Decrescendo

In music, the dynamics of a piece is the variation in loudness between notes or phrases. Dynamics are indicated by specific musical notation, often in some detail. However, dynamics markings still require interpretation by the performer depending on the musical context: for instance a piano (quiet) marking in one part of a piece might have quite different objective loudness in another piece, or even a different section of the same piece. The execution of dynamics also extends beyond loudness to include changes in timbre and sometimes tempo rubato.

The two basic dynamic indications in music are:

More subtle degrees of loudness or softness are indicated by:

Use of up to three consecutive fs or ps is also common:

The overall ranking of these is:

A less common dynamic marking used especially by Johannes Brahms is:

While the typical range of dynamic markings is from ppp to fff, some pieces use additional markings of further emphasis. This kind of usage is most common in orchestral works from the late 19th-century onwards. Generally, these markings are supported by the orchestration of the work, with heavy forte markings brought to life by having many loud instruments like brass and percussion playing at once. For instance, in Holst's The Planets, ffff occurs twice in "Mars" and once in "Uranus", often punctuated by organ. It also appears in Heitor Villa-Lobos' Bachianas Brasileiras No. 4 (Prelude), and in Liszt's Fantasy and Fugue on the chorale "Ad nos, ad salutarem undam". The Norman Dello Joio Suite for Piano ends with a crescendo to a ffff, and Tchaikovsky indicated a bassoon solo pppppp (6 p) in his Pathétique Symphony and ffff in passages of his 1812 Overture and the 2nd movement of his Fifth Symphony.

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