Almost none of the popular Jewish music originated with Jewish composers. Only the lyrics were changed. (Naturally.) For example, the popular song “Yidd’n” sang by MBD is taken from a German Rock band. (I don’t think it’s the other way around.) Even some of the Marches that are sung on Rosh Hahsana and Yom Kippur are adapted from music by (Old) Russian Composers. As some of the other posters have suggested, that the important thing is how it touches the soul.
