We may read again from the excellent rules of Robert Schumann: 

“Frequently sing in choruses, especially the middle parts; this will help to make you musical.”

Out of this we learn to try to hear more than the melody, to try sometimes not to think of the melody, but to listen only to that which accompanies it.  When, in school, you sing in two and three parts, notice how one is inclined always to sing the soprano.  The melody pulls us away from another part if we are not concentrated upon our part.  Yet notice how beautifully musical the lower parts are.  Listen intently to them whatever part you sing.

It seems in music that we learn to listen in two directions.  First, by training the attention merely to follow prominent sounds and to be conscious of all of them; then, later, we do not need to think so much of the prominent melody but we strive to hear the accompanying parts.  These are the melodies which are somewhat concealed by the principal one; not truly concealed either, for they are plain enough if we will listen.  They make one think of flowers hidden in the grass and foliage.  They are none the less beautiful though they are concealed; for the sunlight seeks them out and makes them blossom.

We find hidden melodies in all good music because it is the character of good music to have interesting and beautiful melodic thought everywhere.  There are never meaningless tones allowed.  Every sound says something and is needed.  It is curious that in our playing the moment we put our thoughts upon any tone or voice part with the desire to hear it, it comes out at once as plainly as if it was the highest melody.  That illustrates the power of thought concentrated upon even a hidden thing.  You know how in Bach even the piano works move as if all parts were to be sung by voices.  It reminds one of conversation; of the story, of the question and answer, of the merry chat in a pleasant company.  Some bits of sentence are tripping and full of laughter,[17] others grave and majestic,[18] others have wonderful dignity of heart and mind.[19]

Such qualities give music interest and meaning in every part.  It will not take you long to discover that it is just the absence of these qualities that makes other music common.

The melody is not sustained by anything particularly well worth listening to.  One might say that good music is like the foliage of the garden, every leaf and petal variously yet finely formed, and all combined to make a beautiful whole.

When you have learned carefully to follow the accompaniment of a melody, try to follow the single voice parts in the chorus, particularly the Bass, Tenor, and Alto.  And when you go to orchestral concerts learn early to follow special instruments like the clarinet, the oboe, the drum.

Especially try to follow the lower strings, the viola, the ’cello, and the bass.  They are strongly characteristic.  You will learn their peculiar qualities only by giving them special and concentrated thought.  You will now see that acute and careful listening has its definite ways and purposes.  Here they are: