Most covers stay pretty true to the original song. It’s easy to recognize them as covers just by listening.
Some covers, though, are completely unrecognizable from their original songs, like Julia Stone’s cover of “You’re The One That I Want” from Grease and 67 Special’s cover of “Scar” by Missy Higgins:
“You’re The One That I Want”:
“Scar”:
But sometimes figuring out what qualifies as a cover can be harder. What about when a singer plays his song with a different band? Is it simply the same song and not a cover, or is it a totally new composition, or a semi-cover?
Two good examples of this murky cover definition are when Jenny Lewis played a song from her solo album with Rilo Kiley. The vocals were the same, but the music was different, and when Nina from Girl in a Coma played her song “Smart” with Joseph from Deadbeat Darling, turning the song into a duet:
“Rise Up With Fists”:
“Smart”:
There’s a fine line — An artist should make a cover her own, injecting her own fingerprint onto it, but if a cover is so drastically different from the original that it loses/ignores the melody, that’s not satisfying for the listener.