Dunedin Consort - Mozart: Requiem - musica Dei donum

Mozart's Requiem in d minor is one of the most frequently-performed compositions in music history. It is also the subject of much debate and research as the composer left it unfinished when he died in December 1791. Setting aside the myths which have been woven around this work and the reasons Mozart wrote it, it is especially the way his pupil Süßmayr finished the score which has been a matter of debate. Most scholars and interpreters feel that his contributions are rather below the standard of Mozart's own work, and several attempts have been made to create alternatives for the parts Mozart did not compose himself. Some 'reconstructions' are quite radical, others are more moderate, dependent on the view of Süßmayr's work. One of the aspects about which scholars have different views is to what extent Süßmayr's completion is based on material from Mozart's pen. 

There has been a time that many performances were based on one of these reconstructions, for instance by Franz Beyer, Richard Maunder or Robert Levin. However, I have the impression that today most performers seem to return to Süßmayr. After all, the reconstructions are all from our time, and Süßmayr is probably as close to Mozart as we can get. From a historical perspective the recordings by John Butt and Stephen Cleobury are particularly interesting. Both perform the Requiem in the edition by Süßmayr. Butt attempts to reconstruct the first performance in 1793, after Süßmayr had added the missing parts. His performance is based on a new edition of his version by David Ian Black who removed some later 'improvements'. Even more interesting is the line-up of this performance. 

The performance in 1793 was part of a benefit concert for Mozart's widow, Constanze, which was organized by his long-time patron, Baron Gottfied van Swieten. The performance was given by the Gesellschaft der Associierten Cavaliere, which in previous years had also been responsible for the performances of Mozart's arrangements of vocal works by Handel. Therefore Butt assumes that the forces with which they performed the Requiem were about the same as those in these Handel arrangements. He opted for a choir of sixteen voices, four of which sing the solo parts. This results in a strong coherence between soli and tutti. Butt states that this kind of line-up was common practice in the 17th and 18th centuries. Setting aside the number of singers involved it is certainly true that sacred music was usually not scored for soloists, choir and orchestra, but rather for a vocal and instrumental ensemble. There is not only a unity between soli and tutti, but also between the soloists. That comes especially to the fore in the 'Tuba mirum', but less so in the Benedictus, due to the slight vibrato of Rowan Hellier. There is also some vibrato now and then in the tutti, especially in the Kyrie. However, these are only minor blots on a generally very impressive performance which has certainly some dramatic traits, but - thanks to the relatively small forces - is rather intimate, which suits this piece quite well. Butt believes that there was probably no organ at the performance of 1793 and therefore makes use of a fortepiano. Unfortunately it is hardly audible. 

Butt also refers to a performance just five days after Mozart's death. It is not possible to know exactly which parts were performed, but certainly not the version by Süßmayr as he had not completed the missing parts yet. Butt performs only the Requiem aeternam and the Kyrie, in a line-up which is probably identical with that of the 1791 performance: four voices for the solo parts with four ripieno singers, single strings and lesser wind. From that time also dates Misericordias Domini (KV 222) which is performed here with the same forces. 
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John Butt is the only of the four conductors who opted for the German pornunciation of Latin. That seems historically correct, and I wonder whether any of the other coductors has given this subject any thought.