Octaves – Playing By Ear Chord 1 2 In this lesson, you will hear an octave played as a chord, then play it by ear on your instrument. Octaves can be challenging to hear because when both notes are played together they sound almost alike. Please press the Exercise button below. May 16, 2013 1 2 In this lesson, you will hear an octave played as a chord, then play it by ear on your instrument. Octaves can be challenging to hear because when both notes are played together they sound almost alike. Please press the Exercise button below.