Crooner is an American epithet given to male singers of jazz standards, mostly from the Great American Songbook, either backed by a full orchestra, a big band or by a piano. Originally it was an ironic term denoting a sentimental singing style made possible by the use of microphones. Some performers, such as Russ Columbo, did not accept the term: Frank Sinatra once said that he did not consider himself or Bing Crosby "crooners".