One final thought about music and worship comes courtesy of John Piper:
We must make it our aim that the joy awakened by music be joy in God. Not all pleasures of music are pleasures in God. Then the effort to delight in God through music will involve a prior shaping of the mind by the Word, so that structures of sound that do not conform to God’s character are not pleasing in the first place. Then the effort to delight in God through music will also involve a thoughtful testing after the music has already awakened joy. Is this joy, we ask, rooted in something good about God? Is it shaping my emotions into a Christ-exalting configuration? Is it stirring my desires to know Christ better and love him more and show him to others at the cost of my own comfort? So before and after music has its immediate effect, we pursue the goal that music make us more glad in the glory of God. [When I Don’t Desire God]
Words of Grace 