Here is a little bit more on what Kirtan is, by GauraVani another kirtan artist:

In a simple word, Kirtan is relief. It has been described as the beating of the heart of the soul. For the twenty-first century person living in the west, life is all about the pursuit of happiness. We are guaranteed life and liberty, but kirtan is the means and end toward achieving the happiness that people are searching for. Through the chanting of the names of God, kirtan awakens the soul to its natural position, connects with God, clears the heart of all the distractions that can stress one living in this high tech age, and at the very least, make a person feel better about their day through the wonderful music.

Shri krishna govinda hare murari / Hey nath narayan vasudeva 

(All the names of god), I pay tribute to, love and honor thee.

recording of Bhagavan Das’ version