From super-soft to blowing-out-the-speakers volume, musicians rely on dynamics to denote the loudness and softness of the music they play. These notations on sheet music are relative terms, telling musicians how much louder or softer notes should be compared to how they were played throughout the previous part of the piece, or at what volume the piece should begin. One of the first documented use of these notations was in 1615, in posthumously published works of Giovanni Gabrieli.
Keeping on the Down Low
From the simple "p" for "piano" to the spelling-bee champion's challenge of "pppppp" for "pianissississississimo," softness in music is denoted by iterations of the letter "p." "piano," or "p," is soft; "pianissimo," or "pp," is softer; "pianississimo," or "ppp," is very soft; "pianissississimo," or "pppp," is very, very soft; "pianississississimo," or "pppp," is extremely soft; and "pppppp" is as soft as possible. Granted, most composers stick with just a few of the letters, but examples of the extremes include Tchaikovsky using "pppppp" for a bassoon -- or bass clarinet -- solo in "Pathetique Symphony" and Carl Nielsen using "ppppp" for woodwinds in the second movement of his Symphony No. 5.
Blasting It Out
On the opposite end of the volume spectrum is the "f" notations. It starts with "f" for "forte," or loud, and goes to "ffff" for "fortissississimo," or as loud as possible. There are examples of composers who have used greater numbers of "f" but even Holstz' "The Planets" only uses "ffff" -- twice in "Mars" and once in "Uranus."
All Things in Moderation
In between the f and the p, both alphabetically and musically, is "m." Moderately soft is marked by "mp," or "mezzo piano," and moderately loud is marked by "mf," or "mezzo forte." Because all dynamics are relative, what "mezzo" really means is that it is louder than piano but softer than forte. Mezzo forte is louder than mezzo piano.
Hitting It Hard
Loudness and softness also are denoted through the use of accented notes that require sudden changes or combine two dynamics. The terms "forzando" or "forzato" are marked by "fz" or "ffz" and instruct the musician to begin the note loudly with a very strong accent. "Sforzando" is marked by "sf," "sff" or "sfff" and denotes a sudden change to loud and accented. "Sforzato" is marked by "sfz," "sffz" or "sfffz" and indicates a note should be played loud and accented with legato -- which means without breaks and played smoothly. Composers also combine dynamics to get emotional effects. Fortepiano and pianoforte requires musicians to play first one then the other immediately afterward.
Turning the Volume Knob
Sometimes composers want musicians to gradually change the dynamics by getting louder or softer as they play through a phrase. To get this effect, they use crescendos or diminuendos/decrescendos. These are denoted with symbols under the phrase. A crescendo looks like "<" and is as long or short as the phrase the composer wants to gradually become louder. The longer it is, the slower the increase in volume. There often is a dynamic marking at the beginning and end, such as "mp