'Directors' in the Bible

For long ago, in the days of David and Asaph, there had been directors for the singers and for the songs of praise and thanks to God.

And I have not hearkened to the voice of my directors, And to my teachers have not inclined mine ear.

And the Lord hath given to you bread of adversity, And water of oppression. And thy directors remove no more, And thine eyes have seen thy directors,