Head (music) - What's in A Head

What's in A Head

The idea a head represents comprises a combination of elements. No one piece of written music defines what the "head" of many jazz tunes really is, but a boiler-plate jazz chart, which is often only a page long in large print, will tell you

• a key and time signature
• a melody
• a set of chord changes (referred to simply as "the changes")
• sometimes, but rarely, lyrics

as well as more general information such as

• the title and author of the piece
• indications of style, tempo, dynamics and form.

The form is an even more general and abstract concept dealing with the theoretical context in which the actual music is being played: the chord progression, its sections and other miscellaneous events such as kicks or time changes are all important information that the musician, or musicians, must keep track of and usually repeat many times (commonly eight to fifteen or more). The "form" does not include the melody to the piece, and as such there is a difference between knowing the head and merely knowing the form. Two important standard forms over which hundreds of heads have been written are the 12-bar blues and rhythm changes. There are also heads written based on the forms of other tunes, such as Charlie Parker's Ornithology, based on Morgan Lewis's chord changes in How High the Moon. So often on the bandstand at a jam session, though it is frowned upon, musicians can get away with knowing the form if they don't know the head.

Many fake books, some of which are considered standard literature among jazz musicians, exist containing anywhere from a handful to hundreds of charts like these, occasionally stretching into two pages and on rare occasions going further and requiring page turns. A song can be played in any number of ways from the head on any one of these charts for any length of time; all the music contains is enough information for the musician to understand the head (and extrapolate from it).

There are many, many heads which are considered part of standard jazz repertoire, and professional players are expected to know these tunes by memory and be able to perform them in a variety of ways on the spot. In this regard, the information associated with a head can be very wide-ranging and the information presented on the chart is really only the tip of the iceberg. Invoking the name of Sonnymoon for Two is invoking a history of performances, arrangements, tricks and variations upon what is really only (in this instance) a four-bar phrase, all of which constitute knowledge about what is ultimately called the head.