Home Free Covers Johnny Cash’s ‘Ring of Fire’ a Capella With Pentatonix’s Avi Kaplan [Video]Home Free Covers Johnny Cash’s ‘Ring of Fire’ a Capella With Pentatonix’s Avi Kaplan [Video]Fans of a cappella group Home Free will be super psyched about their latest cover video: Johnny Cash's 'Ring of Fire,' featuring Pentatonix's Avi Kaplan.Michelle McGahanMichelle McGahan