Include a cappella music in your ear training and you’ll become more sensitive to pitch, harmony and timbre. Why?
The power of the voice
The human hearing system has naturally developed over thousands of years to be particularly attuned to the human voice. Speaking, shouting or singing, the human voice has a powerful effect on us in a way that no other instrument can manage.
This means that music consisting solely of human voices tends to engage our ears in a particularly effective way. As you practice active listening you may find it easier to pay careful attention when the music in question is a cappella.