I don't consider myself a pianist (and neither does anyone who's heard me play), - but I do spend a fair amount of time at the piano working on my compositions, improvising themes, variations, counter melodies and chord progressions. Much of what I like is influenced by jazz musicians of the 60's, 70's and 80's, so improvising seems to be a natural extension of this style of music.
My wife, Eddie Louise, grew up listening to Country music, and so her own particular style is influenced with more of a traditional folk feel. If you listen to our classical compositions you definitely get a sense of folk influences on Eddie's music, while mine tend toward jazz influences (as you might expect). Both of us also are influenced by classical music, Eddie tends to enjoy Mozart and Debussy as I veer toward Shostakovich.
Our mutual love of Aaron Copland is one place where our classical sides mesh. His folk/Americana stylings appeal to my wife, for myself (like the jazz music I listened to,) Copland was a composer I enjoyed in my youth and so the music became an interest all on its own. Or maybe it's the bold style of his "Fanfare for a Common Man" (performed by practically every high school band in the US and where I first played it) that is in many respects like Shostakovich's 5th and 7th Symphonies that resonates with me. The fact remains, while Copland created the Americana sound - he used an American folk hymn in "Appalachian Spring" - no one considers his music folk music, but rather folk influenced. On the other hand, when Copland attempted to wed Jazz and classical, the results were viewed unevenly and with suspicion by both the critics and the composer himself.
When studying Bela Bartók, I spent a fair amount of time learning about his use of folk themes in compositions. Numerous composers have done similar things, Mozart, Beethoven, Brahms, Dvořák... the list goes on. Many modern composers have followed suit, yet I find it interesting that the accepted references hearken back to folk music with rural elements. Bartók was utilizing themes from small villages, music that was integral to the small social groups of the more remote regions, created for the purpose of social interaction. He did this in an effort to preserve these themes, and in some way immortalize them. Is the rural nature of the music what makes it acceptable to use in classical composition?
To better examine this question we start with the definition of folk music:
folk music – noun
1. music, usually of simple character and anonymous authorship, handed down among the common people by oral tradition. 2. music by known composers that has become part of the folk tradition of a country or region.
By that definition, isn't jazz a form of folk music, music that has become part of a country or a region? Jazz is certainly considered an American music creation even though there are jazz artists around the world now. Perhaps then the same can be said of Rock, which certainly has its roots in both jazz and country music (and country music, at least the country music of say 60 or 70 years ago) is certainly folk music. Blue Grass is definitely folk music (American roots music) and yet, isn't it also a form of jazz? Ragtime and Dixieland are both forms of jazz and also folk music.
Another mutual love for my wife and I is the music of George Gershwin. He was a master of melodies, which my wife adores and also steeped in jazz which really gets my foot tapping. His music was very popular during our formative years and was often performed in concerts, used as advert music and themes for television shows, shown on the Saturday afternoon films and his musicals were regularly performed.
Perhaps the most popular jazz influenced classical piece is George Gershwin's ""Rhapsody in Blue", (IMHO) a great piece of music. It is influenced by ragtime music as well as Cuban clave rhythms (which are also the backbone of 1920's dance craze The Charleston). Because "Rhapsody in Blue" is completely composed it has moved away from the true jazz form (which typically has elements of improvisation), but the style of the music is definitely jazz influenced. Paul Whiteman, who asked George Gershwin to write a "jazz concerto", was hoping to expand the definition of classical music, and to make classical music more accessible to the general public.
Analyzing "Rhapsody in Blue" shows the piece is not a simple ii, V, I chord progression, but utilizes a number of classical concepts and takes others (like moving the opposite direction around the circle of fifths) and turns them about. It has numerous dance like themes and yet, it isn't a dance piece - the tempo shifts too often to be good dance music. Analysts argue whether this is a classical piece with jazz influence, or a jazz piece with elements of classical styling. Leonard Bernstein said it's "not a composition at all [but] a string of … terrific tunes … stuck together with a thin paste of flour and water."
What "Rhapsody in Blue" did do is encourage other composers like Ravel, Stravinsky and Milhaud to explore jazz influence in classical music. So, is jazz a form of folk music? By extension, is the inclusion of jazz elements in a composition the use of folk idioms? Gershwin's music is very popular in the US so does that mean it is folk influenced, or does the popularity of his music make it folk music of its own right? I struggle with the concept of what is folk music and thereby what it means to write folk influenced classical music. When is it acceptable to use "folk" references in classical music compositions, and why does the use of other forms of music styles not have the same acceptability?
Edgar Meyer wrote a Violin Concerto for Hilary Hahn which incorporates folk elements in the composition. The music is lovely and definitely classical music, with a sense of the folk or Americana (the sound attributed to Copland and the use of American folk idioms). My own violin concerto is influenced by jazz, but not the jazz of Gershwin's era (Louis Armstrong, Jellyroll Morton and Bix Biederbecke) but of the composers I listened to in my youth - Dave Brubeck, Chic Corea, Chuck Mangione, Doc Severinsen, Grover Washington Jr., Thelonious Monk. These were performers/composers who were writing music that was for me very much folk, a music of the people, influenced or created out of a sense of social interaction.
The 1st and 3rd movements of my concerto have a fair number of jazz chords/progressions and rhythms that give them a feeling of being something out of the Brubeck/Corea era of jazz. Even so, some of the rhythmic elements go beyond, and some of the harmonies in the 2nd movement are influenced by Witold Lutosławski and cluster chords.
My violin concerto is completely composed, so the "solo" sections (or cadenzas) are not improvised but "scripted". Like Gershwin's "Rhapsody in Blue", my violin concerto then falls out of the realm of jazz and into the classical. But why does writing it out make it classical, or improvising make it non-classical? Mozart did not write out the cadenzas in his concertos. Is this because he expected the players to improvise? Does that mean Mozart's concertos were more like jazz pieces where the theme is played, then the soloist takes over???
Certainly Bach's music is written, but we know Bach's ability to improvise at the keyboard eas crucial to how much of his music was written. Beethoven and Liszt often gave performances of improvised works along with their written compositions. So, is improvising a classical or non-classical art form?
I suppose the attempt to label things is part of the problem. The moment a label is created - a definition as to what constitutes something - there is always something that steps outside the definition and becomes something new. Gershwin's "Rhapsody in Blue" was definitely something new. I hope my violin concerto has the same effect, creating a new sense of what's possible on the violin while incorporating modern jazz elements into a classically written piece.