One of the most important skills you can learn with ear training is how to find the tonic of a given song or composition. This gives you information about how the music is organized, and tells you what chords it is likely rooted in. Also, if you get lost in a song and can’t understand what’s going on musically, using the tonic as a point of reference can help get you back on track!
Finding the tonic in sheet music is a fairly straightforward process; you have all the notes written out for you, and a key signature to help you out even further. But what if you don’t have sheet music? What about finding the tonic by ear?