The "usual" modulation scheme of the Baroque period is also often found in Scarlatti's work, it is about the half-closing-full closing principle. The half-ending is on the dominant and the full ending on the tonic. Scarlatti, however, would not be Scarlatti if there were not numerous exceptions in this field too, which are very idiosyncratic and certainly extremely unusual for the time. These are harmonic structures that are unique in their appearance even in later epochs of music history. All of the exceptions discussed below are dictated by musical logic, which for Scarlatti was significantly more important than the strict rules of music theory, in which he apparently never really believed. He was probably the first to believe that bans can only limit creative freedom. Through his work, he has often harshly challenged music theory. Here, too, there is the reference to the modality, which could unfold in complete freedom. Scarlatti also made use of this right for himself and consistently enforced it. Some of his innovations in this area have never been repeated after him. This is indicative of his courage and his unconventional attitude, which, however, is essentially more conventional than that of all his contemporaries, since it is based on principles of modality. One can wonder whether Scarlatti's music can really be attributed to the tonality without reservation. This is certainly true for many of the elements appearing there, and certainly not for many others. So Scarlatti has become a problem for music theory, which however rightly bears its name as long as practice proves its ineptitude.
With regard to the exceptions mentioned, I will limit myself to a few striking examples in this context. All of these examples are unusual and often unique in the history of tonality, as long as one wants to limit oneself to classifying this music as purely tonal. Here a unique opportunity has not been recognized by all know-it-alls. It concerns the chance of the symbiosis between modal and tonal music, which Scarlatti (the only one) has realized. The importance of this conclusion cannot be overestimated. Although music theory and publishers are unable to do anything sensible with it, it is precisely at this point that Scarlatti's uniqueness lies. Official music theory prefers not to concern itself with Scarlatti at all, and the appreciation he received from his contemporaries Handel and Bach is hushed up. So far so good. As far as the publishers are concerned, I will come back briefly to the edition of selected sonatas from Edition Schott. All sonatas in which elements appear that cannot be unequivocally assigned to the tonality have been eliminated - almost to punish Scarlatti for her own ignorance. It has to be mentioned, unfortunately you can't avoid it, people ask about it and after all it is a market, but its really extraordinary achievements should not be mentioned!
Unfortunately, it is the case that the tonality babblers, who are characterized by the fact that they understand absolutely nothing about the tonality, do not dare to venture into the uncertain area of modality and certainly do not get involved. To this day it is incomprehensible that current music theory does not know how to help itself other than to be able to examine phenomena of music, which are located both before and after the tonality, only through the tonality glasses or, better, vice versa: that they can look through the tonality magnifying glass under their glasses, which is probably the more likely solution to the riddle.
After these inevitable things are settled once and for all, we return to Scarlatti and henceforth keep him free from the odor of theorists and certain publishers.
1. The tonality of the half-close
There are major sonatas whose semi-finals end on the dominant, but in a minor key. As examples of several I will mention K518 and K545. The idea behind this way of dealing with modulations, which also applies to the major sonatas, both of which end in minor, has already been explained in the chapter on form. It concerns sonatas with two opposing main motifs, which in these cases consist of major and minor. If applied consistently, no other result is possible than with Scarlatti. And he was consistent. This is perhaps even clearer with the type of major sonatas, both parts of which end in minor. An excellent example is K107.
2. Major - minor
The first type to be discussed here are two-part major sonatas, both blocks of which end in minor. The aforementioned K107 not only sets major and minor against each other, but also tonality and modality, the latter being inspired by flamenco. Scarlatti's consistent musical thinking made him start both blocks in major and end in minor. This concerns a procedure that is very rare in the history of tonality. After Scarlatti, only Chopin used a similar procedure in his second ballad. Unfortunately, it is unknown whether Chopin knew Scarlatti's music.
The reverse type occurs a few times: sonatas in minor that end in major blocks (e.g. K174 or K519).
There is also a four-part type A - B - A - B, as already explained in the chapter on the form of the sonatas, whereby e.g. the A parts are in minor and the B parts are in major (K176). To further distinguish one from the other, the A parts are slow and the B parts are fast.
3. Sudden unprepared change of key
One of the surprising elements in Scarlatti's music are sudden, unprepared key changes to very remote keys. Often these take place after the halfway point, e.g. in K488 in B flat major. The half-ending ends in F major, i.e. the dominant. The second part begins in D flat major. The note f, the root note of the half-ending, is transformed to the third of D flat major.
This wealth of form and harmonic structure, briefly touched on here, is absolutely unique in the music history of the Baroque period. In addition to "normal" structures, there are also structures that cannot be denied because they are there. And yet these are ignored. In the chapters on the four creative periods, this matter is discussed in more detail.