Over the origin of this word there are different versions. Against the assumption, the term arose already in the 30's in Berlin, is considered in the meantime as very probable that the designation developed around 1948 in a conference of editorship of the northwestGerman broadcast (NWDR). The word creation is attributed Harry Hermann, actually Harry Hermann pointed (1899-1961), to the director/conductor at that time of the music department and boss of the maintenance orchestra of this transmitter.
However also similarly sounding words can be with responsible as the down-German snulten, which as much as sensitively talk meant, or also the rather colloquial adjective schnulle (= dear, nicely, sweetly) for the emergence of the expression. (Source:Duden 7)
With a sentimental song equal which category always Sentimentalität and agitating blessedness are connected. The ironically meant increase form is noble sentimental song. The adjective is called schnulzig.