A frequent concept in the lay history of popular music, as it exists, is the idea of going mainstream. A musical genre is dislodged from its original community (a subculture or a high-culture setting) and enters a broad, generally well-known and generally well-liked central stream in the world of information, being frequently featured in all media. It reaches the lower-middle class and probably the working class, and in the process gets looked down upon and becomes uninteresting for the participants in the original subculture.
This certainly happens, and happens reasonably frequently. But it's perfectly possible, though significantly rarer, for the opposite to happen - for a broadly working-class, declassé genre to become a hip cultural expression for the clever, upper-middle-class subculture, what Swedish magazine ODD at Large called the "sharp culture".
Think of it as a process of musical gentrification. Without passing through a middle-class, "mainstream" phase first (like happened with rock'n'roll), a contemporary working-class music becomes the musical expression of choice for a cultural elite. It is made possible entirely by separation - the lower middle-class shuns the musical products of the working class but the elite who never encounters them can well embrace it.
Nevertheless it is rare. Let's exclude "the tradition in Britain [...] of being interested in declining forms of Negro popular music" (Gillett) and other purist folkie roots-seeking, focussing only on contemporary moves. Let's also skip all the music stuck in the initial stages of (a) people being interested in the music and (b) people being the interpreters and distributors of the music and focus on the music that's actually become the music created by the sharp elite. Only a contemporary sublimation where the music goes from being created by the working class to being created by an elite.
I can only think of a small number of examples. Alt. country is a textbook one - a small, artistically inclined elite picks up totally contemporary working-class music and adapts its imagery, musical themes and methods of creation. Eurodisco, for a brief period before going completely mainstream, is a straightforward adaptation of contemporary African-American music by a european elite, admittedly via a New York one which, at the time, didn't create music itself. Currently, in Brazil, the highly elite "Não Funk" crowd with bands like Bonde Do Role and Edu K are busy taking the music of the favelas to the upper-middle-class suburbs.
And then there's the global ghettotech of Ghislain Poirier and MIA. I guess that's a fairly good example as well, despite (or perhaps because?) of the great distance between the artists who have inspired and the artists who have taken it up.
I really wish I had a good reason to dislike this kind of music, because I mostly prefer the original stuff that inspires it, but I struggle to think of one. Unlike the "adaptation of declining styles" it doesn't necessarily slow down progress; in fact it can be highly innovative. Nor does it, being so narrow and all, usually have a major impact on the original scene, thus not destroying anything and just adding new music to the spectrum. Being artists themselves, the musicians act considerably less like interpreters/potential warpers, and only stand for their own music.
Nevertheless, I can see two potential effects that can be seen as negative. Firstly, it is quite possible as the disco example illustrates that the musical gentrification is only a stage towards the genre going mainstream. I'm not sure this is always a bad thing, but still. Secondly, it's perfectly possible for the "new" genre to totally block out the original's resources and media space, the new artists having the verbal ability and the participatory voice necessary to reach out better.
What do you think? Is "gentrified music" a good thing or a bad thing, and why?