, exposes the first theme using only the strings (cc.1-8). In the repetition of the first theme, the winds join in, adding more pathos to the first theme, and the military gestures appear to finalise the statement, (.cc. 9 - 24). The wind section takes over for the second cantabile theme (cc.25-41). The wind section takes over for the second cantabile theme (cc.25-41), leading into a spirited transition and final tutti section before the solo (cc. 42-59).
In the subsequent solo section (cc.60-116), the violin plays the themes previously exposed and reworked with a virtuoso flair. It is likely that these works showed all the charismatic tricks that Libon performed with great prowess, as he wrote them and they were tailor-made Overall, Libon had great agility in the left hand, rising to high positions in very fast gestures. Creative and irregular bow patterns and Cantabile sul g themes frequently appear, as expected.
After this first solo, we arrive squarely at the development, in its relative, F major. This form is also reminiscent of Viotti's Concerto, in which there are successive episodes of new material, rather than reworking with related thematic material. The tutti interrupts the solo with a lively fanfare (cc.117-131) for a few bars, to which the violin answers with a horn-like motive (cc.132-150).
Then, we return immediately to the re-exposition of the same solo theme of the beginning. Except for a few ornaments, it is essentially the same material, but the way he links themes A and B is surprising: here too, Libón writes detailedly a cadenza in the solo part (albeit within the framework of the barlines).
The recapitulated Theme B (188-203) now appears in D major. The rest of the virtuosic passages that finalise this movement (cc.204-215) appear to be very similar to the parallel place end of the exposition, if only with some differences in articulation and ornamentation. The closing Tutti (cc.216-221) is simple, consisting of a final phrase that reiterates the military gesture with the full artillery of the orchestra joining in.