At a concert, a hip audience is known as a 2 and 4 crowd (as opposed to a 1 and 3 crowd). It refers to the beat that the crowd is likely to clap along to.
Bob: "Man great audience tonight, we were rockin'"
Mick: "Yeah man, they were definitely a 2 and 4 crowd!"
Mick: "Yeah man, they were definitely a 2 and 4 crowd!"
by toroboy January 30, 2010