Your whole body is made up of atoms. Being with this truth kindles the energy in you and brings up consciousness. When you sing bhajans, the Sound Energy Vibration Gets Absorbed Into Every Particle Of Your Body.
Just like a microphone absorbs sound and converts it into electricity, the body absorbs the vibrations and converts them into consciousness.
When you sit in bhajans your entire body gets soaked in energy and transformation happens.
If you are sitting and listening to gossip or violent music, then that gets absorbed by your body and does not give a nice feeling.
When you hear the Knowledge, or chant with all your heart, that elevates your consciousness.
There is an ancient proverb in Sanskrit that says that the words of Rishis and Enlightened ones are translated into experience immediately!