Minor 3rds Playing by Ear 1 2 Now we will learn to play Minor 3rds by ear on your instrument. By itself, a minor 3rd typically has a somewhat sad sound.November 26, 2012 1 2 Now we will learn to play Minor 3rds by ear on your instrument. By itself, a minor 3rd typically has a somewhat sad sound. Minor 3rd – Up Brahms Lullaby Please press the exercise button below.