The Sostenuto

There are some extremely unclear, divergent views on the meaning of this term. To avoid misinterpretations, it is certainly appropriate to give a clear explanation of the meaning of this performance direction, which is not exhaustively treated even in Riemann’s otherwise excellent lexicon.^[1]

There seems to be agreement in the interpretation of the sostenuto when we find it placed before a movement as a tempo indication; e.g., Andante sostenuto or In tempo sostenuto, or simply Sostenuto.

However, differences opinion on the meaning immediately arise when the word in question appears in the course of a piece in an adjectival sense, such as accelerando, ritenuto, animato, stringendo, etc. We often find directions like this in the works of Brahms. In this case, the term means to play with restraint, in a well-balanced manner, and not carelessly. However, it is by no means equivalent to ritenuto or rallentando, which (as is well known) express a gradual and increasing slowing-down.

Thus, just as animato differs from accelerando (in that the former means an animation but not, like the latter, a continued acceleration), so sostenuto differs from ritenuto or rallentando. In this book, the designation sostenuto should be understood in this sense.