Job 21:12

They take the timbrel and harp
Not the children, but the parents of them; these took these instruments of music into their hands, and played upon them while their children danced; thus merrily they spent their time: or, as Jarchi and Aben Ezra, they lift up the voice with the tabret and harp; that is, while they played on these with their hands, they sung songs with their mouths; they used both vocal and instrumental music together, to make the greater harmony, and give the greater pleasure, like those in ( Amos 6:5 Amos 6:6 ) ;

and rejoice at the sound of the organ;
a musical instrument, very pleasant and entertaining, from whence it has its name in the Hebrew tongue; but of what form it was cannot be with certainty said; that which we now so call is of later invention, and unknown in those times: probably Job may have respect to Jubal, the inventor of this sort of music, and others of the posterity of Cain before the flood, who practised it, and were delighted in it; in which they were imitated and followed by wicked men after it, and in Job's time, ( Genesis 4:21 ) .