Excerpt from CD booklet:

 

The first editions of the sonatas of Mozart, including those for violin and pianoforte, often bear the French indication, Sonates pour le Clavecin ou Forte-piano. This is usual still at the start of the following century, however it is often the case that the inclusion of both instruments in the title is for obvious commercial reasons only (it will occur even with the opus 13 of Beethoven); but indicative of the interchangeability between harpsichord and fortepiano, on the other hand, is the extremely frequent use at that time of the term Klavier, which indicates a generic designation for keyboard instrument. If, leaving the title aside, the “pianistic” intent of Mozart’s works appears clear in any case from a certain point onward, due to the type of notation and the dynamic indications, it is instead certain that for a good part of Mozart’s earliest sonata production performance on the harpsichord is not only perfectly pertinent and philological but, and above all, gives assuredly the right musical effect. And this fact is particularly true precisely for the sonatas for four hands; not so much because the original editions of these sonatas all carry the double indication (Clavecin ou Forte-piano), and even mature works like KV521 or KV 501 present the indication Cembalo primo e Cembalo secondo in the manuscript copies only, but above all for their intrinsic musical characteristics.

First of all, the harpsichord, with its clarity of attack and timbre, permits the rendering of those subtleties of musical articulation with clarity and enhances their importance, subtleties which are a central characteristic of the Mozartian style. It produces a musical result which is more transparent both for the polyphonic texture (such as is the case for the Baroque repertoire) and for those passages in which the totality of the many parts together, often forming chords, typical of the repertoire for four hands, risks producing a more confusing and heavy sonorous effect on the “Hammerklavier” (and especially on the modern pianoforte!), with struck strings, than on the quilled instrument, with plucked strings.

Furthermore, this repertoire, which aims to re-create sonorities which are more ‘symphonic’ with respect to the more intimate solo sonata (see for example, the frequent presence of unison passages typical of orchestral writing, and above all the solo-tutti dialectic), finds a perfect realization in the possible differentiation of sound and timbre levels thanks to the harpsichord’s two manuals; the two-manual instrument also facilitates greater emphasis on the ‘dialogue’ aspect of the writing in which a motive that is performed by one of the players is often imitated by the other in a different register and with a different sonority.

One of the most famous and important works of Mozartian iconography (the famous portrait by J. N. della Croce, here reproduced on the front cover, dated 1780-81 and kept at the Mozarteum) presents the complete family (including the deceased mother’s portrait which hangs on the wall), with the famous violinist father Leopold leaning against the keyboard instrument on which Wolfgang is performing a sonata for four hands together with his sister Nannerl; the position of the players’ hands on two levels clearly makes one think of a two-manual instrument and therefore of a harpsichord.  

 

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Mozart’s music still belongs to that type of music for which an execution based on a clear and intelligible “pronunciation” is indispensable for its comprehension and enjoyment. Musical execution was often compared in the Baroque era to the discourse of an orator; and such discourse had to be “clear and distinct” in order to transmit efficaciously to the listeners all the rhetorical effects which contributed to the ‘representation’ of the affetti and the resultant stirring of the affections which it was targeting.

Certainly, when playing Early Music instruments, the use of adequate articulation, which puts both metrical and expressive accents into relief, is indispensable in order to make up for these instruments’ limited possibilities for dynamic variation; but it is also true, however, that the Baroque aesthetic favours the particular, the chiselling of the details, the refinement of the decorations. Unlike the Romantic aesthetic (which instead favours a ‘global’ approach, with concentration given to the long line and the overarching form, to the breadth of phrasing and to large-scale dynamics, with a taste for a diffuse and amalgamated sonority, and therefore with minimal articulation and much use of legato between the individual notes), the Baroque aesthetic acquires its life, form and beauty from refined articulation and delicate dynamic shadings; all in all, it requires a fine brush rather than great and broad brushstrokes.

 

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                                                   Basilio Timpanaro   (English trans.: David Collyer)