Klaus Hallen is probably best known for his tribute CDs, where the music of a popular artist like Barbra Striesand or Frank Sinatra is featured on a CD. Unlike some dance CDs which use the version by the original artist Klaus Hallen's orchestra plays the piece of music in strict-time accompanied by the vocals of an impersonator. The quality of the vocals is not only excellent but often surprising, in it's ability to so closely match the original artist.