The primary audience for John Mayer would be males and females from the age of 15-24 years old as his songs have relevance to emotions and feelings that teens may have. The light element of some of his music would also appeal to a younger fanbase (especially girls).
The secondary audience would consist of people from the age of 25-34+ as some of his electric music would appeal as well to an older audience. Since his electric music is mostly blues based, it has a heavy and complicated element to it and would therefore easily appeal to an older and more mature audience. (Not to say that his light acoustic songs are immature as this is just a generalisation)
Since his music varies and ranges from acoustic folk, pop and electric blues, he is able to have quite a diverse audience which also enables him to have a wider fanbase, thus allowing him to have more revenue for his music.
